Abstract Background: Adhering to 2018 World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations is reportedly associated with better survival among long-term colon cancer survivors (likely affected by immortal time bias). Thus, it is important to validate survival benefits by assessing adherence shortly after diagnosis, and further investigation is needed to examine its association with chemotherapy outcomes. Methods: Using an NCI-sponsored adjuvant chemotherapy trial conducted in patients with stage III colon cancer (CALGB/SWOG 80702; NCT01150045), we included 1,666 patients who returned valid Willett food frequency questionnaires (FFQ) at chemotherapy initiation and derived WCRF/AICR scores accordingly (higher score suggesting higher adherence). The primary outcome was disease-free survival (time from FFQ completion to recurrence or death), and secondary outcomes were reduced relative dose intensity (RDI; <85% suggesting worse completion) and severe toxicities (grade ≥3 for any chemotherapy-related toxicity). To estimate the associations of WCRF/AICR scores (quartiles) with survival and chemotherapy outcomes, we conducted multivariable Cox proportional hazards regression for disease-free survival and multivariable logistic regression for reduced RDI and severe toxicities. Results: Compared to those in the lowest quartile of the WCRF/AICR score, patients in the highest quartile had significantly better disease-free survival (hazard ratio: 0.75 [0.58, 0.98], Ptrend = 0.02) and lower risk of reduced RDI (odds ratio [OR]: 0.74 [0.54, 1.00], Ptrend = 0.03), but not for severe toxicities (OR: 1.24 [0.93, 1.67], Ptrend = 0.11). Conclusions: In patients with stage III colon cancer, higher adherence to WCRF/AICR recommendations was associated with better survival and chemotherapy completion, but not for severe toxicities. Funding: https://acknowledgments.alliancefound.org Citation Format: En Cheng, Chao Ma, Qian Shi, Anthony F. Shields, Peter T. Campbell, Ardaman P. Shergill, Katherine A. Guthrie, Felix Couture, Philip Kuebler, Pankaj Kumar, Benjamin Tan, Smitha S. Krishnamurthi, Kimmie Ng, Eileen M. O'Reilly, Justin C. Brown, Philip A. Philip, Jeffrey A. Meyerhardt. Associations of WCRF/AICR recommendations with survival and chemotherapy outcomes in colon cancer: CALGB/SWOG 80702 (Alliance) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 5038.
Sex differences in chemotherapy completion, toxicities, and survival in colon cancer: an analysis of 2201 patients from CALGB/SWOG 80702 (Alliance)
Abstract Background Completing adjuvant chemotherapy and reducing toxicities are critical for maximizing survival after a colon cancer diagnosis. Sex, as a biological variable, may affect colon cancer chemotherapy completion, toxicities, and survival differently. Methods From a National Cancer Institute–sponsored trial conducted among patients with stage III colon cancer (Cancer and Leukemia Group B (Alliance)/Southwest Oncology Group 80702), we included 2201 patients receiving the standard adjuvant chemotherapy regimen of fluorouracil, leucovorin, and oxaliplatin. We calculated relative dose intensity to indicate chemotherapy completion and considered reduced relative dose intensity (values <85%) as a clinically significant deviation from standard fluorouracil, leucovorin, and oxaliplatin. Using National Cancer Institute’s Common Terminology Criteria for Adverse Events, we defined severe adverse events (grade ≥3) as the occurrence of any following event, including neutrophil count decrease, nausea, platelet count decrease, hypertension, peripheral neuropathy, diarrhea, fatigue, gastritis, creatinine level increase, gastric ulcer, myocardial ischemia, and cerebral ischemia. The primary survival outcome was disease-free survival (time from enrollment to colon cancer recurrence or death from any cause), and secondary survival outcomes were recurrence-free and overall survival. Results Compared with men, women were at statistically significantly higher risks of experiencing reduced relative dose intensity (adjusted odds ratio = 1.59, 95% CI = 1.29 to 1.96; P < .001) and severe advance events (adjusted odds ratio = 1.72, 95% CI = 1.41 to 2.11; P < .001). Yet, women had statistically significantly better disease-free survival (adjusted hazard ratio = 0.72, 95% CI = 0.59 to 0.87; P < .001) as well as better recurrence-free and overall survival. Conclusions Our findings suggested that women with colon cancer are more likely to have worse chemotherapy completion rates and more severe adverse events, but they have better survival. Sex as a biological variable warrants further consideration in chemotherapy administration and survivorship management after colon cancer diagnosis.
Sex differences in chemotherapy completion and adverse events among patients with colon cancer (CALGB/SWOG 80702) (Alliance).
