Goldberg, Richard M

PURPOSE: In patients with stage III colon cancer (CC) whose tumors demonstrate microsatellite instability (MSI), the efficacy of adjuvant fluoropyrimidine (FP) with or without oxaliplatin has not been clearly demonstrated and the prognostic value of MSI remains uncertain. MATERIALS AND METHODS: Individual patient data from the ACCENT database were used to evaluate the effect of FP with or without oxaliplatin on disease-free survival (DFS) and overall survival (OS) among patients with MSI stage III CC and the prognostic value of MSI in patients treated with FP plus oxaliplatin, by stratified Cox models adjusted for demographic and clinicopathological factors. RESULTS: MSI status was available for 5,457 patients (609 MSI, 11.2%; 4848 microsatellite stable [MSS], 88.8%) from 12 randomized clinical trials (RCTs). Oxaliplatin significantly improved OS of MSI patients from the two RCTs testing FP with or without oxaliplatin (n = 185; adjusted hazard ratio [aHR] = 0.52, 95% CI, 0.28 to 0.93). Among the 4,250 patients treated with FP plus oxaliplatin (461 MSI and 3789 MSS), MSI was associated with better OS in the N1 group compared with MSS (aHR = 0.66; 95% CI, 0.46 to 0.95) but similar survival in the N2 population (aHR = 1.13; 95% CI, 0.86 to 1.48; P interaction = .029). The main independent prognosticators of MSI patients treated with FP plus oxaliplatin were T stage (aHR = 2.09; 95% CI, 1.29 to 3.38) and N stage (aHR = 3.57; 95% CI, 2.32 to 5.48). Similar results were observed for DFS in all analyses. CONCLUSION: Adding oxaliplatin to FP improves OS and DFS in patients with MSI stage III CC. Compared with MSS, MSI patients experienced better outcomes in the N1 group but similar survival in the N2 group.

Abstract Background: Cetuximab, an EGFR inhibitor used to treat multiple cancer types, including colon cancer, causes severe skin toxicity in 5%–20% of patients, leading to decreased quality of life and treatment delays. Our understanding of which patients have an increased risk of severe toxicities is limited. We conducted a genome-wide association study to identify germline variants predictive of cetuximab-induced severe skin toxicity. Methods: Our study included 1,209 patients with stage III colon cancer randomized to receive cetuximab plus 5-fluorouracil and oxaliplatin as part of the NCCTG N0147 (Alliance) clinical trial. Skin toxicity outcomes were collected using the Common Toxicity Criteria for Adverse Events version 3.0. We performed genotyping, evaluating approximately 10 million genetic variants. We used logistic regression to evaluate the association of each genetic variant and severe (grade ≥ 3) skin toxicity, adjusting for age, sex, and genetic ancestry. Genome-wide significance was defined as P < 5 × 10−8. Results: Participants were predominantly middle-aged white men; 20% (n = 243) experienced severe skin toxicity. Two genetic variants in the retinoic acid receptor alpha (RARA) gene were significantly associated with severe skin toxicity [OR, 3.93; 95% confidence interval (CI), 2.47–6.25; P < 7.8 × 10−9]. Functional annotations indicate these variants are in the RARA promoter. Additional significantly associated variants were identified in chromosome 2 intergenic regions. Conclusions: Identified variants could represent a potential target for risk stratification of patients with colon cancer receiving cetuximab. Impact: Retinoids have shown promise in the treatment of cetuximab-induced skin toxicity, so follow-up work could evaluate whether individuals with the RARA variant would benefit from retinoid therapy.

