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Molecular testing for genomic variants is recommended in advanced non-small cell lung cancer (NSCLC). Standard tissue biopsy is sometimes infeasible, procedurally risky, or insufficient in tumor tissue quantity. We present the analytical validation and concordance study of EGFR variants using a new 17-gene liquid biopsy assay (NCT02762877). Of 144 patients enrolled with newly diagnosed or progressive stage IV nonsquamous NSCLC, 140 (97%) had liquid assay results, and 117 (81%) had both EGFR blood and tissue results. Alterations were detected in 58% of liquid samples. Overall tissue-liquid concordance for EGFR alterations was 94.0% (95% CI 88.1%, 97.6%) with positive percent agreement of 76.7% (57.7%, 90.1%) and negative percent agreement of 100% (95.8%, 100%). Concordance for ALK structural variants was 95.7% (90.1%, 98.6%). This assay detected alterations in other therapeutically relevant genes at a rate similar to tissue analysis. These results demonstrate the analytical and clinical validity of this 17-gene assay.

Purpose Accurate assessments of recurrence risk and absolute treatment benefit are needed to inform colon cancer adjuvant therapy. The 12-gene Recurrence Score assay has been validated in patients with stage II colon cancer from the Cancer and Leukemia Group B 9581 and Quick and Simple and Reliable (QUASAR) trials. We conducted an independent, prospectively designed clinical validation study of Recurrence Score, with prespecified end points and analysis plan, in archival specimens from patients with stage II and III colon cancer randomly assigned to fluorouracil (FU) or FU plus oxaliplatin in National Surgical Adjuvant Breast and Bowel Project C-07. Methods Recurrence Score was assessed in 892 fixed, paraffin-embedded tumor specimens (randomly selected 50% of patients with tissue). Data were analyzed by Cox regression adjusting for stage and treatment. Results Continuous Recurrence Score predicted recurrence (hazard ratio for a 25-unit increase in score, 1.96; 95% CI, 1.50 to 2.55; P < .001), as well as disease-free and overall survival (both P < .001). Recurrence Score predicted recurrence risk (P = .001) after adjustment for stage, mismatch repair, nodes examined, grade, and treatment. Recurrence Score did not have significant interaction with stage (P = .90) or age (P = .76). Relative benefit of oxaliplatin was similar across the range of Recurrence Score (interaction P = .48); accordingly, absolute benefit of oxaliplatin increased with higher scores, most notably in patients with stage II and IIIA/B disease. Conclusion The 12-gene Recurrence Score predicts recurrence risk in stage II and stage III colon cancer and provides additional information beyond conventional clinical and pathologic factors. Incorporating Recurrence Score into the clinical context may better inform adjuvant therapy decisions in stage III as well as stage II colon cancer.

Purpose A greater understanding of the biology of tumor recurrence should improve adjuvant treatment decision making. We conducted a validation study of the 12-gene recurrence score (RS), a quantitative assay integrating stromal response and cell cycle gene expression, in tumor specimens from patients enrolled onto Cancer and Leukemia Group B (CALGB) 9581. Patients and Methods CALGB 9581 randomly assigned 1,713 patients with stage II colon cancer to treatment with edrecolomab or observation and found no survival difference. The analysis reported here included all patients with available tissue and recurrence (n = 162) and a random (approximately 1:3) selection of nonrecurring patients. RS was assessed in 690 formalin-fixed paraffin-embedded tumor samples with quantitative reverse transcriptase polymerase chain reaction by using prespecified genes and a previously validated algorithm. Association of RS and recurrence was analyzed by weighted Cox proportional hazards regression. Results Continuous RS was significantly associated with risk of recurrence (P = .013) as was mismatch repair (MMR) gene deficiency (P = .044). In multivariate analyses, RS was the strongest predictor of recurrence (P = .004), independent of T stage, MMR, number of nodes examined, grade, and lymphovascular invasion. In T3 MMR-intact (MMR-I) patients, prespecified low and high RS groups had average 5-year recurrence risks of 13% (95% CI, 10% to 16%) and 21% (95% CI, 16% to 26%), respectively. Conclusion The 12-gene RS predicts recurrence in stage II colon cancer in CALGB 9581. This is consistent with the importance of stromal response and cell cycle gene expression in colon tumor recurrence. RS appears to be most discerning for patients with T3 MMR-I tumors, although markers such as grade and lymphovascular invasion did not add value in this subset of patients.

