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Spot the differences between tumors: Immune checkpoint inhibitors, a form of cancer immunotherapy, have revolutionized cancer treatment in recent years, but unfortunately, not all tumors respond to these drugs. To gain insight into why some tumors might not respond, Zemek et al. compared gene expression patterns and cellular makeup of murine tumors that did or did not respond to immune checkpoint targeting. The authors then identified an immunotherapeutic combination that could be used to convert the microenvironment to a more favorable configuration in mice, suggesting that it may be possible to sensitize patients' tumors to immunotherapy by a similar approach. Cancer immunotherapy using antibodies that target immune checkpoints has delivered outstanding results. However, responses only occur in a subset of patients, and it is not fully understood what biological processes determine an effective outcome. This lack of understanding hinders the development of rational combination treatments. We set out to define the pretreatment microenvironment associated with an effective outcome by using the fact that inbred mouse strains bearing monoclonal cancer cell line–derived tumors respond in a dichotomous manner to immune checkpoint blockade (ICB). We compared the cellular composition and gene expression profiles of responsive and nonresponsive tumors from mice before ICB and validated the findings in cohorts of patients with cancer treated with ICB antibodies. We found that responsive tumors were characterized by an inflammatory gene expression signature consistent with up-regulation of signal transducer and activator of transcription 1 (STAT1) and Toll-like receptor 3 (TLR3) signaling and down-regulation of interleukin-10 (IL-10) signaling. In addition, responsive tumors had more infiltrating-activated natural killer (NK) cells, which were necessary for response. Pretreatment of mice with large established tumors using the STAT1-activating cytokine interferon-γ (IFNγ), the TLR3 ligand poly(I:C), and an anti–IL-10 antibody sensitized tumors to ICB by attracting IFNγ-producing NK cells into the tumor, resulting in increased cure rates. Our results identify a pretreatment tumor microenvironment that predicts response to ICB, which can be therapeutically attained. These data suggest a biomarker-driven approach to patient management to establish whether a patient would benefit from treatment with sensitizing therapeutics before ICB. [ABSTRACT FROM AUTHOR]

