Search

PURPOSE Despite extensive randomized evidence supporting the use of treatment breaks in metastatic colorectal cancer (mCRC), they are not universally offered to patients despite improvements in quality of life without detriment to overall survival (OS). FOCUS4-N was set up to explore the impact of oral maintenance therapy in patients who are responding to first-line therapy. METHODS FOCUS4 was a molecularly stratified trial program that registered patients with newly diagnosed mCRC. The FOCUS4-N trial was offered to patients in whom a targeted subtrial was unavailable or biomarker tests failed. Patients were randomly assigned using a 1:1 ratio between maintenance capecitabine and active monitoring (AM). The primary outcome was progression-free survival (PFS) with secondary outcomes including OS toxicity and tolerability. RESULTS Between March 2014 and March 2020, 254 patients were randomly assigned (127 to capecitabine and 127 to AM) across 88 UK sites. Baseline characteristics were balanced. There was strong evidence of efficacy for PFS (hazard ratio = 0.40; 95% CI, 0.21 to 0.75; P < .0001), but no significant improvement in OS (hazard ratio, 0.93; 95% CI, 0.69 to 1.27; P = .66) was observed. Compliance with treatment was good, and toxicity from capecitabine versus AM was as expected with grade ≥ 2 fatigue (25% v 12%), diarrhea (23% v 13%), and hand-foot syndrome (26% v 3%). Quality of life showed little difference between the groups. CONCLUSION Despite strong evidence of disease control with maintenance therapy, OS remains unaffected and FOCUS4-N provides additional evidence to support the use of treatment breaks as safe management alternatives for patients who are stable or responding to first-line treatment for mCRC. Capecitabine without bevacizumab may be used to extend PFS in the interval after 16 weeks of first-line therapy.

BACKGROUND: Primary tumour location (PTL) is being adopted by clinicians to guide treatment decisions in metastatic colorectal cancer (mCRC). Here we test PTL as a predictive marker for panitumumab efficacy, and examine its relationship with an extended biomarker profile. We also examine rectal tumours as a separate location. PATIENTS AND METHODS: mCRC patients from the second-line PICCOLO trial of irinotecan versus irinotecan/panitumumab (IrPan). PTL was classified as right-PTL, left-PTL or rectal-PTL. PTL was assessed as a predictive biomarker for IrPan effect in RAS-wild-type (RAS-wt) patients (compared with irinotecan alone), then tested for independence alongside an extended biomarker profile (BRAF, epiregulin/amphiregulin (EREG/AREG) and HER3 mRNA expression). RESULTS: PTL data were available for 1180 patients (98.5%), of whom 558 were RAS-wt. High HER3 expression was independently predictive of panitumumab overall survival improvement, but PTL and EREG/AREG were not. IrPan progression-free survival (PFS) improvement compared with irinotecan was seen in left-PTL [hazard ratio (HR) = 0.61, P = 0.002) but not right-PTL (HR = 0.98, P = 0.90) (interaction P = 0.05; RAS/BRAF-wt interaction P = 0.10), or in rectal-PTL (HR = 0.82, P = 0.20) (interaction P = 0.14 compared with left-PTL; RAS/BRAF-wt interaction P = 0.04). Patients with right-PTL and high EREG/AREG or HER3 expression, had IrPan PFS improvement (high EREG/AREG HR = 0.20, P = 0.04; high HER3 HR = 0.33, P = 0.10) compared with irinotecan. Similar effect was seen for rectal-PTL patients (high EREG/AREG HR = 0.44, P = 0.03; high HER3 HR = 0.34, P = 0.05). CONCLUSIONS: RAS-wt patients with left-PTL are more likely to have panitumumab PFS advantage than those with right-PTL or rectal-PTL. However, an extended biomarker panel demonstrated significant heterogeneity in panitumumab PFS effect within a tumour location. AREG/EREG and HER3 mRNA expression identifies patients with right-PTL or rectal-PTL who achieve similar PFS effect with panitumumab as left-colon patients. Testing could provide a more reliable basis for clinical decision making. Further validation and development of these biomarkers is required to optimise routine patient care. CLINICAL TRIAL REGISTRATION: ISRCTN identifier: ISRCTN93248876. ispartof: ANNALS OF ONCOLOGY vol:31 issue:8 pages:1021-1029 ispartof: location:England status: published

Background Patient selection for addition of anti-EGFR therapy to chemotherapy for patients with RAS and BRAF wildtype metastatic colorectal cancer can still be optimised. Here we investigate the effect of anti-EGFR therapy on survival in different consensus molecular subtypes (CMSs) and stratified by primary tumour location. Methods Retrospective analyses, using the immunohistochemistry-based CMS classifier, were performed in the COIN (first-line oxaliplatin backbone with or without cetuximab) and PICCOLO trial (second-line irinotecan with or without panitumumab). Tumour tissue was available for 323 patients (20%) and 349 (41%), respectively. Results When using an irinotecan backbone, anti-EGFR therapy is effective in both CMS2/3 and CMS4 in left-sided primary tumours (progression-free survival (PFS): HR 0.44, 95% CI 0.26–0.75, P = 0.003 and HR 0.12, 95% CI 0.04–0.36, P P = 0.02). Efficacy using an oxaliplatin backbone was restricted to left-sided CMS2/3 tumours (HR 0.57, 95% CI 0.36–0.96, P = 0.034). Conclusions The subtype-specific efficacy of anti-EGFR therapy is dependent on the chemotherapy backbone. This may provide the possibility of subtype-specific treatment strategies for a more optimal use of anti-EGFR therapy.

Background Unplanned subgroup analyses from several studies have suggested primary tumor sidedness (PTS) as a potential prognostic and predictive parameter in metastatic colorectal cancer (mCRC). We aimed to investigate the impact of PTS on outcomes of mCRC patients. Methods PTS data of 9277 mCRC patients from 12 first-line randomized trials in the ARCAD database were pooled. Overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan-Meier and Cox models adjusting for age, sex, performance status, prior radiation/chemotherapy, and stratified by treatment arm. Predictive value was tested by interaction term between PTS and treatment (cetuximab plus chemotherapy vs chemotherapy alone). All statistical tests were 2-sided. Results Compared with right-sided metastatic colorectal cancer patients (n = 2421, 26.1%), left-sided metastatic colorectal cancer patients (n = 6856, 73.9%) had better OS (median = 21.6 vs 15.9 months; adjusted hazard ratio [HRadj] = 0.71, 95% confidence interval [CI] = 0.67 to 0.76; P < .001) and PFS (median = 8.6 vs 7.5 months; HRadj = 0.80, 95% CI = 0.75 to 0.84; P < .001). Interaction between PTS and KRAS mutation was statistically significant (Pinteraction < .001); left-sidedness was associated with better prognosis among KRAS wild-type (WT) (OS HRadj = 0.59, 95% CI = 0.53 to 0.66; PFS HRadj =0.68, 95% CI = 0.61 to 0.75) but not among KRAS mutated tumors. Among KRAS-WT tumors, survival benefit from anti-EGFR was confirmed for left-sidedness (OS HRadj = 0.85, 95% CI = 0.75 to 0.97; P = .01; PFS HRadj = 0.77, 95% CI = 0.67 to 0.88; P < .001) but not for right-sidedness. Conclusions The prognostic value of PTS is restricted to the KRAS-WT population. PTS is predictive of anti-EGFR efficacy, with a statistically significant improvement of survival for left-sidedness mCRC patients. These results suggest treatment choice in mCRC should be based on both PTS and KRAS status.

