Marine ω-3 Polyunsaturated Fatty Acid and Fish Intake after Colon Cancer Diagnosis and Survival: CALGB 89803 (Alliance).

Background: Marine ω-3 polyunsaturated fatty acids (PUFAs), primarily found in dark fish, may prevent colorectal cancer progression, in part through inhibition of prostaglandin-endoperoxide synthase 2 (PTGS2). However, data in humans are limited.Methods: We examined marine ω-3 PUFAs and fish intake and survival among 1,011 colon cancer patients enrolled in Cancer and Leukemia Group B 89803 between 1999 and 2001 and followed through 2009. Diet was assessed during and 6 months after chemotherapy. We used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for disease-free (DFS), recurrence-free (RFS), and overall survival (OS).Results: We observed 343 recurrences and 305 deaths (median follow-up: 7 years). Patients in the highest vs. lowest quartile of marine ω-3 PUFA intake had an HR for DFS of 0.72 (95% CI, 0.54-0.97; Ptrend = 0.03). Individuals who consumed dark fish ≥1/week versus never had longer DFS (HR 0.65; 95% CI, 0.48-0.87; P-value = 0.007), RFS (HR 0.61; 95% CI, 0.46-0.86; Ptrend = 0.007), and OS (HR 0.68; 95% CI, 0.48-0.96; Ptrend = 0.04). In a subset of 510 patients, the association between marine ω-3 PUFA intake and DFS appeared stronger in patients with high PTGS2 expression (HR 0.32; 95% CI, 0.11-0.95; Ptrend = 0.01) compared with patients with absent/low PTGS2 expression (HR 0.78; 95% CI, 0.48-1.27; Ptrend = 0.35; Pinteraction = 0.19).Conclusions: Patients with high intake of marine ω-3 PUFAs and dark fish after colon cancer diagnosis may have longer DFS.Impact: Randomized controlled trials examining dark fish and/or marine ω-3 PUFA supplements and colon cancer recurrence/survival are needed. Cancer Epidemiol Biomarkers Prev; 27(4); 438-45. ©2018 AACR.

Coffee Intake, Recurrence, and Mortality in Stage III Colon Cancer: Results From CALGB 89803 (Alliance).

PURPOSE: Observational studies have demonstrated increased colon cancer recurrence in states of relative hyperinsulinemia, including sedentary lifestyle, obesity, and increased dietary glycemic load. Greater coffee consumption has been associated with decreased risk of type 2 diabetes and increased insulin sensitivity. The effect of coffee on colon cancer recurrence and survival is unknown. PATIENTS AND METHODS: During and 6 months after adjuvant chemotherapy, 953 patients with stage III colon cancer prospectively reported dietary intake of caffeinated coffee, decaffeinated coffee, and nonherbal tea, as well as 128 other items. We examined the influence of coffee, nonherbal tea, and caffeine on cancer recurrence and mortality using Cox proportional hazards regression. RESULTS: Patients consuming 4 cups/d or more of total coffee experienced an adjusted hazard ratio (HR) for colon cancer recurrence or mortality of 0.58 (95% CI, 0.34 to 0.99), compared with never drinkers (Ptrend = .002). Patients consuming 4 cups/d or more of caffeinated coffee experienced significantly reduced cancer recurrence or mortality risk compared with abstainers (HR, 0.48; 95% CI, 0.25 to 0.91; Ptrend = .002), and increasing caffeine intake also conferred a significant reduction in cancer recurrence or mortality (HR, 0.66 across extreme quintiles; 95% CI, 0.47 to 0.93; Ptrend = .006). Nonherbal tea and decaffeinated coffee were not associated with patient outcome. The association of total coffee intake with improved outcomes seemed consistent across other predictors of cancer recurrence and mortality. CONCLUSION: Higher coffee intake may be associated with significantly reduced cancer recurrence and death in patients with stage III colon cancer.

Aspirin and COX-2 inhibitor use in patients with stage III colon cancer.

We conducted a prospective, observational study of aspirin and COX-2 inhibitor use and survival in stage III colon cancer patients enrolled in an adjuvant chemotherapy trial. Among 799 eligible patients, aspirin use was associated with improved recurrence-free survival (RFS) (multivariable hazard ratio [HR] = 0.51, 95% confidence interval [CI] = 0.28 to 0.95), disease-free survival (DFS) (HR = 0.68, 95% CI = 0.42 to 1.11), and overall survival (OS) (HR = 0.63, 95% CI = 0.35 to 1.12). Adjusted HRs for DFS and OS censored at five years (in an attempt to minimize misclassification from noncancer death) were 0.61 (95% CI = 0.36 to 1.04) and 0.48 (95% CI = 0.23 to 0.99). Among 843 eligible patients, those who used COX-2 inhibitors had multivariable HRs for RFS, DFS, and OS of 0.53 (95% CI = 0.27 to 1.04), 0.60 (95% CI = 0.33 to 1.08), and 0.50 (95% CI = 0.23 to 1.07), and HRs of 0.47 (95% CI = 0.24 to 0.91) and 0.26 (95% CI = 0.08 to 0.81) for DFS and OS censored at five years. Aspirin and COX-2 inhibitor use may be associated with improved outcomes in stage III colon cancer patients.

Predictive and prognostic analysis of PIK3CA mutation in stage III colon cancer intergroup trial.