Background: We assessed the efficacy and safety of bevacizumab (BEV) through multiple lines in patients with recurrent glioblastoma who had progressed after first‐line treatment with radiotherapy, temozolomide, and BEV. Patients and Methods: TAMIGA (NCT01860638) was a phase II, randomized, double‐blind, placebo‐controlled, multicenter trial in adult patients with glioblastoma. Following surgery, patients with newly diagnosed glioblastoma received first‐line treatment consisting of radiotherapy plus temozolomide and BEV, followed by six cycles of temozolomide and BEV, then BEV monotherapy until disease progression (PD1). Randomization occurred at PD1 (second line), and patients received lomustine (CCNU) plus BEV (CCNU + BEV) or CCNU plus placebo (CCNU + placebo) until further disease progression (PD2). At PD2 (third line), patients continued BEV or placebo with chemotherapy (investigator's choice). The primary endpoint was survival from randomization. Secondary endpoints were progression‐free survival in the second and third lines (PFS2 and PFS3) and safety. Results: Of the 296 patients enrolled, 123 were randomized at PD1 (CCNU + BEV, n = 61; CCNU + placebo, n = 62). The study was terminated prematurely because of the high drop‐out rate during first‐line treatment, implying underpowered inferential testing. The proportion of patients receiving corticosteroids at randomization was similar (BEV 33%, placebo 31%). For the CCNU + BEV and CCNU + placebo groups, respectively, median survival from randomization was 6.4 versus 5.5 months (stratified hazard ratio [HR], 1.04; 95% confidence interval [CI], 0.69–1.59), median PFS2 was 2.3 versus 1.8 months (stratified HR, 0.70; 95% CI, 0.48–1.00), median PFS3 was 2.0 versus 2.2 months (stratified HR, 0.70; 95% CI, 0.37–1.33), and median time from randomization to a deterioration in health‐related quality of life was 1.4 versus 1.3 months (stratified HR, 0.76; 95% CI, 0.52–1.12). The incidence of treatment‐related grade 3 to 4 adverse events was 19% (CCNU + BEV) versus 15% (CCNU + placebo). Conclusion: There was no survival benefit and no detriment observed with continuing BEV through multiple lines in patients with recurrent glioblastoma. Implications for Practice: Previous research suggested that there may be value in continuing bevacizumab (BEV) beyond progression through multiple lines of therapy. No survival benefit was observed with the use of BEV through multiple lines in patients with glioblastoma who had progressed after first‐line treatment (radiotherapy + temozolomide + BEV). No new safety concerns arose from the use of BEV through multiple lines of therapy. This article focuses on the efficacy and safety of bevacizumab through multiple lines in patients with recurrent glioblastoma who progressed after first‐line treatment with radiotherapy, temozolomide, and bevacizumab. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Assessment of magnetic resonance imaging (MRI) in glioblastoma can be challenging. For patients with recurrent glioblastoma managed on the CABARET trial, we compared disease status assessed at hospitals and subsequent blinded central expert radiological review. Methods: MRI results and clinical status at specified time points were used for site and central assessment of disease status. Clinical status was determined by the site. Response Assessment in Neuro‐Oncology (RANO) criteria were used for both assessments. Site and central assessments of progression‐free survival (PFS) and response rates were compared. Inter‐rater variability for central review progression dates was assessed. Results: Central review resulted in shorter PFS in 45% of 89 evaluable patients (n = 40). Median PFS was 3.6 (central) versus 3.9 months (site) (hazard ratio 1.5, 95% confidence interval 1.3–1.8, P < 0.001). Responses were documented more frequently by sites (n = 16, 18%) than centrally (n = 11, 12%). Seven of 120 patients continued on trial without site‐determined progression for more than 6 months beyond the central review determination of progression. Of scans reviewed by all three central reviewers, 33% were fully concordant for progression date. Conclusion: While the difference between site and central PFS dates was statistically significant, the 0.3‐month median difference is small. The variability within central review is consistent with previous studies, highlighting the challenges in MRI interpretation in this context. A small proportion of patients benefited from treatment well beyond the centrally determined progression date, reinforcing that clinical status together with radiology results are important determinants of whether a therapy is effective for an individual. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the current study was to determine how carer needs changed longitudinally and understand associations between unmet needs and distress.Methods: Family carers of patients with high-grade glioma (HGG) were recruited. Carers completed questionnaires during patients' chemoradiotherapy (T1), 3 months (T2) and 6 months (T3) including the following: the Distress Thermometer, the General Health Questionnaire-12, the Partner and Carer Supportive Care (PCS) Needs Scale and its supplement the Access to Services Needs Scale and the Brain Tumour Specific Supportive Care Needs Scale. Linear latent growth models were applied.Results: The time 1 questionnaire was completed by 118 carers; 70 carers provided responses at time 3. While the mean numbers of elevated (moderate to high) needs remained stable over time, the specific needs changed. The most frequently reported PCS needs included the impact of caring on the carer's working life or usual activities, finding more accessible parking, making life decisions in the context of uncertainty, reducing stress in the patient's life and understanding the patient's experience. The most frequently reported need unique to carers of a brain tumour patient was for information on adjusting to cognitive changes in the patient. Other prominent needs included managing difficult aspects of the patient's behaviour and adjusting to changes in the patient's personality, both of which increased over time. Higher numbers of unmet needs were associated cross-sectionally with higher distress levels.Conclusion: Carers of people with HGG remain highly distressed and their needs evolve over time, indicating a requirement for ongoing evaluation of unmet needs and interventions to address carer psychological morbidities. [ABSTRACT FROM AUTHOR]