Impact of geography on prognostic outcomes of 21,509 patients with metastatic colorectal cancer enrolled in clinical trials: an ARCAD database analysis\ud Show less\ud Jun Yin*, Shaheenah Dawood*, Romain Cohen, Jeff Meyers, John Zalcberg, Takayuki Yoshino, Matthew Seymour, Tim Maughan, Leonard Saltz, Eric Van Cutsem, Alan Venook, Hans-Joachim Schmoll, Richard Goldberg, Paulo Hoff, J. Randolph Hecht, Herbert Hurwitz, Cornelis Punt, Eduard Diaz Rubio, Miriam Koopman, Chiara Cremolini, Volker Heinemann, Christophe Tournigard, Carsten Bokemeyer, Charles Fuchs, Niall Tebbutt, John Souglakos, Jean-Yves Doulliard, Fairooz Kabbinavar, Benoist Chibaudel, Aimery de Gramont, Qian Shi, Axel Grothey, Richard AdamsFirst Published June 30, 2021 Research Article\ud https://doi.org/10.1177/17588359211020547\ud Article information \ud Article has an altmetric score of 7 Open AccessCreative Commons Attribution, Non Commercial 4.0 License\ud Article Information\ud Volume: 13\ud Article first published online: June 30, 2021; Issue published: January 1, 2021\ud Received: December 29, 2020; Accepted: May 05, 2021\ud Jun Yin*\ud Department of Health Sciences Research, Mayo Clinic, 200 First Street, SW Rochester, MN 55905, USA\ud Shaheenah Dawood*\ud Mediclinic City Hospital: North Wing, Dubai Health Care City, Dubai UAE\ud Romain Cohen\ud Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA\ud Jeff Meyers\ud Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA\ud John Zalcberg\ud School of Public Health and Preventative Medicine, Monash University, Melbourne, Australia\ud Takayuki Yoshino\ud Department of Gastrointestinal Oncology, National Cancer Center Hospital East, Chiba, Japan\ud Matthew Seymour\ud NIHR Clinical Research Network, Leeds, UK\ud Tim Maughan\ud CRUK/MRC Oxford Institute for Radiation Oncology, Oxford, UK\ud Leonard Saltz\ud Memory Sloan Kettering Cancer Center, New York, NY, USA\ud Eric Van Cutsem\ud Digestive Oncology, University Hospitals Gasthuisberg Leuven and KU Leuven, Leuven, Belgium\ud Alan Venook\ud Department of Medicine, The University of California San Francisco, San Francisco, CA, USA\ud Hans-Joachim Schmoll\ud Klinik fur Innere Med IV, University Clinic Halle, Saale, Germany\ud Richard Goldberg\ud Department of Oncology, West Virginia University, Morgantown, WV, USA\ud Paulo Hoff\ud Centro de Oncologia de Brasilia do Sirio Libanes: Unidade Lago Sul, Siro Libanes, Brazil\ud J. Randolph Hecht\ud Ronald Reagan UCLA Medical Center, UCLS Medical Center, Santa Monica, CA, USA\ud Herbert Hurwitz\ud Duke Cancer Institute, Duke University, Durham, NC, USA\ud Cornelis Punt\ud Department of Medical Oncology, University of Amsterdam, Amsterdam, The Netherlands\ud Eduard Diaz Rubio\ud Department Oncology, Hospital Clínico San Carlos, Madrid, Spain\ud Miriam Koopman\ud Department of Medical Oncology, University Medical Center Utrecht, University of Utrecht, Utrecht, The Netherlands\ud Chiara Cremolini\ud Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy\ud Volker Heinemann\ud Department of Medical Oncology and Comprehensive Cancer Center, University of Munich, Munich, Germany\ud Christophe Tournigard\ud Hopital Henri Mondor, Creteil, France\ud Carsten Bokemeyer\ud Department of Oncology, Hematology and Bone Marrow Transplantation with Section of Pneumology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany\ud Charles Fuchs\ud Director of Yale Cancer Center, Boston, MA, USA\ud Niall Tebbutt\ud Sydney Medical School, University of Sydney, Sydney, Australia\ud John Souglakos\ud University of Crete, Heraklion, Greece\ud Jean-Yves Doulliard\ud University of Nantes Medical School, Nantes, France\ud Fairooz Kabbinavar\ud UCLA Medical Center, Santa Monica, CA, USA\ud Benoist Chibaudel\ud Department of Medical Oncology, Franco-British Institute, Levallois-Perret, France\ud Aimery de Gramont\ud Department of Medical Oncology, Franco-British Institute, Levallois-Perret, France\ud Qian Shi\ud Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA\ud Axel Grothey\ud West Cancer Center, Germantown, TN, USA\ud Richard Adams\ud Cardiff University and Velindre Cancer Center, Cardiff, UK\ud \ud Corresponding Author:\ud \ud yin.jun@mayo.edu\ud *Co-first authors.\ud \ud https://creativecommons.org/licenses/by-nc/4.0/This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access page (https://us.sagepub.com/en-us/nam/open-access-at-sage).\ud Abstract\ud Background:\ud Benchmarking international cancer survival differences is necessary to evaluate and improve healthcare systems. Our aim was to assess the potential regional differences in outcomes among patients with metastatic colorectal cancer (mCRC) participating in international randomized clinical trials (RCTs).\ud \ud Design:\ud Countries were grouped into 11 regions according to the World Health Organization and the EUROCARE model. Meta-analyses based on individual patient data were used to synthesize data across studies and regions and to conduct comparisons for outcomes in a two-stage random-effects model after adjusting for age, sex, performance status, and time period. We used mCRC patients enrolled in the first-line RCTs from the ARCAD database, which provided enrolling country information. There were 21,509 patients in 27 RCTs included across the 11 regions.\ud \ud Results:\ud Main outcomes were overall survival (OS) and progression-free survival (PFS). Compared with other regions, patients from the United Kingdom (UK) and Ireland were proportionaly over-represented, older, with higher performance status, more frequently male, and more commonly not treated with biological therapies. Cohorts from central Europe and the United States (USA) had significantly longer OS compared with those from UK and Ireland (p = 0.0034 and p

Background: Translating results from randomized trials to individual patients is challenging, since treatment effects may vary due to heterogeneous prognostic characteristics. We aimed to demonstrate model development for individualized treatment effect predictions in cancer patients. We used data from two randomized trials that investigated sequential versus combination chemotherapy in unresectable metastatic colorectal cancer (mCRC) patients. Material and methods: We used data from 803 patients included in CAIRO for prediction model development and internal validation, and data from 1423 patients included in FOCUS for external validation. A Weibull model with pre-specified patient and tumour characteristics was developed for a prediction of gain in median overall survival (OS) by upfront combination versus sequential chemotherapy. Decision curve analysis with net benefit was used. A nomogram was built using logistic regression for estimating the probability of receiving second-line treatment after the first-line monochemotherapy. Results: Median-predicted gain in OS for the combination versus sequential chemotherapy was 2.3 months (IQR: −1.1 to 3.7 months). A predicted gain in favour of sequential chemotherapy was found in 231 patients (29%) and a predicted gain of >3 months for combination chemotherapy in 294 patients (37%). Patients with benefit from sequential chemotherapy had metachronous metastatic disease and a left-sided primary tumour. Decision curve analyses showed improvement in a net benefit for treating all patients according to prediction-based treatment compared to treating all patients with combination chemotherapy. Multiple characteristics were identified as prognostic variables which identify patients at risk of never receiving second-line treatment if treated with initial monochemotherapy. External validation showed good calibration with moderate discrimination in both models (C-index 0.66 and 0.65, respectively). Conclusions: We successfully developed individualized prediction models including prognostic characteristics derived from randomized trials to estimate treatment effects in mCRC patients. In times where the heterogeneity of CRC becomes increasingly evident, such tools are an important step towards personalized treatment.

PURPOSE To compare cisplatin plus fluorouracil (FU) versus carboplatin plus paclitaxel in chemotherapy-naïve advanced anal cancer to establish the optimal regimen. PATIENTS AND METHODS Patients who had not received systemic therapy for advanced anal cancer were randomly assigned 1:1 to intravenous cisplatin 60 mg/m2 (day 1) plus FU 1,000 mg/m2 (days 1-4) every 21 days or carboplatin (area under the curve, 5; day 1) plus paclitaxel 80 mg/m2 (days 1, 8, and 15) every 28 days for 24 weeks, until disease progression, intolerable toxicity, or withdrawal of consent. Primary end point was objective response rate (ORR). Primary and secondary end points were assessed in a hierarchic model to compare the regimens and pick the winner. RESULTS We conducted an international multicenter randomized phase II study in 60 centers between December 2013 and November 2017. Median follow-up was 28.6 months. A total of 91 patients were randomly assigned: 46 to cisplatin plus FU and 45 to carboplatin plus paclitaxel. ORR was 57% (95% CI, 39.4% to 73.7%) for cisplatin plus FU versus 59% (95% CI, 42.1% to 74.4%) for carboplatin plus paclitaxel. More serious adverse events were noted in the cisplatin plus FU arm (62%) compared with the carboplatin plus paclitaxel arm (36%; P = .016). Median progression-free survival was 5.7 months (95% CI, 3.3 to 9.0 months) for cisplatin plus FU compared with 8.1 months (95% CI, 6.6 to 8.8 months) for carboplatin plus paclitaxel. Median overall survival was 12.3 months for cisplatin plus FU (95% CI, 9.2 to 17.7 months) compared with 20 months (95% CI, 12.7 months to not reached) for carboplatin plus paclitaxel (hazard ratio, 2.00; 95% CI, 1.15 to 3.47; P = .014). CONCLUSION This is the first international randomized trial to our knowledge conducted in chemotherapy-naïve advanced anal cancer. Although there was no difference in ORR, the association with clinically relevant reduced toxicity and a trend toward longer survival suggest that carboplatin plus paclitaxel should be considered as a new standard of care.

The presence of peritoneal metastases in patients with advanced colorectal cancer is associated with poor prognosis but the mechanisms for this are unclear. This review summarises the current knowledge of the pathophysiology, clinical features, prevalence, prognosis, and molecular biology of peritoneal metastases and the risk factors for the development of peritoneal metastases following resection of a primary colorectal tumour. Furthermore, the evidence for treatment strategies are described including cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, early post-operative intraperitoneal chemotherapy, sequential post-operative intraperitoneal chemotherapy and emerging novel strategies. Active areas of research should include the identification of individuals at high risk of peritoneal metastases after curative resection of primary tumour, development of a surveillance program for high-risk patients, optimisation of systematic therapies and further investigation of the use of intraperitoneal chemotherapy.

Background: GO2 sought to optimise chemotherapy dosing in older/frail patients with advanced gastroesophageal cancer, and explored baseline geriatric assessment (GA) as a tool for treatment decision-making. Methods: Patients were recruited for whom full-dose combination chemotherapy was considered unsuitable. Two randomisation options were available: CHEMO-INTENSITY compared oxaliplatin/capecitabine at Level A (doses as used in the standard epirubicin/oxaliplatin/capecitabine regimen), B (0·8x A) or C (0·6x A). Non-inferiority of PFS was assessed using boundary HR=1·34, selected by a forum of patients and clinicians. Overall Treatment Utility (OTU), which combines efficacy, toxicity, QL and patient value/acceptability, was scored at nine weeks. Alternatively, if the patient and clinician agreed the indication for chemotherapy was uncertain, they could enter the CHEMO-BSC randomisation, comparing Level C versus best supportive care. Findings: 514 patients entered the CHEMO-INTENSITY randomisation: non-inferior PFS was confirmed for B vs A (HR=1·09 [CI=0·89-1·32]) and C vs A (HR=1·10 [0·90-1·33]). Level C produced less toxicity and better OTU than A or B. No subgroup benefited from higher doses: Level C produced better OTU even in the younger, fitter patients. 45 patients entered the CHEMO-BSC randomisation: overall survival was non-significantly longer with chemotherapy: median 6·1 vs 3·0 months, HR=0·69 [0·32-1·48], p=0·34. In multivariate analysis, baseline frailty, QL and neutrophil:lymphocyte ratio were independently associated with OTU, so can be combined in a model to estimate the probability of better or worse outcome. Interpretation: Reduced-intensity chemotherapy provided non-inferior efficacy with an improved patient experience. Baseline geriatric assessment can help predict the utility of chemotherapy. Trial Registration: [Trial registration: ISRCTN44687907] Funding Statement: Cancer Research UK [CRUK/12/022] Declaration of Interests: Dr. Grabsch reports personal fees from Merck Sharpe Dome, outside the submitted work; all other authors have nothing to declare. Ethics Approval Statement: This study was approved by the UK National Research Ethics Service and overseen by independent Trial Steering and Data Monitoring & Ethics Committees (TSC; IDMC).