Purpose We developed quantitative gene expression assays to assess recurrence risk and benefits from chemotherapy in patients with stage II colon cancer. Patients and Methods We sought validation by using RNA extracted from fixed paraffin-embedded primary colon tumor blocks from 1,436 patients with stage II colon cancer in the QUASAR (Quick and Simple and Reliable) study of adjuvant fluoropyrimidine chemotherapy versus surgery alone. A recurrence score (RS) and a treatment score (TS) were calculated from gene expression levels of 13 cancer-related genes (n = 7 recurrence genes and n = 6 treatment benefit genes) and from five reference genes with prespecified algorithms. Cox proportional hazards regression models and log-rank methods were used to analyze the relationship between the RS and risk of recurrence in patients treated with surgery alone and between TS and benefits of chemotherapy. Results Risk of recurrence was significantly associated with RS (hazard ratio [HR] per interquartile range, 1.38; 95% CI, 1.11 to 1.74; P = .004). Recurrence risks at 3 years were 12%, 18%, and 22% for predefined low, intermediate, and high recurrence risk groups, respectively. T stage (HR, 1.94; P < .001) and mismatch repair (MMR) status (HR, 0.31; P < .001) were the strongest histopathologic prognostic factors. The continuous RS was associated with risk of recurrence (P = .006) beyond these and other covariates. There was no trend for increased benefit from chemotherapy at higher TS (P = .95). Conclusion The continuous 12-gene RS has been validated in a prospective study for assessment of recurrence risk in patients with stage II colon cancer after surgery and provides prognostic value that complements T stage and MMR. The TS was not predictive of chemotherapy benefit.

Previously, we had identified gene expression patterns that predicted response to neoadjuvant docetaxel. Other studies have validated that a high Recurrence Score (RS) by the 21-gene RT-PCR assay is predictive of worse prognosis but better response to chemotherapy. We investigated whether tumor expression of these 21 genes and other candidate genes can predict response to docetaxel. Core biopsies from 97 patients were obtained before treatment with neoadjuvant docetaxel (4 cycles, 100 mg/m2 q3 weeks). Three 10-microm FFPE sections were submitted for quantitative RT-PCR assays of 192 genes that were selected from our previous work and the literature. Of the 97 patients, 81 (84%) had sufficient invasive cancer, 80 (82%) had sufficient RNA for QRTPCR assay, and 72 (74%) had clinical response data. Mean age was 48.5 years, and the median tumor size was 6 cm. Clinical complete responses (CR) were observed in 12 (17%), partial responses in 41 (57%), stable disease in 17 (24%), and progressive disease in 2 patients (3%). A significant relationship (P

The 12-gene Recurrence Score assay is a validated predictor of recurrence risk in stage II and III colon cancer patients. We conducted a prospectively designed study to validate this assay for prediction of recurrence risk in stage II and III rectal cancer patients from the Dutch Total Mesorectal Excision (TME) trial.RNA was extracted from fixed paraffin-embedded primary rectal tumor tissue from stage II and III patients randomized to TME surgery alone, without (neo)adjuvant treatment. Recurrence Score was assessed by quantitative real time-polymerase chain reaction using previously validated colon cancer genes and algorithm. Data were analysed by Cox proportional hazards regression, adjusting for stage and resection margin status. All statistical tests were two-sided.Recurrence Score predicted risk of recurrence (hazard ratio [HR] = 1.57, 95% confidence interval [CI] = 1.11 to 2.21, P = .01), risk of distant recurrence (HR = 1.50, 95% CI = 1.04 to 2.17, P = .03), and rectal cancer-specific survival (HR = 1.64, 95% CI = 1.15 to 2.34, P = .007). The effect of Recurrence Score was most prominent in stage II patients and attenuated with more advanced stage (P(interaction) ≤ .007 for each endpoint). In stage II, five-year cumulative incidence of recurrence ranged from 11.1% in the predefined low Recurrence Score group (48.5% of patients) to 43.3% in the high Recurrence Score group (23.1% of patients).The 12-gene Recurrence Score is a predictor of recurrence risk and cancer-specific survival in rectal cancer patients treated with surgery alone, suggesting a similar underlying biology in colon and rectal cancers.

Purpose These studies were conducted to determine the relationship between quantitative tumor gene expression and risk of cancer recurrence in patients with stage II or III colon cancer treated with surgery alone or surgery plus fluorouracil (FU) and leucovorin (LV) to develop multigene algorithms to quantify the risk of recurrence as well as the likelihood of differential treatment benefit of FU/LV adjuvant chemotherapy for individual patients. Patients and Methods We performed quantitative reverse transcription polymerase chain reaction (RT-qPCR) on RNA extracted from fixed, paraffin-embedded (FPE) tumor blocks from patients with stage II or III colon cancer who were treated with surgery alone (n = 270 from National Surgical Adjuvant Breast and Bowel Project [NSABP] C-01/C-02 and n = 765 from Cleveland Clinic [CC]) or surgery plus FU/LV (n = 308 from NSABP C-04 and n = 508 from NSABP C-06). Overall, 761 candidate genes were studied in C-01/C-02 and C-04, and a subset of 375 genes was studied in CC/C-06. Results A combined analysis of the four studies identified 48 genes significantly associated with risk of recurrence and 66 genes significantly associated with FU/LV benefit (with four genes in common). Seven recurrence-risk genes, six FU/LV-benefit genes, and five reference genes were selected, and algorithms were developed to identify groups of patients with low, intermediate, and high likelihood of recurrence and benefit from FU/LV. Conclusion RT-qPCR of FPE colon cancer tissue applied to four large independent populations has been used to develop multigene algorithms for estimating recurrence risk and benefit from FU/LV. These algorithms are being independently validated, and their clinical utility is being evaluated in the Quick and Simple and Reliable (QUASAR) study.