AbstractBackgroundEnergy balance-related biomarkers are associated with risk and prognosis of various malignancies. Their relationship to survival in metastatic colorectal cancer (mCRC) requires further study.MethodsBaseline plasma insulin-like growth factor (IGF)-1, IGF-binding protein (IGFBP)-3, IGFBP-7, C-peptide, and adiponectin were measured at time of trial registration in a prospective cohort of patients with mCRC participating in a National Cancer Institute–sponsored trial of first-line systemic therapy. We used Cox proportional hazards regression to adjust for confounders and examine associations of each biomarker with overall survival (OS) and progression-free survival (PFS). P values are 2-sided.ResultsMedian follow-up for 1086 patients was 6.2 years. Compared with patients in the lowest IGFBP-3 quintile, patients in the highest IGFBP-3 quintile experienced an adjusted hazard ratio (HR) for OS of 0.57 (95% confidence interval [CI] = 0.42 to 0.78; Pnonlinearity < .001) and for PFS of 0.61 (95% CI = 0.45 to 0.82; Ptrend = .003). Compared with patients in the lowest IGFBP-7 quintile, patients in the highest IGFBP-7 quintile experienced an adjusted hazard ratio for OS of 1.60 (95% CI = 1.30 to 1.97; Ptrend < .001) and for PFS of 1.38 (95% CI = 1.13 to 1.69; Ptrend < .001). Plasma C-peptide and IGF-1 were not associated with patient outcomes. Adiponectin was not associated with OS; there was a nonlinear U-shaped association between adiponectin and PFS (Pnonlinearity = .03).ConclusionsAmong patients with mCRC, high plasma IGFBP-3 and low IGFBP-7 were associated with longer OS and PFS. Extreme levels of adiponectin were associated with shorter PFS. These findings suggest potential avenues for prognostic and therapeutic innovation.

Abstract Background The American Joint Committee on Cancer staging and other prognostic tools fail to account for stage-independent variability in outcome. We developed a prognostic classifier adding Immunoscore to clinicopathological and molecular features in patients with stage III colon cancer. Methods Patient (n = 559) data from the FOLFOX arm of adjuvant trial NCCTG N0147 were used to construct Cox models for predicting disease-free survival (DFS). Variables included age, sex, T stage, positive lymph nodes (+LNs), N stage, performance status, histologic grade, sidedness, KRAS/BRAF, mismatch repair, and Immunoscore (CD3+, CD8+ T-cell densities). After determining optimal functional form (continuous or categorical) and within Cox models, backward selection was performed to analyze all variables as candidate predictors. All statistical tests were two-sided. Results Poorer DFS was found for tumors that were T4 vs T3 (hazard ratio [HR] = 1.76, 95% confidence interval [CI] = 1.19 to 2.60; P = .004), right- vs left-sided (HR = 1.52, 95% CI = 1.14 to 2.04; P = .005), BRAF V600E (HR = 1.74, 95% CI = 1.26 to 2.40; P < .001), mutant KRAS (HR = 1.66, 95% CI = 1.08 to 2.55; P = .02), and low vs high Immunoscore (HR = 1.69, 95% CI = 1.22 to 2.33; P = .001) (all P < .02). Increasing numbers of +LNs and lower continuous Immunoscore were associated with poorer DFS that achieved significance (both Ps< .0001). After number of +LNs, T stage, and BRAF/KRAS, Immunoscore was the most informative predictor of DFS shown multivariately. Among T1–3 N1 tumors, Immunoscore was the only variable associated with DFS that achieved statistical significance. A nomogram was generated to determine the likelihood of being recurrence-free at 3 years. Conclusions The Immunoscore can enhance the accuracy of survival prediction among patients with stage III colon cancer.

Abstract Background Diabetes is a prognostic factor for some malignancies, but its association with outcome in patients with advanced or metastatic colorectal cancer (CRC) is less clear. Methods This cohort study was nested within a randomized trial of first-line chemotherapy and bevacizumab and/or cetuximab for advanced or metastatic CRC. Patients were enrolled at 508 community and academic centers throughout the National Clinical Trials Network. The primary exposure was physician-documented diabetes at the time of enrollment. The primary endpoint was overall survival (OS); secondary endpoints were progression-free survival (PFS) and adverse events. Tests of statistical significance were two-sided. Results Among 2326 patients, 378 (16.3%) had diabetes. The median follow-up time was 6.0 years. We observed 1973 OS events and 2173 PFS events. The median time to an OS event was 22.7 months among those with diabetes and 27.1 months among those without diabetes (HR = 1.27, 95% CI = 1.13 to 1.44; P < .001). The median time to a PFS event was 9.7 months among those with diabetes and 10.8 months among those without diabetes (HR = 1.16, 95% CI = 1.03 to 1.30; P = .02). Patients with diabetes were more likely to experience no less than grade 3 hypertension (8.1% vs 4.4%; P = .054) but were not more likely to experience other adverse events, including neuropathy. Conclusions Diabetes is associated with an increased risk of mortality and tumor progression in patients with advanced or metastatic CRC. Patients with diabetes tolerate first-line treatment with chemotherapy and monoclonal antibodies similarly to patients without diabetes.