Background Immunohistochemical quantification of the immune response is prognostic for colorectal cancer (CRC). Here, we evaluate the suitability of alternative immune classifiers on prognosis and assess whether they relate to biological features amenable to targeted therapy. Methods Overall survival by immune (CD3, CD4, CD8, CD20 and FOXP3) and immune-checkpoint (ICOS, IDO-1 and PD-L1) biomarkers in independent CRC cohorts was evaluated. Matched mutational and transcriptomic data were interrogated to identify associated biology. Results Determination of immune-cold tumours by combined low-density cell counts of CD3, CD4 and CD8 immunohistochemistry constituted the best prognosticator across stage II–IV CRC, particularly in patients with stage IV disease (HR 1.98 [95% CI: 1.47–2.67]). These immune-cold CRCs were associated with tumour hypoxia, confirmed using CAIX immunohistochemistry (P = 0.0009), which may mediate disease progression through common biology (KRAS mutations, CRIS-B subtype and SPP1 mRNA overexpression). Conclusions Given the significantly poorer survival of immune-cold CRC patients, these data illustrate that assessment of CD4-expressing cells complements low CD3 and CD8 immunohistochemical quantification in the tumour bulk, potentially facilitating immunophenotyping of patient biopsies to predict prognosis. In addition, we found immune-cold CRCs to associate with a difficult-to-treat, poor prognosis hypoxia signature, indicating that these patients may benefit from hypoxia-targeting clinical trials.

Importance: Older and/or frail patients are underrepresented in landmark cancer trials. Tailored research is needed to address this evidence gap. Objective: The GO2 randomized clinical trial sought to optimize chemotherapy dosing in older and/or frail patients with advanced gastroesophageal cancer, and explored baseline geriatric assessment (GA) as a tool for treatment decision-making. Design, Setting, and Participants: This multicenter, noninferiority, open-label randomized trial took place at oncology clinics in the United Kingdom with nurse-led geriatric health assessment. Patients were recruited for whom full-dose combination chemotherapy was considered unsuitable because of advanced age and/or frailty. Interventions: There were 2 randomizations that were performed: CHEMO-INTENSITY compared oxaliplatin/capecitabine at Level A (oxaliplatin 130 mg/m 2on day 1, capecitabine 625 mg/m 2twice daily on days 1-21, on a 21-day cycle), Level B (doses 0.8 times A), or Level C (doses 0.6 times A). Alternatively, if the patient and clinician agreed the indication for chemotherapy was uncertain, the patient could instead enter CHEMO-BSC, comparing Level C vs best supportive care. Main Outcomes and Measures: First, broad noninferiority of the lower doses vs reference (Level A) was assessed using a permissive boundary of 34 days reduction in progression-free survival (PFS) (hazard ratio, HR = 1.34), selected as acceptable by a forum of patients and clinicians. Then, the patient experience was compared using Overall Treatment Utility (OTU), which combines efficacy, toxic effects, quality of life, and patient value/acceptability. For CHEMO-BSC, the main outcome measure was overall survival. Results: A total of 514 patients entered CHEMO-INTENSITY, of whom 385 (75%) were men and 299 (58%) were severely frail, with median age 76 years. Noninferior PFS was confirmed for Levels B vs A (HR = 1.09 [95% CI, 0.89-1.32]) and C vs A (HR = 1.10 [95% CI, 0.90-1.33]). Level C produced less toxic effects and better OTU than A or B. No subgroup benefited from higher doses: Level C produced better OTU even in younger or less frail patients. A total of 45 patients entered the CHEMO-BSC randomization: overall survival was nonsignificantly longer with chemotherapy: median 6.1 vs 3.0 months (HR = 0.69 [95% CI, 0.32-1.48], P =.34). In multivariate analysis in 522 patients with all variables available, baseline frailty, quality of life, and neutrophil to lymphocyte ratio were independently associated with OTU, and can be combined in a model to estimate the probability of different outcomes. Conclusions and Relevance: This phase 3 randomized clinical trial found that reduced-intensity chemotherapy provided a better patient experience without significantly compromising cancer control and should be considered for older and/or frail patients. Baseline geriatric assessment can help predict the utility of chemotherapy but did not identify a group benefiting from higher-dose treatment. Trial Registration: isrctn.org Identifier: ISRCTN44687907.

3504 Background: There is extensive randomised evidence supporting the use of treatment breaks in mCRC, but breaks from treatment are not universally offered to patients despite reductions in toxicity, without detriment to OS. Prior trials have shown that the combination of Cp and bevacizumab extend PFS but not OS. FOCUS4-N explores oral maintenance Cp monotherapy in patients with disease control on first line therapy. Methods: FOCUS4 was a molecularly stratified trial programme registering patients with newly diagnosed mCRC from 88 hospitals in the UK. Whilst undergoing 16 wks of first line treatment, a sample of tumour was sent for laboratory testing to stratify their disease into molecular subtypes: MSI, BRAF, PIK3CA, TP53 and RAS mutations. For some molecular groups, a targeted therapy subtrial was available but entry into the FOCUS4-N trial was offered to those in whom a targeted subtrial was unavailable. Patients were randomised 1:1 between maintenance Cp therapy or AM. The primary outcome was PFS assessed using 8-wkly RECIST reported CT scans with quality of life (using EQ5D 8 weekly) and OS as secondary outcomes. Toxicity and tolerability were assessed 4-wkly. On progression, from the nadir, patients recommenced first line treatment. Cox regression was used to assess efficacy by intention-to-treat (ITT) with adjustment for tumour location, WHO status, metastatic burden, first line treatment and biomarker subtype. Results: Between March 2014 and March 2020, 254 patients were randomised (127 to Cp and 127 to AM). Baseline characteristics were balanced between groups but event rates were higher than anticipated in the AM group and the final analysis was triggered early as a result of the COVID-19 pandemic halting recruitment. The table presents results for PFS and OS. Compliance with treatment was good with per-protocol analysis results very similar to ITT (PFS HR=0.38 (95% CI 0.28-0.51)). Toxicity from Cp v AM was as expected with G≥2 fatigue (25% v 12%), diarrhoea (23% v 13%) and hand-foot syndrome (26% v 3%). Quality of life showed no statistically significant differences between the two arms. Conclusions: Despite strong evidence of prolongation of PFS with maintenance therapy, OS remains unaffected and FOCUS4-N provides additional evidence to support the use of treatment breaks as a safe management alternative for patients who are stable or responding well to first line treatment for mCRC. Cp without bevacizumab may be used to extend PFS, in the interval after 16 weeks of combination therapy. Clinical trial information: ISRCTN#90061546. [Table: see text]

7009 Background: Survival outcomes of 2nd line mCRC therapy for OA are poorly understood. We evaluated the rates and survival outcomes of 2nd line therapy among OA age 70+ compared to younger adults (YA) age < 70 following progression on 1st line clinical trials. Methods: Associations between clinical characteristics of pts with available treatment data after progression on 10 of 23 1st line ARCAD trials, time to initial progression (TTiP) and 2nd line therapy were evaluated. Time to progression (TTP) and overall survival (OS) were compared between OA and YA enrolled on 2nd line trials by Cox regression, adjusting for age, sex, ECOG PS, number of metastatic sites, presence of metastasis in lung/liver/peritoneum. Results: Sixteen percent of 1st line ARCAD trial participants were age 70+ (n = 870). Data for 2nd line therapy was available for 60.6% pts (3206/5289). Each additional decade of life was associated with 11% lower odds of receiving 2nd line therapy in multivariate analysis (p = 0.0117). OA participating in 2nd line trials (7.9% age 75+ of 7921) experience similar TTP and OS to YA (mTTP: 5.1 vs. 5.2mos; mOS 11.6 vs 12.4mos, respectively). Conclusions: We did not observe a statistical difference in survival outcomes by age following 2nd line mCRC therapy. Further study is needed to examine unmeasured comorbidity and use of geriatric assessment to select OA likely to benefit from 2nd line therapy. [Table: see text]

Purpose: Patients with left-sided colon tumours have better survival and respond differently to biologics compared with patients with right-sided tumours. Left-sided colon tumours and rectal cancers are often grouped together. Herein, we examined the clinicopathological differences and outcomes between left-sided colon and rectal cancers.Patients and methods: Data from 2879 metastatic colorectal cancer patients enrolled on six first-line clinical trials during 2004–2010 were pooled. Patients were included if the primary tumour origin was clearly defined. Progression-free survival (PFS) and overall survival (OS) were compared in the two groups after adjusting for patient and tumour characteristics, metastatic sites and the first-line regimen.Results: In total, 1374 patients with metastatic left-sided colon cancer and 1505 patients with metastatic rectal cancers were evaluated. Left-sided colon cancer patients were more likely to be female (40.1% versus 32.6%; P < 0.0001) and older (31.0% ≥ 70 years versus 25.8%; P = 0.0033) compared with rectal cancers patients. Patients with left-sided colon cancer had higher rates of liver metastases (80.9% versus 72.3%, P < 0.0001) but lower rates of lung metastases (34.2% versus 53.8%, P < 0.0001). KRAS mutations were slightly less frequent among left-sided tumours (34.8% versus 40.5%; P = 0.0103). Patients with left-sided tumours had approximately similar PFS (median 7.4 versus 6.9 months; hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.87–1.03; P = 0.1998) and OS (median 17.4 versus 16.6 months; HR 0.99, 95% CI 0.91–1.07; P = 0.7597) compared with rectal cancer patients.Conclusion: The site of tumour origin within the left side was not prognostic of outcomes. Moreover, neither bevacizumab nor cetuximab impacted, differently, the findings of the comparisons in outcomes between patients with left-sided colon tumours or rectal cancers.