Noninvasive detection of urine tumor DNA (utDNA) has the potential to augment the diagnosis and management of bladder cancer. We sought to identify whether patient specific molecular events identified initially in the primary tumor could be detected in their utDNA. We interrogated both genetic and epigenetic events by a number of different technologies. Single nucleotide variants (SNVs) were analyzed by Next Generation Sequencing (NGS) on both the Ion Torrent platform (using amplicon enrichment) and the Illumina platform (via hybridization capture). Thirteen differentially methylated regions (DMRs) in the genome were analyzed by methylation-specific quantitative polymerase chain reaction (MS-qPCR). The cohort included patients with newly diagnosed NMIBC and those undergoing surveillance cystoscopy following a prior diagnosis of NMIBC. DNA was isolated from fixed paraffin embedded (FPE) primary tumors, matched blood buffy coat (BC), urine sediment (US) and, in some cases, clarified urine (CU-a.k.a. urine supernatant). Tumor specific molecular events were identified by comparing primary tumor tissue to BC (for SNVs with NGS) or to pooled data from urine DNA from healthy controls (for DMRs with MS-qPCR). Initially, 8 patients were evaluated with all three technologies. A larger cohort of 66 patients undergoing surveillance for NMIBC was then analyzed using MS-qPCR and a subset was also analyzed using NGS on the Ion Torrent platform. Tumor specific DMRs and/or SNVs were detected in tumor tissue from 73 of 74 patients. In the 8 patients assessed using both NGS platforms, SNVs were found in the primary tumor for 8/8 (Ion Torrent) and 6/8 (Illumina) patients, and both NGS platforms identified utDNA in 4 of 5 biopsy confirmed NMIBC patients. In patients with sufficient DNA to be assessed with all three technologies, in both US and CU, there was 100% agreement for all positive/negative calls for utDNA. Targeted genomic regions methylated in NMIBC tissue were seen to be methylated in the corresponding utDNA at the time of diagnosis or recurrence. In the cohort of 66 patients undergoing surveillance for NMIBC using MS-qPCR, a negative predictive value for high risk recurrences of 95% (with a prevalence of 10%) was achievable. These results provide evidence that both genetic and epigenetic events are evident in utDNA and reflect the presence and genetics of the NMIBC. This proof of concept study demonstrates the potential for a personalized non-invasive means to detect and monitor bladder cancer, thus making a valuable contribution to the field of precision medicine. Citation Format: Matthew J. Resnick, Margarita Lopatin, Neal D. Shore, Po N. Lam, Brian Helfand, Richard D. Abramson, Michael Crager, Michael Bonham, Haluk Tezcan, Kim M. Clark-Langone, Chris Silk, Seth Michelson, Gregory Alexander, Phillip G. Febbo. Analysis of tumor DNA in urine as a highly sensitive liquid biopsy for patients with non-muscle invasive bladder cancer (NMIBC). [abstract]. In: Proceedings of the AACR Precision Medicine Series: Integrating Clinical Genomics and Cancer Therapy; Jun 13-16, 2015; Salt Lake City, UT. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(1_Suppl):Abstract nr 14.

523 Background: The 12-gene colon cancer assay is the first commercially available molecular assay to predict the risk of recurrence in stage II/III colon and rectal cancer. Rigorous evidence for clinical validity and utility of an assay is imperative since the result is used for treatment decision-making. This summary outlines the studies that meet an established definition of clinical validation and additional studies that support the utility of the assay. Methods: Prospectively designed studies using archival tissue with pre-specified methods, clinical outcomes, and analysis plan were considered clinical validation studies (Simon et al. JNCI 2009). Additional studies that demonstrated the utility of the assay in a clinical setting were considered supportive. Results: The assay has been clinically validated in four independent studies with 3315 patients (2390 stage II/628 stage III colon and 130 stage II/167 stage III rectal). All four studies demonstrated a significant association (p

