Blarigan, Erin Van

3588 Background: Growing data suggest dietary factors are associated with survival among pts with non-metastatic CRC. However, data on diet and survival among pts with advanced or metastatic disease are very limited. Methods: We prospectively examined dietary fat intake assessed at initiation of treatment for advanced or metastatic CRC in relation to OS and PFS. This analysis was conducted among 1,149 pts in the CALGB 80405 randomized controlled trial who completed a validated food frequency questionnaire. We examined intakes of saturated, monounsaturated, and polyunsaturated (total n-3, long-chain n-3, and total n-6) fats as well as animal and vegetable fats. Based on data from non-metastatic CRC and other cancers, we hypothesized that higher intakes of long-chain n-3 fatty acids and vegetable fats would be associated with longer OS and PFS and higher intakes of saturated fat and animal fat would be associated with shorter OS and PFS. We used Cox proportional hazards regression to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI). Results: Over a median follow-up of 6.1 years [y; interquartile range (IQR): 5.3, 7.2 y], we observed 974 deaths and 103 events of progression without death during follow-up. Participants in this analysis had a median age of 59 y (IQR: 51 to 67 y); 41% were female and 86% identified as white. We observed no statistically significant associations between any type of dietary fat and OS. However, vegetable fat was non-linearly associated with longer PFS (HR comparing 4th to 1st quartile: 0.78; 95% CI: 0.64, 0.96; p-trend: 0.10). We also observed a linear association between continuous saturated fat and PFS (HR per 5% kcal/d: 1.21; 95% CI: 1.03, 1.42; p-value: 0.02), perhaps driven by pts with high saturated fat intake. Conclusions: We observed no statistically significant associations between types of dietary fat and OS among pts with advanced or metastatic CRC. However, a healthy diet that includes vegetable fat and is modest in saturated fat may be associated with longer PFS. Future studies to replicate these findings and examine diet in relation to cancer survival in racially/ethnically diverse populations are needed. Support: K07CA197077, U10CA180821, U10CA180882, https://acknowledgments.alliancefound.org . Clinical trial information: NCT00265850.

3568 Background: Diets inducing an elevated insulin response have been associated with increased recurrence and mortality in patients with non-metastatic colorectal cancer, but it remains unknown if postprandial hyperinsulinemia also affects progression and mortality in mCRC patients. The goal of this study was to assess the influence of dietary insulin load (DIL) and dietary insulin index (DII) on survival of mCRC patients. Methods: This was a prospective cohort study of 1,177 patients with previously untreated mCRC enrolled in a phase III trial of systemic chemotherapy plus biologics who reported dietary intake within one month after chemotherapy initiation. DIL was calculated as a function of food insulin index and the energy content of individual foods reported on a food frequency questionnaire. DII was calculated by dividing DIL by total energy intake. The primary endpoint was overall survival (OS). Secondary endpoints were progression-free survival (PFS) and treatment-related adverse events (TRAEs). The primary statistical test was a test for trend, which was performed using the median value for each quintile of dietary insulin score as a continuous variable. Cox proportional hazards regression was used to adjust for potential confounders including assigned treatment arm, known prognostic factors, comorbidities, body mass index, and physical activity. Results: Higher DIL was significantly associated with worse OS (ptrend = 0.04); patients in the highest quintile survived 34.1 months, compared to 27.7 months in the lowest quintile (Cox hazard ratio [HR] 1.22, 95% confidence interval [CI] 0.99 - 1.51). Higher DII was non-significantly associated with worse OS (HR 1.18, 95% CI 0.94 - 1.48, ptrend = 0.09). There was no significant association between dietary insulin scores and PFS. The influence of dietary insulin scores on survival did not differ significantly by various molecular markers involved in the insulin signaling pathway, including C-peptide, adiponectin, IGF-1, IGFBP-3, and IGFBP-7. Higher dietary insulin scores were significantly associated with greater risk of any TRAE. Those with a DIL greater than the median had a 75.4% rate of any TRAE, compared to 70.8% in those with a DIL less than or equal to the median (HR 1.19, 95% CI 1.03 - 1.38, p=0.02); the most significant associations were with neutropenia (HR 1.30, 95% CI 1.05 - 1.61, p=0.01) and diarrhea (HR 1.43, 95% CI 1.00 - 2.06, p=0.05). Conclusions: Higher DIL was significantly associated with worse OS, and both higher DIL and DII were significantly associated with increased TRAEs, in patients with previously untreated mCRC. These findings may inform future dietary recommendations for patients with mCRC. Further investigation into the molecular mechanisms underlying these associations is warranted. Clinical trial information: NCT00265850.