Background Many pts with aGOAC are elderly and/or frail. GO2 [ASCO 2019 #4006] found that lower dose OxaliplatinCapecitabine (OCap) led to non-inferior progression free survival, less toxicity and better patient-centred outcomes using a novel composite endpoint ‘Overall Treatment Utility’. QoL endpoints were chosen to reflect the balance between benefits and harms of the three dose levels and to help patients understand likely implications of treatment for shared decision making. Methods Eligible pts unsuitable for full-dose 3-drug chemotherapy due to frailty, but fit for OCap. Baseline assessment included QoL; symptoms; functional scales; comorbidity; frailty. Randomization was 1:1:1 to dose Level (Lvl) A (Ox 130 mg/m2d1, Cap 625 mg/m2bd d1-21, q21d), B (80% Lvl A doses) or C (60% Lvl A doses) until progression or decision to stop. An alternative randomisation option where chemo benefit was considered uncertain (‘uc’) was between OCap Lvl C and Best Supportive Care (BSC). QoL (EQ-VAS) was measured weekly during chemotherapy. QoL (EQ-5D), Fatigue (EORTC QLQ-C30 Fatigue scale) were measured 9-weekly for 1 year. QoL endpoints were analysed descriptively as pre-defined in the statistical analysis plan. Results 558 pts were enrolled, 2014-17, 61 UK centres, of which 45 pts were in the uc randomisation. Table . LBA46 Lvl A Lvl B Lvl C Lvl C (‘uc’) BSC (‘uc’) Pts 170 171 173 23 22 Median Age 76 76 77 79 79 % PS ≥ 2 31 32 31 57 68 % Severely Frail 61 56 58 70 68 9 wk Δ QLQ QoLa +0.4 +5.3 +4.9 na na 9 wk Δ EQ-5D QoLa -0.01 +0.06 +0.8 -0.19 -0.35 9 wk Δ EQ-VAS QoLa +8.6 +3.4 +5.4 +2.7 +0.2 9 wk Δ Fatigueb +8.6 +3.4 -0.6 +4.0 +15.1 Median TDFc (mths) 7.1 5.4 6.5 na na a. higher=better; b. higher=worse; c. TDF=Time to deterioration in fatigue Longitudinal QoL and Fatigue over the one year follow-up period were very similar between arms. Cancer symptoms also improved to a similar extend in each arm. Conclusions GO2 is the largest RCT to date investigating frail and/or elderly aGOAC pts, and should guide future treatment. Lower doses led to more rapid improvements in QoL and fatigue without compromising disease control or survival. Clinical trial identification EudraCT: 2013-000009-21; ISRCTN44687907 Rec No: 13/YH/0229. Legal entity responsible for the study University of Leeds. Funding Cancer Research UK. Disclosure All authors have declared no conflicts of interest.

Background:Estimating prognosis on the basis of clinicopathologic factors can inform clinical practice and improve risk stratification for clinical trials. We constructed prognostic nomograms for one-year overall survival and six-month progression-free survival in metastatic colorectal carcinoma by using the ARCAD database. Methods:Data from 22 674 patients in 26 randomized phase III clinical trials since 1997 were used to construct and validate Cox models, stratified by treatment arm within each study. Candidate variables included baseline age, sex, body mass index, performance status, colon vs rectal cancer, prior chemotherapy, number and location of metastatic sites, tumor mutation status (BRAF, KRAS), bilirubin, albumin, white blood cell count, hemoglobin, platelets, absolute neutrophil count, and derived neutrophil-to-lymphocyte ratio. Missing data (50% vs 50% vs

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers in Europe and worldwide, with the peak incidence in patients >70 years of age. However, as the treatment algorithms for the treatment of patients with CRC become ever more complex, it is clear that a significant percentage of older CRC patients (>70 years) are being less than optimally treated. This document provides a summary of an International Society of Geriatric Oncology (SIOG) task force meeting convened in Paris in 2013 to update the existing expert recommendations for the treatment of older (geriatric) CRC patients published in 2009 and includes overviews of the recent data on epidemiology, geriatric assessment as it relates to surgery and oncology, and the ability of older CRC patients to tolerate surgery, adjuvant chemotherapy, treatment of their metastatic disease including palliative chemotherapy with and without the use of the biologics, and finally the use of adjuvant and palliative radiotherapy in the treatment of older rectal cancer patients. An overview of each area was presented by one of the task force experts and comments invited from other task force members.

Purpose Progression-free survival (PFS) has previously been established as a surrogate for overall survival (OS) for first-line metastatic colorectal cancer (mCRC). Because mCRC treatment has advanced in the last decade with extended OS, this surrogacy requires re-examination. Methods Individual patient data from 16,762 patients were available from 22 first-line mCRC studies conducted from 1997 to 2006; 12 of those studies tested antiangiogenic and/or anti–epidermal growth factor receptor agents. The relationship between PFS (first event of progression or death) and OS was evaluated by using R2 statistics (the closer the value is to 1, the stronger the correlation) from weighted least squares regression of trial-specific hazard ratios estimated by using Cox and Copula models. Results Forty-four percent of patients received a regimen that included biologic agents. Median first-line PFS was 8.3 months, and median OS was 18.2 months. The correlation between PFS and OS was modest (R2, 0.45 to 0.69). Analyses limited to trials that tested treatments with biologic agents, nonstrategy trials, or superiority trials did not improve surrogacy. Conclusion In modern mCRC trials, in which survival after the first progression exceeds time to first progression, a positive but modest correlation was observed between OS and PFS at both the patient and trial levels. This finding demonstrates the substantial variability in OS introduced by the number of lines of therapy and types of effective subsequent treatments and the associated challenge to the use of OS as an end point to assess the benefit attributable to a single line of therapy. PFS remains an appropriate primary end point for first-line mCRC trials to detect the direct treatment effect of new agents.

Epidermal growth factor receptor (EGFR) (HER1) signaling depends on ligand binding and dimerization with itself or other HER receptors. We previously showed in a randomized trial that high EGFR ligand expression is predictive of panitumumab benefit in advanced colorectal cancer. Tumor expression of HER3 may further refine the RAS wild-type (wt) population benefitting from anti-EGFR agents.To examine HER3 messenger RNA expression as a prognostic and predictive biomarker for anti-EGFR therapy in a randomized clinical trial of panitumumab.The study was a prospectively planned retrospective biomarker study of pretreatment samples from the PICCOLO trial that tested the addition of panitumumab to irinotecan therapy in patients with KRAS wt advanced colorectal cancer who experienced failure with prior fluoropyrimidine treatment. HER3 was assessed as a prognostic marker, then as a predictive biomarker in patients with RAS wt, first as a continuous variable and then as a binary (high vs low) variable. Relationship with MEK-AKT pathway mutations and EGFR ligands epiregulin and amphiregulin (EREG/AREG) were also assessed.Primary end point was progression-free survival (PFS); secondary end points were response rate and overall survival (OS).In 308 patients (mean age at randomization, 61.6 years; 193 men) higher HER3 was weakly prognostic for OS (hazard ratio [HR] per 2-fold change, 0.91; 95% CI, 0.83-0.99; P = .04) but not PFS (HR, 0.93; 95% CI, 0.83-1.05; P = .25). Higher HER3 was predictive, being associated with prolonged PFS on irinotecan plus panitumumab (IrPan) (HR, 0.71; 95% CI, 0.61-0.82; P .001), but not irinotecan (HR, 0.96; 95% CI, 0.82-1.13; P = .65) in patients with RAS wt, with significant interaction between biomarker and treatment (P = .001). Similar interaction was seen for OS (P = .004). In an exploratory binary model, dividing the population at the 66th percentile, HER3 was predictive of panitumumab benefit: in patients with high HER3 expression, median PFS was 8.2 months (IrPan) vs 4.4 months (irinotecan) (HR, 0.33; 95% CI, 0.19-0.58; P .001). Patients with low HER3 expression gained no benefit in PFS: 3.3 months (IrPan) vs 4.3 months (irinotecan) (HR, 0.96; 95% CI, 0.67-1.38; P = .84), with significant interaction (P = .002). The binary model was also predictive for OS, with significant interaction (P = .01). Combining HER3 and ligand data, patients with HER3-high, AREG/EREG-high tumors gained markedly from panitumumab (PFS HR, 0.24; 95% CI, 0.11-0.51; P .005 and OS HR, 0.36; 95% CI, 0.18-0.73; P = .004). Conversely, patients with HER3-low, AREG/EREG-low tumors did not benefit (PFS HR, 1.14; 95% CI, 0.73-1.79; P = .57 and OS HR, 1.44; 95% CI, 0.92-2.26; P = .11).High HER3 expression identified patients with RAS wt who gained markedly from panitumumab, and those who did not, with statistically significant biomarker-treatment interactions for PFS and OS. This finding provides insight into the mechanism of anti-EGFR agents and is of potential clinical utility.