Purpose: To report the first comprehensive investigation of patient-reported cosmesis and breast-related quality of life (QOL) outcomes comparing patients randomized to risk-adapted single-dose intraoperative radiation therapy (TARGIT-IORT) versus external beam radiation therapy (EBRT) on the TARGIT-A trial.Methods and Materials: Longitudinal cosmesis and QOL data were collected from a subset of TARGIT-A participants who received TARGIT-IORT as a separate procedure (postpathology). Patients completed a cosmetic assessment before radiation therapy and annually thereafter for at least 5 years. Patients also completed the combined European Organization for Research and Treatment of Cancer (EORTC) core questionnaire and Breast-Specific Module in addition to the Body Image after Breast Cancer Questionnaire at baseline and annually thereafter. The combined EORTC questionnaires were also collected 3, 6, and 9 months after wide local excision.Results: An Excellent-Good cosmetic result was scored more often than a Fair-Poor result for both treatment groups across all time points. The TARGIT-IORT patients reported better breast-related QOL than EBRT patients. Statistically and clinically significant differences were seen at month 6 and year 1, with EBRT patients having moderately worse breast symptoms (a statistically significant difference of more than 10 in a 100-point scale) than TARGIT-IORT patients at these time points.Conclusion: Patients treated with TARGIT-IORT on the TARGIT-A trial have similar self-reported cosmetic outcome but better breast-related QOL outcomes than patients treated with EBRT. This important evidence can facilitate the treatment decision-making process for patients who have early breast cancer suitable for breast-conserving surgery and inform their clinicians. [ABSTRACT FROM AUTHOR]

Background & Aims: Although indirect methods of assessment of the exocrine pancreatic function have become the standard of care in the monitoring of pancreatic status, it still remains a current clinical challenge. Our aim was to compare the width of the pancreatic duct in pancreatic insufficient (PI) and pancreatic sufficient (PS) cystic fibrosis (CF) patients using secretin-enhanced magnetic resonance cholangiopancreatography (SE-MRCP). Methods: Thirty-seven CF patients were enrolled for this cross-sectional study, including 21 PI and 16 PS, all of whom underwent SE-MRCP. Measurement of the diameter of the pancreatic duct was performed in the head, body, and the tail of the pancreas at the baseline and after 1,2,3,5, and 10 minutes after secretin administration. Results: The diameter of the pancreatic duct in the head of the pancreas after 5 and 10 minutes of secretin injection was greater in PI than in PS patients (median = 2.0 mm [interquartile range: 1.6-3.0] vs. 2.0 mm [1.0-2.0] and 2.0 mm [1.4-2.0] vs 1.0 mm [1.0-2.0], p=0.047 and p=0.040, respectively). Areas under ROC curves for discriminating between PI and PS patients were 0.693 (95% Cl 0.521-0.866) and 0.698 (95% Cl 0.528-0.868), respectively. No other differences in the width of the duct were identified at the baseline or during SE-MRCP. Conclusions: The measurement of the diameter of the pancreatic duct during secretin stimulation does not allow for differentiating between PS and PI status in CF patients. [ABSTRACT FROM AUTHOR]

Background: Data from murine models suggest that CD40 activation may synergize with cytotoxic chemotherapy. We aimed to determine the maximum tolerated dose (MTD) and toxicity profile and to explore immunological biomarkers of the CD40-activating antibody CP-870,893 with cisplatin and pemetrexed in patients with malignant pleural mesothelioma (MPM). Patients and methods: Eligible patients had confirmed MPM, ECOG performance status 0-1, and measurable disease. Patients received cisplatin 75 mg/m² and pemetrexed 500 mg/m² on day 1 and CP-870,893 on day 8 of a 21-day cycle for maximum 6 cycles with up to 6 subsequent cycles single-agent CP-870,893. Immune cell subset changes were examined weekly by flow cytometry. Results: Fifteen patients were treated at three dose levels. The MTD of CP-870,893 was 0.15 mg/kg, and was exceeded at 0.2 mg/kg with one grade 4 splenic infarction and one grade 3 confusion and hyponatraemia. Cytokine release syndrome (CRS) occurred in most patients (80%) following CP-870,893. Haematological toxicities were consistent with cisplatin and pemetrexed chemotherapy. Six partial responses (40%) and 9 stable disease (53%) as best response were observed. The median overall survival was 16.5 months; the median progression-free survival was 6.3 months. Three patients survived beyond 30 months. CD19+ B cells decreased over 6 cycles of chemoimmunotherapy (P < 0.001) with a concomitant increase in the proportion of CD27+ memory B cells (P < 0.001) and activated CD86+CD27+ memory B cells (P<0.001), as an immunopharmacodynamic marker of CD40 activation. Conclusions: CP-870,893 with cisplatin and pemetrexed is safe and tolerable at 0.15 mg/kg, although most patients experience CRS. While objective response rates are similar to chemotherapy alone, three patients achieved long-term survival. Australia New Zealand Clinical Trials Registry number: ACTRN12609000294257. [ABSTRACT FROM AUTHOR]