3512 Background: Standardized clinical tools which accurately quantify recurrence risk are needed for optimal adjuvant treatment of colon cancer. The 12-gene RS has been validated in stage II colon cancer pts from QUASAR and CALGB 9581. We conducted a large prospectively-designed clinical validation study of RS, w/ pre-specified endpoints, methods, and analysis plan, in stage II and III colon cancer pts randomized to FU or FU+Ox in NSABP C-07. Methods: 50% of C-07 pts w/ tissue were randomly selected, stratified on stage (AJCC 6th) and recurrence. Gene expression was quantitated by RT-PCR on 25 µm manually microdissected fixed colon tumor tissue. Data were analyzed by Cox regression controlling for stage and treatment (TRT). Results: RT-PCR was successful in 892/921 pts (97%): 449 FU, 443 FU + Ox; 264 st II, 409 st IIIA/B, 219 st IIIC. The primary endpoint was met: RS predicted recurrence (HR/25 units=1.96, 95% CI 1.50-2.55 p

3518 Background: The 12-gene RS (Genomic Health, Inc.) has been shown to predict risk of recurrence in stage II colon cancer (CC) pts in QUASAR. We conducted a validation study in tumor specimens f...

526 Background: High tumor grade is included in practice guidelines as a marker of higher recurrence risk in stage II colon cancer. Multiple systems for tumor grading exist, without a standardized approach. We characterize agreement of 2 methods for tumor grading and association with recurrence in the context of clinical, pathologic, and genomic tumor features including mismatch repair (MMR) and the 12-gene recurrence score (RS). Methods: Colon tumors were graded independently by 2 academic GI pathologists (P1, P2). Grade was defined by % tumor with gland-like structures: well (> 95%), moderately (50-95%) and poorly (< 50%) differentiated. P1 used this 3-tier system while P2 used 2-tier scheme with well and moderately differentiated tumors defined as low grade and poorly differentiated as high grade. All mucinous tumors were high-grade by P2 but not P1. Relationship to recurrence-free interval (RFI) was assessed by Cox regression. Results: Primary tumors from 504 stage II colon cancer treated with surgery alone were included. 18% (P1) and 31% (P2) were high grade. High grade tumors were more likely right-sided (≥ 60%) and MMR deficient (≥ 35%) for P1 and P2 (all p < 0.001). Proportion of mucinous tumors was similar for high and low grade by P1 (25% vs. 21%, p = 0.39). P2 high grade trended to lower recurrence (HR = 0.63, p = 0.10) while P1 grade was not associated w/ RFI (p = 0.46). In multivariate analyses including grade and RS, P2 high grade was associated with lower recurrence (p = 0.007) but P1 grade was not associated w/ RFI (p = 0.30). Neither grade was associated w/ RFI (p > 0.30) after controlling for RS, MMR, tumor location and mucinous histology. Using the two-tier scheme, agreement b/w the 2 pathologists was low (kappa = 0.30, 95% CI 0.21-0.39) in all pts and moderate if mucinous tumors were excluded (kappa = 0.52, 95% CI 0.40-0.64). Conclusions: High tumor grade was not found to be a marker of higher recurrence risk in stage II colon cancer. Other markers validated in stage II colon cancer, such as MMR and RS, should be considered. Interpathologist agreement on colon tumor grade is modest, even with central expert review. [Table: see text]

3503 Background: An understanding of biologic similarities and differences between st II and III colon cancer is needed to inform clinical practice and trial design. We compare pathologic markers a...

Background The Oncotype DX® Colon Cancer Assay is a new diagnostic test for determining the likelihood of recurrence in stage II colon cancer patients after surgical resection using fixed paraffin embedded (FPE) primary colon tumor tissue. Like the Oncotype DX Breast Cancer Assay, this is a high complexity, multi-analyte, reverse transcription (RT) polymerase chain reaction (PCR) assay that measures the expression levels of specific cancer-related genes. By capturing the biology underlying each patient's tumor, the Oncotype DX Colon Cancer Assay provides a Recurrence Score (RS) that reflects an individualized risk of disease recurrence. Here we describe its analytical performance using pre-determined performance criteria, which is a critical component of molecular diagnostic test validation. Results All analytical measurements met pre-specified performance criteria. PCR amplification efficiency for all 12 assays was high, ranging from 96% to 107%, while linearity was demonstrated over an 11 log2 concentration range for all assays. Based on estimated components of variance for FPE RNA pools, analytical reproducibility and precision demonstrated low SDs for individual genes (0.16 to 0.32 CTs), gene groups (≤0.05 normalized/aggregate CTs) and RS (≤1.38 RS units). Conclusions Analytical performance characteristics shown here for both individual genes and gene groups in the Oncotype DX Colon Cancer Assay demonstrate consistent translation of specific biology of individual tumors into clinically useful diagnostic information. The results of these studies illustrate how the analytical capability of the Oncotype DX Colon Cancer Assay has enabled clinical validation of a test to determine individualized recurrence risk after colon cancer surgery.