PURPOSERegular physical activity is associated with reduced risk of recurrence and mortality in patients with nonmetastatic colorectal cancer. Its influence on patients with advanced/metastatic colorectal cancer (mCRC) has been largely unexplored.PATIENTS AND METHODSWe conducted a prospective cohort study nested in Cancer and Leukemia Group B (Alliance)/SWOG 80405 (ClinicalTrials.gov identifier: NCT00265850 ), a National Cancer Institute–sponsored phase III trial of systemic therapy for mCRC. Within 1 month after therapy initiation, patients were invited to complete a validated questionnaire that reported average physical activity over the previous 2 months. On the basis of responses, we calculated metabolic equivalent task (MET) hours per week to quantify physical activity. The primary end point of the clinical trial and this companion study was overall survival (OS). Secondary end points included progression-free survival (PFS) and first grade 3 or greater treatment-related adverse events. To minimize confounding by poor and declining health, we excluded patients who experienced progression or died within 60 days of activity assessment and used Cox proportional hazards regression analysis to adjust for known prognostic factors, comorbidities, and weight loss.RESULTSThe final cohort included 1,218 patients. Compared with patients engaged in less than 3 MET hours per week of physical activity, patients engaged in 18 or more MET hours per week experienced an adjusted hazard ratio for OS of 0.85 (95% CI, 0.71 to 1.02; PTrend= .06) and for PFS of 0.83 (95% CI, 0.70 to 0.99; PTrend= .01). Compared with patients engaging in less than 9 MET hours per week, patients engaging in 9 or more MET hours per week experienced an adjusted hazard ratio for grade 3 or greater treatment-related adverse events of 0.73 (95% CI, 0.62 to 0.86; PTrend< .001).CONCLUSIONAmong patients with mCRC in Cancer and Leukemia Group B (Alliance)/SWOG 80405, association of physical activity with OS was not statistically significant. Greater physical activity was associated with longer PFS and lower adjusted risk for first grade 3 or greater treatment-related adverse events.

659 Background: Regular physical activity (PA) is associated with reduced risk of recurrence and mortality in non-metastatic colorectal cancer. Its influence on patients with metastatic colorectal cancer (mCRC) is largely unexplored. Methods: 1231 patients participating in CALGB 80405 (first-line phase III chemotherapy trial for mCRC) completed questionnaires that included self-report on PA at time of chemotherapy initiation and total metabolic equivalent task (MET)-hours/week were determined based on responses. The primary endpoint of the clinical trial and this companion study was overall survival (OS), with progression-free survival (PFS) as a secondary endpoint. To minimize confounding by poor and rapidly declining health, we excluded patients who experienced progression or died within 60 days of activity assessment and adjusted for known prognostic factors, comorbid illness, and weight loss over the previous six months. Results: Compared with patients engaged in less than three MET-hours/week of PA, patients engaged in 18 or more MET-hours/week experienced an adjusted hazard ratio for OS of 0.81 (95% CI 0.67 to 0.98, P for trend 0.03) and for PFS of 0.84 (95% CI 0.71 to 1.00, P for trend 0.03). Greater nonvigorous PA and walking duration were both associated with improved OS ( P for trend 0.01 and 0.04, respectively). Conclusions: In mCRC patients from CALGB 80405, greater total PA was associated with improved PFS and OS, while greater walking duration and non-vigorous PA were associated with reduced risk of all-cause mortality. Support: U10CA180821, U10CA180882. ClinicalTrials.gov ID: NCT00265850 [Table: see text]