Novel targeted therapies have found a niche in the treatment of many cancers, although the most responsive populations, best biomarkers of response, and appropriate treatment settings are still under investigation. With few exceptions, cancer vaccination strategies have not entered into routine management. In malignant mesothelioma, combination first-line chemotherapy with a platinum and pemetrexed remains the standard of care when systemic therapy is considered. Second-line chemotherapy is used but benefits are uncertain in the absence of appropriately controlled randomized trials. Currently, there are no novel targeted therapies or vaccinations that should be used in this disease outside the context of a clinical trial. [ABSTRACT FROM AUTHOR]

Whether the immune system can recognize malignant and premalignant cells and eliminate them to prevent the development of cancer is still a matter of open debate, but in our view, the balance of evidence favours this concept. Nonetheless, the International Agency for Research on Cancer has now predicted that cancer will overtake heart disease as the leading cause of death worldwide by 2010, showing that this protective mechanism often fails. Malignant mesothelioma has traditionally been considered a relatively non-immunogenic cancer. However, mesothelioma cells do express a set of well-defined tumour antigens that have been shown to engage with the host immune system. Mesothelioma should therefore be considered a target for immunotherapy. A variety of anticancer immunotherapies have been investigated in mesothelioma and in other malignancies, although these have been largely ineffective when used in isolation. Over recent years, there has been increasing interest in the possibility of combining immunotherapy with chemotherapy in the fight against cancer. Here, we discuss the rationale behind combining these two, long considered antagonistic, treatment options in the context of malignant mesothelioma. [ABSTRACT FROM AUTHOR]

Current interest in the MUC1/EMA mucin relates to its role in malignancy, and its potential as a therapeutic target. MUC1/EMA expression has been observed in the majority of epithelioid mesotheliomas. However, little is known of the characteristics of MUC1/EMA in mesothelioma. Herein, we studied the cell surface and soluble expression of the MUC1/EMA glycoprotein, and determined the mRNA and genomic expression profiles in mesothelioma. We found that the anti-MUC1 antibody, E29, was the most diagnostically useful of seven antibody clones examined with a sensitivity of 84% (16 out of 19 cases) and no false positive results. MUC1 mRNA expression was significantly higher in mesothelioma samples than in benign mesothelial cells. No amplification of the MUC1 gene was observed by FISH. Seven of 9 mesothelioma samples expressed MUC1-secreted mRNA isoform in addition to the archetypal MUC1/transmembrane form. CA15.3 (soluble MUC1) levels were significantly higher in the serum of mesothelioma patients than in healthy controls but were not significantly different to levels in patients with benign asbestos-related disease. CA15-3 in effusions could differentiate malignant from benign effusions but were not specific for mesothelioma. Thus, as in other cancers, alterations in MUC1 biology occur in mesothelioma and these results suggest that specific MUC1 characteristics may be useful for mesothelioma diagnosis and should also be investigated as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

The use of taxanes in early breast cancer is increasing. However, there are few mature studies of taxanes in this setting, and their role is uncertain. Our systematic review of randomised trials of adjuvant or neoadjuvant systemic therapy identified ten reported trials comparing a taxane-containing group with a non-taxane-containing control group in women with early breast cancer. Four of five neoadjuvant trials showed higher rates of complete response with taxanes, although differences were not significant. All five adjuvant trials showed improvements in disease-free survival with taxanes, and these improvements were significant in three trials and independent of oestrogen-receptor status. Two trials showed a significant improvement in overall survival. These results support the use of adjuvant taxanes in women with early breast cancer and involved lymph nodes. Longer follow-up of these trials and results from continuing trials are needed to clarify the best use of taxanes in early breast cancer. [Copyright &y& Elsevier]