AIM: To investigate the impact of histology on outcome in advanced oesophageal cancer treated with first-line fluoropyrimidine-based chemotherapy. METHODS: Individual patient data were pooled from three randomised phase III trials of fluoropyrimidine-based chemotherapy ± platinum/anthracycline in patients with advanced, untreated gastroesophageal adenocarcinoma or squamous cell carcinoma (SCC) randomised between 1994 and 2005. The primary endpoint was overall survival of oesophageal cancer patients according to histology. Secondary endpoints were response rates and a toxicity composite endpoint. RESULTS: Of the total 1836 randomised patients, 973 patients (53%) were eligible (707 patients with gastric cancer were excluded), 841 (86%) had adenocarcinoma and 132 (14%) had SCC. There was no significant difference in survival between patients with adenocarcinoma and SCC, with median overall survivals of 9.5 mo vs 7.6 mo (HR = 0.85, 95%CI: 0.70-1.03, P = 0.09) and one-year survivals of 38.8% vs 28.2% respectively. The overall response rate to chemotherapy was 44% for adenocarcinoma vs 33% for SCC (P = 0.01). There was no difference in the frequency of the toxicity composite endpoint between the two groups. CONCLUSION: There was no significant difference in survival between adenocarcinoma and SCC in patients with advanced oesophageal cancer treated with fluoropyrimidine-based chemotherapy despite a trend for worse survival and less chemo-sensitivity in SCC. Tolerance to treatment was similar in both groups. This analysis highlights the unmet need for SCC-specific studies in advanced oesophageal cancer and will aid in the design of future trials of targeted agents.

Contains fulltext : 182283.pdf (Publisher’s version ) (Open Access) Diversity in colorectal cancer biology is associated with variable responses to standard chemotherapy. We aimed to identify and validate DNA hypermethylated genes as predictive biomarkers for irinotecan treatment of metastatic CRC patients. Candidate genes were selected from 389 genes involved in DNA Damage Repair by correlation analyses between gene methylation status and drug response in 32 cell lines. A large series of samples (n=818) from two phase III clinical trials was used to evaluate these candidate genes by correlating methylation status to progression-free survival after treatment with first-line single-agent fluorouracil (Capecitabine or 5-fluorouracil) or combination chemotherapy (Capecitabine or 5-fluorouracil plus irinotecan (CAPIRI/FOLFIRI)). In the discovery (n=185) and initial validation set (n=166), patients with methylated Decoy Receptor 1 (DCR1) did not benefit from CAPIRI over Capecitabine treatment (discovery set: HR=1.2 (95%CI 0.7-1.9, p=0.6), validation set: HR=0.9 (95%CI 0.6-1.4, p=0.5)), whereas patients with unmethylated DCR1 did (discovery set: HR=0.4 (95%CI 0.3-0.6, p=0.00001), validation set: HR=0.5 (95%CI 0.3-0.7, p=0.0008)). These results could not be replicated in the external data set (n=467), where a similar effect size was found in patients with methylated and unmethylated DCR1 for FOLFIRI over 5FU treatment (methylated DCR1: HR=0.7 (95%CI 0.5-0.9, p=0.01), unmethylated DCR1: HR=0.8 (95%CI 0.6-1.2, p=0.4)). In conclusion, DCR1 promoter hypermethylation status is a potential predictive biomarker for response to treatment with irinotecan, when combined with capecitabine. This finding could not be replicated in an external validation set, in which irinotecan was combined with 5FU. These results underline the challenge and importance of extensive clinical evaluation of candidate biomarkers in multiple trials.

To improve strategies for the treatment of BRAF-mutant advanced colorectal cancer (aCRC) patients, we examined individual data from patients treated with chemotherapy alone in three randomised trials to identify points on the treatment pathway where outcomes differ from BRAF wild-types.2530 aCRC patients were assessed from three randomised trials. End-points were progression-free survival, response rate, disease control rate, post-progression survival (P-PS) and overall survival. Treatments included first-line oxaliplatin/fluorouracil (OxFU) and second-line irinotecan. Clinicians were unaware of BRAF-status.231 patients (9.1%) had BRAF-mutant tumours. BRAF-mutation conferred significantly worse survival independent of associated clinicopathological factors known to be prognostic. Compared with wild-type, BRAF-mutant patients treated with first-line OxFU had similar DCR (59.2% versus 72%; adjusted OR = 0.76, P = 0.24) and PFS (5.7 versus 6.3 months; adjusted HR = 1.14, P = 0.26). Following progression on first-line chemotherapy, BRAF-mutant patients had a markedly shorter P-PS (4.2 versus 9.2 months, adjusted HR = 1.69, P 6 months; OS = 24.0 months); however, 36.5% progressed rapidly through first-line chemotherapy and thereafter, with OS = 4.7 months.BRAF-mutant aCRC confers a markedly worse prognosis independent of associated clinicopathological features. Chemotherapy provides meaningful improvements in outcome throughout treatment lines. Post-progression survival is markedly worse and vigilance is required to ensure appropriate delivery of treatment after first-line progression.

Background: The tumor microenvironment is a key feature to understand cancer biology and may be used clinically. Quantification of tissue composition is usually based either on visual pathological review (VPR) or deconvolution of whole genome molecular data. Although the former is a direct measurement it has modest reproducibility while the latter is an indirect measurement of unclear accuracy, expensive and not always available. Here we test digital pathology coupled with machine learning as a new tool to assess tissue composition. Methods: As part of the Stratification in COloRecTal cancer (S:CORT) programme, a set of over 500 colorectal cancer (CRC) archival paraffin blocks from resections and biopsies were sequentially sectioned for Hematoxylin and Eosin staining (H&E), RNA extraction, a second H&E and DNA extraction. RNA expression microarrays, targeted DNA sequencing and DNA methylation arrays were applied. Tissue composition from the H&Es was obtained by VPR of expert pathologists and by a deep neural net (DNN) algorithm after supervised training on >1,500 tissue areas from S:CORT, TCGA, TEM and CORGI CRC cohorts. Tumor purity estimates were obtained from RNA and methylation arrays. Results: DNN estimates including area and cell counts were obtained for tumor, desmoplastic stroma, inflamed stroma, mucin/hypocellular stroma, muscle, necrosis and white space. An average of 6.8x105 total cells (range: 1.2x104-2.8x106) and 1.2x105 (range: 7.2x104-1.8x106) were classified for resections and biopsies respectively. Analyses performed twice on the same H&Es obtained matching results (r=1.0). Comparison of the paired first and second H&E showed very high correlations (r~0.9) and total cell counts correlated with DNA and RNA extraction yields (r~0.6). Tumor purity estimates by VPR mildly correlated with DNN (r~0.5) but they were underestimated and very variable. As a result, copy number adjusted by VPR purity tended to be overestimated compared to adjustment with DNN estimates. The improved performance of DNN is reflected in an accurate capture of non-linear association between area and cell counts in invasive cancer. In contrast, tumor purity estimates derived from RNA or DNA methylation arrays showed better correlations compared with DNN (r~0.6) but both overestimated purity in cases with low cell counts by up to a three-fold difference. Conclusions: Tissue composition analysis with DNN allows analytical robustness, automatization and standardization and provides very high reproducibility at single cell resolution. DNN-based estimation of tumor purity is more accurate than VPR or extrapolation from molecular data derived from genome-wide omic platforms which tend to under and overestimate tumor purity respectively. DNN could be used to better plan and asses downstream molecular analyses and to investigate tissue-based metrics as potential clinical biomarkers in clinical trials. Citation Format: Enric Domingo, Aikaterini Chatzipli, Susan Richman, Andrew Blake, Claire Hardy, Celina Whalley, Keara Redmon, Ian Tomlinson, Philip Dunne, Steven Walker, Andrew Beggs, Ultan McDermott, Graeme I. Murray, Leslie M. Samuel, Matthew Seymour, Philip Quirke, Tim Maughan, Viktor H. Koelzer. Assessment of tissue composition with digital pathology in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4446.

4006 Background: Many pts with aGOAC are elderly and/or frail. We previously compared epirubin/ oxaliplatin/ capecitabine (EOCap) vs OCap vs Cap in a pick-the-winner study and found OCap best. GO2 was designed to find the optimum dose of OCap and to explore the use of an objective baseline geriatric assessment to individualize doses for maximum Overall Treatment Utility (OTU), a composite of clinical benefit, tolerability, QL and patient value. Methods: Pts with aGOAC were eligible if unsuitable for full-dose EOCap due to age or frailty, but fit for OCap; GFR ≥ 30, bili 2d1, Cap 625 mg/m2bd d1-21, q21d), B (80% Level A doses) or C (60% Level A doses). Pts with GFR 30-50 ml/min or bili 1.5-2.0 xULN received 75% of the allocated dose of Cap. At 9 wks, pts were scored for OTU. Continuation thereafter was based on clinical judgement. Non-inferiority (vs A) was assessed using PFS censored at 12 months, with boundary HR 1.34 (based on discussion with pts and clinicians), needing 284 PFS events per 2-way comparison. Baseline fitness was assessed as predictive of OTU, overall and by interaction with dose level. Results: 514 pts were randomised, 2014-17, at 61 UK centres. Clinical trial information: 44687907. Non-inferiority of PFS is confirmed for Level B vs A (HR 1.09, CI 0.89-1.32) and for Level C vs A (HR 1.10, CI 0.90-1.33). Level C pts had less toxicity and better OTU outcomes than A or B. When analysed by baseline age, frailty and PS, Level C produced the best OTU even in younger, less frail and better PS patients; no group was identified who benefit more from the higher dose levels. Conclusions: This is the largest RCT to date specifically investigating frail and/or elderly aGOAC pts, and should guide future treatment. The lowest dose tested was non-inferior in terms of PFS and produced less toxicity and better overall treatment utility.[Table: see text]