BACKGROUND: Somatic mutations in PIK3CA (phosphatidylinositol-4,5-bisphosphonate 3-kinase [PI3K], catalytic subunit alpha gene) activate the PI3K-AKT signaling pathway and contribute to pathogenesis of various malignancies, including colorectal cancer. METHODS: We examined associations of PIK3CA oncogene mutation with relapse, survival, and treatment efficacy in 627 stage III colon carcinoma case subjects within a randomized adjuvant chemotherapy trial (5-fluorouracil and leucovorin [FU/LV] vs irinotecan [CPT11], fluorouracil and leucovorin [IFL]; Cancer and Leukemia Group B 89803 [Alliance]). We detected PIK3CA mutation in exons 9 and 20 by polymerase chain reaction and pyrosequencing. Cox proportional hazards model was used to assess prognostic and predictive role of PIK3CA mutation, adjusting for clinical features and status of routine standard molecular pathology features, including KRAS and BRAF mutations and microsatellite instability (mismatch repair deficiency). All statistical tests were two-sided. RESULTS: Compared with PIK3CA wild-type cases, overall status of PIK3CA mutation positivity or the presence of PIK3CA mutation in either exon 9 or 20 alone was not statistically significantly associated with recurrence-free, disease-free, or overall survival (log-rank P > .70; P > .40 in multivariable regression models). There was no statistically significant interaction between PIK3CA and KRAS (or BRAF) mutation status in survival analysis (P(interaction) > .18). PIK3CA mutation status did not appear to predict better or worse response to IFL therapy compared with FU/LV therapy (P(interaction) > .16). CONCLUSIONS: Overall tumor PIK3CA mutation status is not associated with stage III colon cancer prognosis. PIK3CA mutation does not appear to serve as a predictive tumor molecular biomarker for response to irinotecan-based adjuvant chemotherapy.

Predictive and prognostic roles of BRAF mutation in stage III colon cancer: results from intergroup trial CALGB 89803.

PURPOSE: Alterations in the RAS-RAF-MAP2K (MEK)-MAPK signaling pathway are major drivers in colorectal carcinogenesis. In colorectal cancer, BRAF mutation is associated with microsatellite instability (MSI), and typically predicts inferior prognosis. We examined the effect of BRAF mutation on survival and treatment efficacy in patients with stage III colon cancer. METHODS: We assessed status of BRAF c.1799T>A (p.V600E) mutation and MSI in 506 stage III colon cancer patients enrolled in a randomized adjuvant chemotherapy trial [5-fluorouracil and leucovorin (FU/LV) vs. irinotecan (CPT11), FU and LV (IFL); CALGB 89803]. Cox proportional hazards model was used to assess the prognostic role of BRAF mutation, adjusting for clinical features, adjuvant chemotherapy arm, and MSI status. RESULTS: Compared with 431 BRAF wild-type patients, 75 BRAF-mutated patients experienced significantly worse overall survival [OS; log-rank P = 0.015; multivariate HR = 1.66; 95% CI: 1.05-2.63]. By assessing combined status of BRAF and MSI, it seemed that BRAF-mutated MSS (microsatellite stable) tumor was an unfavorable subtype, whereas BRAF wild-type MSI-high tumor was a favorable subtype, and BRAF-mutated MSI-high tumor and BRAF wild-type MSS tumor were intermediate subtypes. Among patients with BRAF-mutated tumors, a nonsignificant trend toward improved OS was observed for IFL versus FU/LV arm (multivariate HR = 0.52; 95% CI: 0.25-1.10). Among patients with BRAF wild-type cancer, IFL conferred no suggestion of benefit beyond FU/LV alone (multivariate HR = 1.02; 95% CI: 0.72-1.46). CONCLUSIONS: BRAF mutation is associated with inferior survival in stage III colon cancer. Additional studies are necessary to assess whether there is any predictive role of BRAF mutation for irinotecan-based therapy.

Multivitamin use is not associated with cancer recurrence or survival in patients with stage III colon cancer: findings from CALGB 89803.

PURPOSE: Multivitamin use is widespread in the United States, especially among patients with cancer. However, the influence of multivitamin supplementation on cancer recurrence and death after a curative resection of colon cancer is unknown. PATIENTS AND METHODS: We conducted a prospective, observational study of 1,038 patients with stage III colon cancer enrolled in a randomized adjuvant chemotherapy trial. Patients reported on multivitamin use during and 6 months after adjuvant chemotherapy. Patients were observed until March 2009 for disease recurrence and death. To minimize bias by occult recurrence, we excluded patients who recurred or died within 90 days of their multivitamin assessment. RESULTS: Among 1,038 patients, 518 (49.9%) reported multivitamin use during adjuvant chemotherapy. Compared with nonusers, the multivariate hazard ratio (HR) for disease-free survival was 0.94 (95% CI, 0.77 to 1.15) for patients who used multivitamins. Similarly, multivitamin use during adjuvant chemotherapy was not significantly associated with recurrence-free survival (multivariate HR, 0.93; 95% CI, 0.75 to 1.15) or overall survival (multivariate HR 0.92; 95% CI, 0.74 to 1.16). Multivitamin use reported 6 months after completion of adjuvant chemotherapy was also not associated with improved patient outcome, and consistent use both during and following adjuvant therapy conferred no benefit. Neither an increasing number of tablets nor increasing duration of use before cancer diagnosis was associated with cancer recurrence or mortality. Multivitamin use also did not improve the rates of grade 3 and higher GI toxicity. CONCLUSION: Multivitamin use during and after adjuvant chemotherapy was not significantly associated with improved outcomes in patients with stage III colon cancer.