The glucocorticoid (GC) steroid dexamethasone (Dex) is used as a supportive care co-medication for cancer patients undergoing standard care pemetrexed/platinum doublet chemotherapy. As trials for new cancer immunotherapy treatments increase in prevalence, it is important to track the immunological changes induced by co-medications commonly used in the clinic, but not specifically included in trial design or in pre-clinical models. Here, we document a number of Dex -induced immunological effects, including a large-scale lymphodepletive effect particularly affecting CD4+T cells but also CD8+T cells. The proportion of regulatory T cells within the CD4+compartment did not change after Dex was administered, however a significant increase in proliferation and activation of regulatory T cells was observed. We also noted Dex -induced proportional changes in dendritic cell (DC) subtypes. We discuss these immunological effects in the context of chemoimmunotherapy strategies, and suggest a number of considerations to be taken into account when designing future studies where Dex and other GCs may be in use. [ABSTRACT FROM PUBLISHER]

Imaging of malignant pleural mesothelioma is essential to patient management, prognostication, and response assessment. From animal models to clinical trials, the gamut of research activities and clinical standards relies on imaging to provide information on lesion morphology and the growing number of physiologic characteristics amenable to capture through imaging techniques. The complex morphology, growth pattern, and biological mechanisms of mesothelioma, however, present challenges for image acquisition and interpretation. Nevertheless, novel approaches to image acquisition and subsequent image analysis have expanded the opportunities for (as well as the need for) imaging in this disease. This paper summarizes the imaging-based research presented orally at the 2014 International Conference of the International Mesothelioma Interest Group (iMig) in Cape Town, South Africa, October 2014. Presented topics include the imaging of hypoxia in a murine model through positron emission tomography (PET), the use of diffusion-weighted magnetic resonance imaging (MRI) to assess the histologic composition of biphasic mesothelioma and to assess early response to chemotherapy, the correlation of CT-based tumor volume with the volume of the post-surgical tumor specimen, the development of volumetric tumor response criteria, and pre-treatment tumor volume growth considerations for tumor response assessment. [ABSTRACT FROM AUTHOR]

Background: New therapeutic strategies for malignant mesothelioma are urgently needed. In the DETERMINE study, we investigated the effects of the cytotoxic-T-lymphocyte-associated antigen 4 (CTLA-4) monoclonal antibody tremelimumab in patients with previously treated advanced malignant mesothelioma.Methods: DETERMINE was a double-blind, placebo-controlled, phase 2b trial done at 105 study centres across 19 countries in patients with unresectable pleural or peritoneal malignant mesothelioma who had progressed after one or two previous systemic treatments for advanced disease. Eligible patients were aged 18 years or older with Eastern Cooperative Oncology Group performance status of 0 or 1 and measurable disease as defined in the modified Response Evaluation Criteria In Solid Tumors (RECIST) version 1.0 for pleural mesothelioma or RECIST version 1.1 for peritoneal mesothelioma. Patients were randomly assigned (2:1) in blocks of three, stratified by European Organisation for Research and Treatment of Cancer status (low risk vs high risk), line of therapy (second line vs third line), and anatomic site (pleural vs peritoneal), by use of an interactive voice or web system, to receive intravenous tremelimumab (10 mg/kg) or placebo every 4 weeks for 7 doses and every 12 weeks thereafter until a treatment discontinuation criterion was met. The primary endpoint was overall survival in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of study drug. The trial is ongoing but no longer recruiting participants, and is registered with ClinicalTrials.gov, number NCT01843374.Findings: Between May 17, 2013, and Dec 4, 2014, 571 patients were randomly assigned to receive tremelimumab (n=382) or placebo (n=189), of whom 569 patients received treatment (two patients in the tremelimumab group were excluded from the safety population because they did not receive treatment). At the data cutoff date (Jan 24, 2016), 307 (80%) of 382 patients had died in the tremelimumab group and 154 (81%) of 189 patients had died in the placebo group. Median overall survival in the intention-to-treat population did not differ between the treatment groups: 7·7 months (95% CI 6·8-8·9) in the tremelimumab group and 7·3 months (5·9-8·7) in the placebo group (hazard ratio 0·92 [95% CI 0·76-1·12], p=0·41). Treatment-emergent adverse events of grade 3 or worse occurred in 246 (65%) of 380 patients in the tremelimumab group and 91 (48%) of 189 patients in the placebo group; the most common were dyspnoea (34 [9%] patients in the tremelimumab group vs 27 [14%] patients in the placebo group), diarrhoea (58 [15%] vs one [<1%]), and colitis (26 [7%] vs none). The most common serious adverse events were diarrhoea (69 [18%] patients in the tremelimumab group vs one [<1%] patient in the placebo group), dyspnoea (29 [8%] vs 24 [13%]), and colitis (24 [6%] vs none). Treatment-emergent events leading to death occurred in 36 (9%) of 380 patients in the tremelimumab group and 12 (6%) of 189 in the placebo group; those leading to the death of more than one patient were mesothelioma (three [1%] patients in the tremelimumab group vs two [1%] in the placebo group), dyspnoea (three [1%] vs two [1%]); respiratory failure (one [<1%] vs three [2%]), myocardial infarction (three [1%] vs none), lung infection (three [1%] patients vs none), cardiac failure (one [<1%] vs one [<1%]), and colitis (two [<1%] vs none). Treatment-related adverse events leading to death occurred in five (1%) patients in the tremelimumab group and none in the placebo group. The causes of death were lung infection in one patient, intestinal perforation and small intestinal obstruction in one patient; colitis in two patients, and neuritis and skin ulcer in one patient.Interpretation: Tremelimumab did not significantly prolong overall survival compared with placebo in patients with previously treated malignant mesothelioma. The safety profile of tremelimumab was consistent with the known safety profile of CTLA-4 inhibitors. Investigations into whether immunotherapy combination regimens can provide greater efficacy than monotherapies in malignant mesothelioma are ongoing.Funding: AstraZeneca. [ABSTRACT FROM AUTHOR]