4051 Background: Before 2000, trials comparing BSC +/- chemo for aGOAC showed overall survival (OS) benefit, but in predominantly fit patients (pts). We have revisited this question in a modern context, using low-dose chemo in a frail population, with comprehensive baseline health and frailty assessment. Methods: In the GO2 trial, elderly and/or frail aGOAC pts with a “certain” indication for chemo were randomised between 3 chemo doses. In this GO2 substudy, pts with an “uncertain” indication for chemo were instead randomised to BSC ± the lowest dose chemo. Pts were eligible if clinician and pt agreed the indication for chemo was uncertain. There was no PS threshold, but eGFR ≥30 and bili < 2xULN were required. Baseline assessment included global QL, symptom & functional scales, frailty and comorbidity. Randomisation was 1:1 to BSC alone, or with oxaliplatin 78 mg/m2 d1, capecitabine 375 mg/m2 bd d1-21 (modified if eGFR 30-50 ml/min or bili 1.5-2.0 xULN), q21d. QL was reassessed after 9 and 18 wks. The primary endpoint analysis was OS, adjusted for baseline factors. The sample size for this exploratory sub-study was not pre-set, but around 60 pts were anticipated. Results: 558 pts entered GO2 at 61 centres 2014-17, of whom only 45 pts (8%) at 21 centres entered this uncertain randomisation. This would provide 80% power at p = 0.05 (2-tailed) to detect an OS HR of 0.3. OS was shorter in pts with worse baseline PS (p0.32. QL deteriorated less with BSC+chemo than with BSC alone. Conclusions: In this frail, poor PS population, we observed a small survival benefit with chemo but this did not reach statistical significance. Clinicians should carefully consider BSC alone as a valid treatment option for aGOAC pts with poor PS and/or frailty. Clinical trial information: 44687907. [Table: see text]

3504 Background: NAC is well established in many solid tumours but has not undergone large-scale evaluation in colon cancer. Methods: Pts had operable, non-obstructed colon cancer; CT-predicted stage T3-4, N0-2, M0, and were fit for FOLFOX and surgery. They were randomised 2:1 to the novel sequence (6 wk FOLFOX NAC, then surgery, then 18 wk FOLFOX) or control (surgery then 24 wk FOLFOX). RAS-wt pts allocated to the novel arm could optionally be sub-randomized 1:1 to ± panitumumab (pan) during the NAC phase. Two "dealer’s choices" allowed total chemo duration 12 wk instead of 24 (in older/low-risk pts) and OxCap in place of FOLFOX (except in pts randomized ± pan). Primary endpoint is freedom from recurrent or persistent disease after 2 yrs, by ITT. Secondary endpoints include safety, histological stage, completeness of resection, OS. Results: 1052 pts were randomised, Jun 2008-Dec 2016, at 85 centres in UK, Denmark and Sweden. Conclusions: NAC was well tolerated and safe, with no increase in perioperative morbidity and a trend toward fewer serious postoperative complications. Evidence of histological regression was seen in 59% pts after NAC, including some pCRs. This resulted in marked histological downstaging and a halving of the rate of incomplete resections. We observed an improvement in 2-yr failure rate (HR=0.77), but this fell short of statistical significance (p=0.11). NAC for colon cancer improves surgical outcomes and can now be considered as a treatment option; longer follow-up and further trials are required to confirm the long-term benefits, refine its use and optimise case selection. Clinical trial information: 87163246. [Table: see text]

3568 Background: Preoperative CT and radiotherapy are surprisingly more effective than postoperative treatment in rectal and other cancers, perhaps because micrometastases are more readily eradicat...

Purpose Uncertainty exists about whether elderly patients benefit to the same extent as younger patients from combination therapy with irinotecan in the first-line treatment of metastatic colorectal cancer (CRC). Patients and Methods Combined analysis was carried out with source data from the fluorouracil (FU)/folinic acid (FA) and the irinotecan/FU/FA arms of four first-line, phase III trials of CRC to investigate the efficacy and safety of combination and monotherapy in elderly (age ≥ 70 years; n = 599) compared with younger (age < 70 years; n = 2,092) patients. Results Response rates were improved with irinotecan-based combination therapy compared with FU/FA in patients both younger than 70 years and ≥ 70 years (46.6% v 29.0% P < .0001; and 50.5% v 30.3%, P < .0001, respectively). With irinotecan/FU/FA, progression-free survival was better for both younger (hazard ratio [HR], 0.77; 95% CI, 0.70 to 0.85; P < .0001) and elderly patients (HR, 0.75; 95% CI, 0.61 to 0.90; P = .0026). In younger patients, overall survival was improved with combination therapy (HR, 0.83; 95% CI, 0.75 to 0.92; P = .0003). The same trend was observed in elderly patients (HR, 0.87; 95% CI, 0.72 to 1.05; P = .15). There was no significant interaction between treatment arm and age in the regression analysis. The expected differences in toxicity between combination and monotherapy in elderly and younger patients were observed. A significant interaction between treatment and age (cutoff, 70 years) for vomiting and hepatotoxicity was not confirmed by analysis that used age as a continuous variable. Conclusion Patients older than 70 years of age who were selected for inclusion in phase III trials derived similar benefits as younger patients from irinotecan-containing chemotherapy, and the risk of toxicity was similar.

BACKGROUND: This randomised trial compared three chemotherapy regimens in the first-line treatment of advanced colorectal cancer, in terms of their effect on overall and progression-free survival; other endpoints included toxicity, symptom palliation, and quality of life. METHODS: 905 patients were randomly assigned the de Gramont regimen (n=303; folinic acid 200 mg/m(2), fluorouracil bolus 400 mg/m(2), and infusion 600 mg/m(2) on days 1 and 2, repeated every 14 days), the Lokich regimen (n=301; protracted venous infusion of fluorouracil 300 mg/m(2) daily), or raltitrexed (n=301; 3 mg/m(2) intravenously every 21 days). Analyses were by intention to treat. FINDINGS: Median follow-up of survivors was 67 weeks. For the de Gramont, Lokich, and raltitrexed groups, respectively, median survival was 294, 302, and 266 days. The hazard ratios for overall survival were 0.88 (95% CI 0.70-1.12, p=0.17) for de Gramont versus Lokich, and 0.99 (0.79-1.25, p=0.94) for de Gramont versus raltitrexed. An increase in treatment-related deaths was seen on raltitrexed (de Gramont one, Lokich two, raltitrexed 18) due to combined gastrointestinal and haematological toxicity. Patients' assessment of quality of life showed that raltitrexed was inferior to the fluorouracil-based regimens, especially in terms of palliation and functioning. INTERPRETATION: The deGramont and Lokich regimens were similar in terms of survival, quality of life, and response rates. The Lokich regimen was associated with more central line complications and hand-foot syndrome. Raltitrexed showed similar response rates and overall survival to the de Gramont regimen and was easier to administer, but resulted in greater toxicity and inferior quality of life.

Purpose In recent retrospective analyses of early-stage colorectal cancer (CRC), low and high body mass index (BMI) scores were associated with worsened outcomes. Whether BMI is a prognostic or predictive factor in metastatic CRC (mCRC) is unclear. Patients and Methods Individual data from 21,149 patients enrolled onto 25 first-line mCRC trials during 1997 to 2012 were pooled. We assessed both prognostic and predictive effects of BMI on overall survival and progression-free survival, and we accounted for patient and tumor characteristics and therapy type (targeted v nontargeted). Results BMI was prognostic for overall survival (P < .001) and progression-free survival (P < .001), with an L-shaped pattern. That is, risk of progression and/or death was greatest for low BMI; risk decreased as BMI increased to approximately 28 kg/m2, and then it plateaued. Relative to obese patients, patients with a BMI of 18.5 kg/m2 had a 27% increased risk of having a PFS event (95% CI, 20% to 34%) and a 50% increased risk of death (95% CI, 43% to 56%). Low BMI was associated with poorer survival for men than women (interaction P < .001). BMI was not predictive of treatment effect. Conclusion Low BMI is associated with an increased risk of progression and death among the patients enrolled on the mCRC trials, with no increased risk for elevated BMI, in contrast to the adjuvant setting. Possible explanations include negative effects related to cancer cachexia in patients with low BMI, increased drug delivery or selection bias in patients with high BMI, and potential for an interaction between BMI and molecular signaling pathways.

Personalized medicine appears to be the inevitable consequence of improvements in our understanding of the mechanisms of action of chemotherapeutic agents, as well as the description of the human genome and its impact on our understanding of the genes involved in DNA repair and drug metabolism. These rapid developments have been associated with the first efforts to establish genetic predictors of chemotherapy efficacy and toxicity for the chemotherapy drugs active in colorectal cancer—fluorouracil, irinotecan, and oxaliplatin.

Whilst advanced squamous cell carcinoma of the anal canal (SCCA) is a rare disease incidence has risen by 2%/year for the past decade. There is no consensus on management of these pts who generally have a poor overall survival (OS) and to date no randomised trial has been completed. The combination of fluoropyrimidine /platinum agents is often considered standard 1st line therapy whilst taxanes have shown activity. We conducted a randomised phase II study to establish a standard of care.

e15635Background: High peripheral blood NLR is a poor prognostic marker in cancer patients. We investigated the relationship between NLR and measured IRs in patients with chemo-naive aCRC and the m...