Imaging plays an important role in the detection, diagnosis, staging, response assessment, and surveillance of malignant pleural mesothelioma. The etiology, biology, and growth pattern of mesothelioma present unique challenges for each modality used to capture various aspects of this disease. Clinical implementation of imaging techniques and information derived from images continue to evolve based on active research in this field worldwide. This paper summarizes the imaging-based research presented orally at the 2016 International Conference of the International Mesothelioma Interest Group (iMig) in Birmingham, United Kingdom, held May 1–4, 2016. Presented topics included intraoperative near-infrared imaging of mesothelioma to aid the assessment of resection completeness, an evaluation of tumor enhancement improvement with increased time delay between contrast injection and image acquisition in standard clinical magnetic resonance imaging (MRI) scans, the potential of early contrast enhancement analysis to provide MRI with a role in mesothelioma detection, the differentiation of short- and long-term survivors based on MRI tumor volume and histogram analysis, the response-assessment potential of hemodynamic parameters derived from dynamic contrast-enhanced computed tomography (DCE-CT) scans, the correlation of CT-based tumor volume with post-surgical tumor specimen weight, and consideration of the need to update the mesothelioma tumor response assessment paradigm. [ABSTRACT FROM AUTHOR]

Objectives The immune effects of EGFR tyrosine kinase inhibitors (EGFR-TKIs) are poorly understood. Identifying immune biomarkers could guide patient selection and optimisation of EGFR-TKI-immunotherapy combinations. Materials and methods 33 patients with NSCLC treated with an EGFR-TKI were prospectively enrolled. Peripheral blood mononuclear cells were collected pre-treatment, and after 1, 3 and 8 weeks. Flow cytometry was used to identify immune cell subsets, including PD-1 and PD-L1 expressing T cells. Immune parameters were correlated with clinical outcomes. Results Compared to healthy donors ( n = 10), patients had higher pre-treatment proportions of proliferating and PD-L1 + CD3 + T cells ( p < 0.001). Compared to patients with an EGFR mutation ( n = 12), patients without a known mutation ( n = 21) had higher proportions of proliferating CD4 + and PD-L1 + CD3 + T cells ( p = 0.03). There was a significant increase in PD-L1 + T cells after 1 week of EGFR-TKI in patients whose disease progressed compared to non-progressors. Patients with higher PD-L1 + CD3 + T cells at 1-week were more likely to progress (OR 30.3, p < 0.01) and had shorter PFS (1.6 vs. 8.8 m; p < 0.01) and OS (3.8 vs 23.2 m; p < 0.001) than those with fewer PD-L1 + CD3 + T cells. On multivariate analysis, high PD-L1 + CD3 + T cells was the only independent predictor for PFS (HR 3.7, p = 0.01), while for OS independent predictors were high PD-L1 + CD3 + T cells (HR 6.5, p < 0.01) and EGFR-negative status (HR 3.3, p = 0.04). Conclusions There was a significant correlation between PD-L1 expression on peripheral T cells and clinical outcomes in EGFR-TKI-treated NSCLC. This warrants further validation as a blood-based biomarker that may identify candidates for PD-1 inhibitors or immunotherapy-EGFR-TKI combinations. [ABSTRACT FROM AUTHOR]