Biomarkers with predictive value and, to a lesser extent, prognostic value hold the potential to revolutionize the clinical practice of oncology. During the past 20 years, this has been an active field for basic and translational research in colorectal cancer, but no validated biomarkers have been identified or have become routine tools in clinical practice. The past decade has seen significant developments, with translational research projects being allied to randomized trials and the first fruit being borne with the identification of mismatch repair status, KRAS mutations, and possibly topoisomerase 1 expression as biomarkers with the potential to guide clinical practice.

617 Background: There is limited, often conflicting evidence about AE timing, severity or associations with outcomes with the use of cytotoxic agents in cancer treatment. We investigated the impact on overall survival (OS) and progression-free survival (PFS) of selected common AEs (neutropenia, diarrhea, nausea, vomiting, neuropathy) occurring in patients receiving first line oxaliplatin (Oxa)- and/or irinotecan(Iri)-based regimens for mCRC. Methods: The CTCAE grading scores of at least one AE of interest were available on 9812 pts treated with chemotherapy alone (median age 63; 62.4% male, 50.1% ECOG PS 0) from 17 1st-line randomized trials. Patients who also received biologics were excluded in the primary analyses. AEs occurring during the first 6 weeks of treatment and entire treatment were analyzed by stratified multivariable Cox models in relationship to OS/PFS. 55.7% pts received Oxa- regimens, 35.7% Iri-regimens, and 8.6% combined Oxa- and Iri-regimens. Results: Within the first 6 weeks of treatment, G3+ neutropenia (HRadj= 1.3, 95% CI, 1.06-1.59, padj 0.01), diarrhea (HRadj= 1.48, 95% CI, 1.23-1.79, padj < .0001), nausea (HRadj= 1.53, 95% CI, 1.17-1.99, padj 0.002) and vomiting (HRadj= 1.56, 95% CI, 1.18-2.07, padj 0.002) were associated with significantly worse OS for Iri-regimens, but only G3+ nausea predicted for worse OS for Oxa- regimens (HRadj= 1.61, 95% CI, 1.18-2.21, padj 0.003). For AEs experienced at any time, G3+ neutropenia and neuropathy were significantly associated with longer PFS and OS for Oxa-regimens, while G3+ vomiting and nausea were associated with worse OS for both Oxa- and Iri-based regimens. Sensitivity analysis showed largely concordant results by including pts who also received biologics. Conclusions: The association between more severe selected AEs and outcome varies between AEs and is influenced by timing of the occurrence. More severe selected AEs occurring early in treatment are associated with worse outcomes. In contrast, for AEs occurring at any time, G3+ neutropenia and neuropathy predicted for longer PFS and/or OS in Oxa-treated pts.

Background: it is unclear if differential chemotherapy effects exist on overall survival (OS), response rate (RR) and toxicity depending on primary tumour origin [oesophageal versus oesophago–gastric junction (OGJ) versus gastric adenocarcinoma]. Patients and methods: a total of 2110 patients were enrolled in four randomised controlled trials (RCTs) assessing fluoropyrimidine ± platinum-based chemotherapy. This analysis used individual patient data and restricted to patients with adenocarcinoma who received one or more dose of chemotherapy. Gastric origin was the control in comparisons of tumour origin. Results: of the 2110 patients randomised, 1775 (84%) patients had adenocarcinoma with oesophageal (n?=?485), OGJ (n?=?457) and gastric (n?=?833) origins. The median OS was 9.5 months in oesophageal, 9.3 months in OGJ and 8.7 months in gastric cancer (P?=?0.68). RR was 44.1% in oesophageal, 41.1% in OGJ and 35.6% in gastric cancers (P?=?0.11 and 0.27, respectively, compared with gastric cancer on multivariate analysis). Toxicity composite end point occurred in 46%, 47% and 45% in oesophageal, OGJ and gastric cancers, respectively (P?=?0.85 and 0.62 compared with gastric). Conclusions: in our large multicentre RCT dataset, no significant differences were demonstrated on multivariate analyses in OS, RR and toxic effects among patients with advanced oesophageal, OGJ and gastric adenocarcinoma. Future RCTs should not exclude oesophageal adenocarcinoma

With an increasing number of options now available for the management of metastatic colorectal cancer (mCRC), clinicians face the challenge of how to use them most effectively. First-line cytotoxic ‘doublets’ increase response rates and time to progression compared with monotherapy. However, five recent studies showed no significant overall survival benefit for first-line combination therapy compared with a pre-planned sequential approach starting with fluoropyrimidine monotherapy. In one trial, initial fluorouracil (FU)/irinotecan doublet therapy was superior to sequential FU then irinotecan, but the same trial showed non-inferiority for the sequential approach if a doublet was used second-line. Sub-group analyses failed to identify a subgroup benefiting from the initial doublet approach, although a trend towards benefit was seen for patients with poor performance status and some promising data suggest that predictive biomarkers may have a role in selecting the optimum strategy. The management of mCRC needs to consider the requirements of the individual patient and the whole course of treatment rather than a single line of therapy. Findings to date suggest that planned sequential therapy is a good option for many patients.

About 10 years ago, it was established that chemotherapy “doublets” of a fluoropyrimidine and either irinotecan or oxaliplatin give a higher response rate and longer progression-free survival than single-agent therapy. Some trials also showed overall surivval benefit, but others did not. Several large, randomized trials were set up between 2000 and 2003 in which prospective treatment plans involving initial doublet therapy were compared with plans using the same drugs but starting with single-agent fluoropyrimidine. Two—FOCUS and CAIRO—have now been published, and three others—FOCUS2, FFCD2000-05, and LIFE—have been reported in abstract form. Contrary to expectations, none has shown a clear survival benefit for the first-line combination chemotherapy arm. This article discusses the trial results and implications for practice.

Purpose Candidate predictive biomarkers for irinotecan and oxaliplatin were assessed in 1,628 patients in Fluorouracil, Oxaliplatin, CPT-11: Use and Sequencing (FOCUS), a large randomized trial of fluorouracil alone compared with fluorouracil and irinotecan and compared with fluorouracil and oxaliplatin in advanced colorectal cancer. Methods The candidate biomarkers were: tumor immunohistochemistry for MLH1/MSH2, p53, topoisomerase-1 (Topo1), excision repair cross-complementing gene 1 (ERCC1), O-6-methylguanine-DNA-methyltranserase (MGMT), and cyclooxygenase 2 (COX2); germline DNA polymorphisms in GSTP1, ABCB1, XRCC1, ERCC2, and UGT1A1. These were screened in more than 750 patients for interaction with benefit from irinotecan or oxaliplatin; two markers (Topo1 and MLH1/MSH2) met criteria to be taken forward for analysis in the full population. Primary end points were progression-free survival (PFS) and overall survival. Results One thousand three hundred thirteen patients (81%) were assessable for Topo1 immunohistochemistry (low, < 10%; moderate, 10% to 50%; or high, > 50% tumor nuclei). In patients with low Topo1, PFS was not improved by the addition of either irinotecan (hazard ratio [HR], 0.98; 95% CI, 0.78 to 1.22) or oxaliplatin (HR, 0.85; 95% CI, 0.68 to 1.07); conversely, patients with moderate/high Topo1 benefited from the addition of either drug (HR, 0.48 to 0.70 in all categories; interaction P = .005; overall, P = .001 for irinotecan; P = .05 for oxaliplatin). High Topo1 was associated with a major overall survival benefit with first-line combination chemotherapy (HR, 0.60; median benefit, 5.3 months); patients with moderate or low Topo1 did not benefit (HR, 0.92 and 1.09, respectively; interaction P = .005). MLH1/MSH2 did not show significant interaction with treatment, although the low rate of loss (4.4%) limits the power of the study for this biomarker. Conclusion Topo1 immunohistochemistry identified subpopulations that did or did not benefit from irinotecan, and possibly also from oxaliplatin. If verified independently, this information will contribute to the individualization of treatment for colorectal cancer.

Summary Background In the non-curative setting, the sequence in which anticancer agents are used, singly or in combination, may be important if patients are to receive the maximum period of disease control with the minimum of adverse effects. We compared sequential and combination chemotherapy strategies in patients with unpretreated advanced or metastatic colorectal cancer, who were regarded as not potentially curable irrespective of response. Methods We studied patients with advanced colorectal cancer, starting treatment with non-curative intent. 2135 unpretreated patients were randomly assigned to three treatment strategies in the ratio 1:1:1. Strategy A (control group) was single-agent fluorouracil (given with levofolinate over 48 h every 2 weeks) until failure, then single-agent irinotecan. Strategy B was fluorouracil until failure, then combination chemotherapy. Strategy C was combination chemotherapy from the outset. Within strategies B and C, patients were randomly assigned to receive, as the combination regimen, fluorouracil plus irinotecan (groups B-ir and C-ir) or fluorouracil plus oxaliplatin (groups B-ox and C-ox). The primary endpoint was overall survival, analysed by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN 79877428. Results Median survival of patients allocated to control strategy A was 13·9 months. Median survival of each of the other groups was longer (B-ir 15·0, B-ox 15·2, C-ir 16·7, and C-ox 15·4 months). However, log-rank comparison of each group against control showed that only C-ir—the first-line combination strategy including irinotecan—satisfied the statistical test for superiority (p=0·01). Overall comparison of strategy B with strategy C was within the predetermined non-inferiority boundary of HR=1·18 or less (HR=1·06, 90% CI 0·97–1·17). Interpretation Our data challenge the assumption that, in this non-curative setting, maximum tolerable treatment must necessarily be used first-line. The staged approach of initial single-agent treatment upgraded to combination when required is not worse than first-line combination, and is an alternative option for discussion with patients.