Objectives Malignant pleural mesothelioma (MPM) is a chemotherapy resistant tumor with a poor prognosis. Hypoxia is increasingly recognized as an important factor in tumor aggressiveness and cellular resistance to chemotherapy and radiation treatment. This prospective pilot study was performed with [F-18] fluoromisonidazole (FMISO) PET-CT to characterize hypoxia in patients with MPM. Materials and methods Twenty prospectively recruited patients with histologically or cytologically confirmed MPM not currently receiving systemic or local treatment underwent both FMISO and fluorodeoxyglucose (FDG) PET-CT scans within 2 weeks. FMISO and FDG PET-CT scans were independently analyzed visually and semi-quantitatively using SUVmax and tumor to background ratio (TBR) in order to assess tumor hypoxia and metabolic activity. Lesion by lesion analysis was performed in sites of measurable pleural masses. Results Visual analysis demonstrated tumor FMISO activity in 17 of 20 patients, and tumor FDG activity in 19 of 20 patients. Focal areas of bulky tumor were most likely to demonstrate hypoxia. In 19 patients suitable for semi-quantitative analysis the median FDG SUVmax was 6.4 (range 1.9–19.1), median FMISO SUVmax was 2.5 (range 1.4–3.7) and median FMISO TBR was 1.8 (1.1–2.5). There was a positive correlation between intensity of metabolic activity and hypoxia ( r = 0.72, p = 0.001). Lesion by lesion analysis demonstrated a positive correlation between tumor thickness and FMISO activity ( r = 0.77, p < 0.001). Conclusion This pilot study confirms that MPM is a tumor with significant areas of hypoxia, particularly in dominant tumor masses. The relationship of tumor hypoxia to effectiveness of chemotherapy and/or radiation therapy warrants prospective assessment. [ABSTRACT FROM AUTHOR]

Objectives Non-steroidal anti-inflammatory drugs (NSAIDs) and COX-2 inhibitors have been associated with lower incidence rates of some cancers. Because asbestos can cause chronic inflammation at the pleural and peritoneal surfaces we hypothesised that NSAID and COX-2 inhibitors would inhibit the development of asbestos-induced mesothelioma. Materials and methods A murine model of asbestos-induced mesothelioma was used to test this hypothesis by providing the NSAID, aspirin, daily in the feed at 50 mg/kg or 250 mg/kg. In a parallel study, the relationship between the use of NSAID and COX-2 inhibitors and mesothelioma was investigated in a human cohort of 1738 asbestos exposed people living or working in Wittenoom, Western Australia (a crocidolite mine site). Results Aspirin did not alter the rate of disease development or increase the length of time that mice survived. Aspirin had a small but significant effect on disease latency (the time between asbestos exposure and first evidence of disease; p < 0.05) but disease progression was not affected by the continued presence of the drug. In the Wittenoom cohort, individuals who reported use of NSAIDs, COX-2 inhibitors or both did not have a lower incidence of mesothelioma (HR = 0.85; 95% CI = 0.53–1.37, p = 0.50), (HR = 0.69; 95% CI = 0.21–2.30, p = 0.55) and (HR = 0.43; 95% CI = 0.16–1.13, p = 0.087) respectively. Conclusion We conclude that NSAIDs and COX-2 inhibitors do not moderate mesothelioma development or progression in a human cohort exposed to asbestos and this result is confirmed in an autochthonous mouse model. [ABSTRACT FROM AUTHOR]