Purpose: Genome-wide association studies have identified numerous loci associated with colorectal cancer risk. Several of these have also been associated with patient survival, although none have been validated. Here, we used large independent training and validation cohorts to identify robust prognostic biomarkers for colorectal cancer. Experimental Design: In our training phase, we analyzed 20 colorectal cancer-risk SNPs from 14 genome-wide associated loci, for their effects on survival in 2,083 patients with advanced colorectal cancer. A Cox survival model was used, stratified for treatment, adjusted for known prognostic factors, and corrected for multiple testing. Three SNPs were subsequently analyzed in an independent validation cohort of 5,552 colorectal cancer patients. A validated SNP was analyzed by disease stage and response to treatment. Results: Three variants associated with survival in the training phase; however, only rs9929218 at 16q22 (intron 2 of CDH1, encoding E-cadherin) was significant in the validation phase. Patients homozygous for the minor allele (AA genotype) had worse survival (training phase HR, 1.43; 95% confidence intervals; CI, 1.20–1.71, P = 5.8 × 10−5; validation phase HR, 1.18; 95% CI, 1.01–1.37, P = 3.2 × 10−2; combined HR, 1.28; 95% CI, 1.14–1.43, P = 2.2 × 10−5). This effect was independent of known prognostic factors, and was significant amongst patients with stage IV disease (P = 2.7 × 10−5). rs9929218 was also associated with poor response to chemotherapy (P = 3.9 × 10−4). Conclusions: We demonstrate the potential of common inherited genetic variants to inform patient outcome and show that rs9929218 identifies approximately 8% of colorectal cancer patients with poor prognosis. rs9929218 may affect CDH1 expression and E-cadherin plays a role in epithelial-to-mesenchymal transition providing a mechanism underlying its prognostic potential. Clin Cancer Res; 21(15); 3453–61. ©2015 AACR.

For many years, the standard treatment for stage III colon cancer has been surgical resection followed by 5-fluorouracil in combination with folinic acid (5-FU/LV). Ongoing clinical trial evidence suggests that capecitabine and oxaliplatin (in combination with 5-FU/LV) may improve disease-free survival and overall survival when compared against 5-FU/LV alone in the adjuvant setting. This study evaluates the cost-effectiveness profiles of these two regimens in comparison to standard chemotherapy, using evidence from two international randomised controlled trials. Survival modelling techniques were employed to extrapolate survival curves from the two trials in order to estimate the long-term benefits of alternative treatment options over the remaining lifetime of patients. The health economic analysis suggests that capecitabine is expected to produce greater health gains at a lower cost than 5-FU/LV. Oxaliplatin in combination with 5-FU/LV is estimated to cost pounds 2970 per additional QALY gained when compared to 5-FU/LV alone. Future research should attempt to elucidate uncertainties concerning the optimal roles of capecitabine and/or oxaliplatin in the adjuvant setting in order to achieve the maximum level of clinical benefit.

We investigated 2-weekly intravenous irinotecan combined with oral capecitabine in patients with advanced gastroesophageal adenocarcinoma. In phase I, doses were escalated in chemotherapy naïve or pretreated patients to establish maximum tolerated doses (MTD). In phase II, patients were treated at MTD as first-line therapy with the primary end point of RECIST response. Dose levels in phase I were as follows: Level 1: irinotecan 150 mg m−2 on day 1; capecitabine 850 mg m−2 12-hourly on days 1–9. Level 2: as level 1 but capecitabine 1000 mg m−2. Level 3: as level 2 but irinotecan 180 mg m−2. Level 4: as level 3 but capecitabine 1250 mg m−2. In phase I, 21 patients were entered. Maximum tolerated dose was level 3. Dose-limiting toxicities were lethargy, diarrhoea, vomiting and mucositis. In phase II, 31 patients were entered at level 3. During the first six cycles, 13 of these patients underwent dose reduction and three patients stopped treatment for toxicity. A further six patients stopped for progressive disease. The commonest grade 3–4 toxicities were lethargy (20%), diarrhoea (17%), nausea (10%) and anorexia (10%). There were no treatment-related deaths. The response rate was 32% (95% CI 16–52%). Median overall survival was 10 months. This regimen is active in gastroesophageal adenocarcinoma. However, using the MTD defined in phase I, fewer than 50% patients tolerated six cycles without modification in phase II; therefore, modification of these doses is recommended for further study.

Background Current standard therapy following resection of high-risk colon cancer is intravenous bolus5-fluorouracil (5-FU) with leucovorin (LV), but there is no consensus on the optimum regimen of these drugs: practice ranges from the high toxicity Mayo Clinic schedule to the very low toxicity weekly QUASAR schedule. We present data for a weekly schedule that aims to provide moderately dose-intense treatment with low toxicity. Patients and methods One hundred and sixty-two patients were studied: 60% male; median age 65 years (36% over 70 years); 94% colorectal primary. Treatment was intravenous bolus (5 min) 5-FU 425 mg/m2 plus d , l -LV 45 mg flat rate once weekly, for a planned 24 weeks. Data for toxicity, dose-reductions, delays and stoppages were collected. Results Overall, 20% of patients experienced any grade ≥3 toxicity, most commonly diarrhoea (14% patients). Dose reductions were made in 35% of patients (although only 21% required 20% or more reduction); toxicity contributed to a decision to stop treatment before 24 weeks in 16% of patients. Median delivered dose intensity (DI) was 96% of planned (407 mg/m2/week) during treatment, and 91% of planned (385 mg/m2/week) over the full 24 week treatment plan. Female sex and age >70 years were significantly associated with higher rates of toxicity and dose adjustment, and lower delivered DI. Conclusions Weekly treatment at these doses is convenient and well-tolerated for the large majority of patients, and achieves DI comparable with the 5 days a month QUASAR schedule and other more toxic standard regimens.

We previously reported high activity for oxaliplatin and a modified de Gramont regimen (OxMdG) in a single centre study of patients with metastatic colorectal cancer. We now report results with a further 56 patients treated at 14 centres. Low rates of grade 3 and 4 toxicity were seen, with no toxic deaths. Objective response rates were CR/PR=53%; NC=34.7%; PD=12.2%. Median time to progression was 8.3 months and overall survival was 14.5 months. This regimen is more convenient than those based around the conventional de Gramont regimen but is highly active and well tolerated; it forms part of a current UK MRC phase 3 trial.

Purpose: To assess the safety and toxicity profile of escalating doses of intravenous irinotecan, in combination with a fixed dose of oral ciclosporin (Cs) and to determine the pharmacokinetic profile of irinotecan and its metabolites. Patients and Methods: Patients with fluorouracil-refractory metastatic colorectal cancer received escalating doses of intravenous irinotecan from 40 to 125 mg/m2 every 2 weeks in combination with a fixed dose of oral Cs (5 mg/kg bid for 3 days). Pharmacokinetic analysis of plasma irinotecan and its metabolites SN38 and SN38G was performed during paired cycles with and without Cs. Results: Thirty-seven patients were treated. Dose-limiting toxicity of grade 4 neutropenia was seen at an irinotecan dose of 125 mg/m2. There was no grade 4 diarrhea, and only one patient experienced grade 3 diarrhea. Toxicities caused by Cs were generally mild. Pharmacokinetic studies demonstrated that irinotecan clearance was reduced from 13.4 to 5.8 L/h/m2 and area under the curve (AUC)0-tn was increased 2.2-fold by the coadministration of Cs. Similar significant increases in AUC0-24h were seen for both SN38 and SN38G (2.2-fold and 2.3-fold, respectively) in the presence of Cs. Antitumor activity was seen at every irinotecan dose level. Conclusion: The maximum tolerated irinotecan dose and recommended dose for phase II studies is 100 mg/m2 every 2 weeks. Dose-limiting diarrhea was not seen during this study, supporting the hypothesis that pharmacokinetic modulation of irinotecan by Cs may improve its therapeutic index. Further studies using this combination are warranted.

We investigated the activity of irinotecan given with a more convenient modified bimonthly de Gramont regimen of bolus and infusional 5-fluorouracil [IrMdG] in advanced or metastatic colorectal cancer in the first and second line setting. Irinotecan 180 mg m−2 was infused over 90 min. L-folinic acid 175 mg or d,l folinic acid 350 mg was given over 2 h followed by a bolus of 5-fluorouracil (400 mg m−2) and a 46 h continuous infusion of 5-fluorouracil (2.4–2.8 g m−2). Forty-six previously untreated patients (Group A) and 36 who had received 5-fluorouracil for metastatic disease (Group B) were recruited. Seventy-eight patients were evaluable for response. A partial response was seen in 13 out of 43 (30% [95%CI 28.1–31.9%]) in Group A and 8/35 (23% [95% CI 17.9–28.1%]) in Group B. 40% (95%CI 38.1–41.9%) of Group A and 26% (95% CI 20.9–31.1%) of Group B patients achieved disease stabilisation. The median progression free survival from the start of this treatment was 7 months (95% CI 4.4–9.6 months) in Group A and 5 months (95% CI 2.8–7.2 months) in Group B. Median overall survival was 14 months (95% CI 9.0–18.9) in Group A and 11 months (95% CI 5.9–16.1) in Group B. Grade 3–4 toxicity in both treatment groups were similar; leucopenia 17% and diarrhoea 7–8%. Grade 3–4 mucositis was not seen and severe alopecia affected only three patients. IrMdG is an active and well-tolerated regimen for both the first and second line treatment of advanced colorectal cancer. British Journal of Cancer (2002) 87, 1216–1220. doi:10.1038/sj.bjc.6600641 www.bjcancer.com © 2002 Cancer Research UK