3624 Background: Increasing chemotherapy completion and reducing chemotherapy adverse events (AE) are critical to improve survival after colon cancer diagnosis. Sex, as a biological variable, may impact chemotherapy treatment differently, and thus further investigation is needed to examine sex differences in chemotherapy completion and adverse events among patients with colon cancer. Methods: Among an NCI-sponsored trial conducted among patients with stage III colon cancer (CALGB/SWOG 80702), all patients received standard adjuvant chemotherapy FOLFOX (fluorouracil, leucovorin, and oxaliplatin). To signal chemotherapy completion, we utilized relative dose intensity (RDI) calculated as the ratio of the delivered dose intensity to planned dose intensity; and reduced RDI (RDI <85%) was considered as a clinically significant deviation from standard FOLFOX. From clinicians’ records of NCI’s Common Terminology Criteria for Adverse Events (CTCAE), we primarily focused on clinically significant AE such as neutrophils decrease, nausea, platelets decrease, hypertension, peripheral neuropathy, diarrhea, fatigue, gastritis, creatinine increase, gastric ulcer, myocardial ischemia, and cerebral ischemia; and severe AE was defined as the occurrence of any above AE with CTCAE grade ≥3. Using multivariable logistic regression that adjusted for body surface area (BSA) and other clinicopathological confounders, we estimated adjusted odds ratios (OR) for the associations of sex with reduced RDI and severe AE. Results: Of 2201 patients, mean (standard deviation [SD]) age was 60.9 (10.9) years, 1019 (46.3%) were female, 1750 (79.5%) were White, 172 (7.8%) were Hispanic, 964 (43.8%) experienced reduced RDI, and 1156 (52.5%) had severe adverse events. Compared to males, females were at significantly higher risks of experiencing reduced RDI (OR [95% CI]: 1.57 [1.27-1.93], P <0.001) and severe AE (OR [95% CI]: 1.73 [1.41-2.12], P <0.001). Conclusions: Our findings suggested females are more likely than men to experience reduced RDI and severe AE during colon cancer chemotherapy. Clinical Impact: In the era of precision medicine, sex (as a biological variable) should be considered in optimizing colon cancer chemotherapy to improve completion and reduce toxicities. Clinical trial information: NCT01150045 .
Plant-based diet and survival among patients with metastatic colorectal cancer
Abstract Background A plant-based diet is associated with better survival among patients with nonmetastatic colorectal cancer (CRC), but its association in metastatic CRC is unknown. Methods Using an National Cancer Institute–sponsored trial (CALGB/SWOG 80405), we included 1284 patients who completed validated food frequency questionnaires at the initiation of metastatic CRC treatment. We calculated 3 indices: overall plant-based diet index (PDI), which emphasized consumption of all plant foods while reducing animal food intake; healthful plant-based diet index (hPDI), which emphasized consumption of healthful plant foods such as whole grains, fruits, and vegetables; and unhealthful plant-based diet index (uPDI), which emphasized consumption of less healthful plant foods such as fruit juices, refined grains, and sugar-sweetened beverages. We estimated the associations of 3 indices (quintiles) with overall survival (OS) and progression-free survival (PFS) using multivariable Cox proportional hazards regression. Results We observed 1100 deaths and 1204 progression events (median follow-up = 6.1 years). Compared with the lowest quintile, patients in the highest quintile of PDI had significantly better survival (hazard ratio [HR] for OS = 0.76 [0.62-0.94], Ptrend = .004; PFS = 0.81 [0.66-0.99], Ptrend = .09). Similar findings were observed for hPDI (HR for OS = 0.81 [0.65-1.01], Ptrend = .053; PFS = 0.80 [0.65-0.98], Ptrend = .04), whereas uPDI was not associated with worse survival (HR for OS = 1.16 [0.94-1.43], Ptrend = .21; PFS = 1.12 [0.92-1.36], Ptrend = .42). Conclusions Our study suggests that a plant-based diet, especially when rich in healthful plant foods, is associated with better survival among patients with metastatic CRC. The cause of survival benefits warrants further investigation.
Plasma 25-Hydroxyvitamin D Levels and Survival in Stage III Colon Cancer: Findings from CALGB/SWOG 80702 (Alliance)
Abstract Purpose: To assess whether higher plasma 25-hydroxyvitamin D [25(OH)D] is associated with improved outcomes in colon cancer and whether circulating inflammatory cytokines mediate such association. Experimental Design: Plasma samples were collected from 1,437 patients with stage III colon cancer enrolled in a phase III randomized clinical trial (CALGB/SWOG 80702) from 2010 to 2015, who were followed until 2020. Cox regressions were used to examine associations between plasma 25(OH)D and disease-free survival (DFS), overall survival (OS), and time to recurrence (TTR). Mediation analysis was performed for circulating inflammatory biomarkers of C-reactive protein (CRP), IL6, and soluble TNF receptor 2 (sTNF-R2). Results: Vitamin D deficiency [25(OH)D <12 ng/mL] was present in 13% of total patients at baseline and in 32% of Black patients. Compared with deficiency, nondeficient vitamin D status (≥12 ng/mL) was significantly associated with improved DFS, OS, and TTR (all Plog-rank<0.05), with multivariable-adjusted HRs of 0.68 (95% confidence interval, 0.51–0.92) for DFS, 0.57 (0.40–0.80) for OS, and 0.71 (0.52–0.98) for TTR. A U-shaped dose–response pattern was observed for DFS and OS (both Pnonlinearity<0.05). The proportion of the association with survival that was mediated by sTNF-R2 was 10.6% (Pmediation = 0.04) for DFS and 11.8% (Pmediation = 0.05) for OS, whereas CRP and IL6 were not shown to be mediators. Plasma 25(OH)D was not associated with the occurrence of ≥ grade 2 adverse events. Conclusions: Nondeficient vitamin D is associated with improved outcomes in patients with stage III colon cancer, largely independent of circulation inflammations. A randomized trial is warranted to elucidate whether adjuvant vitamin D supplementation improves patient outcomes.
Association of Inflammatory Biomarkers With Survival Among Patients With Stage III Colon Cancer
ImportanceThe association of chronic inflammation with colorectal cancer recurrence and death is not well understood, and data from large well-designed prospective cohorts are limited.ObjectiveTo assess the associations of inflammatory biomarkers with survival among patients with stage III colon cancer.Design, Setting, and ParticipantsThis cohort study was derived from a National Cancer Institute–sponsored adjuvant chemotherapy trial Cancer and Leukemia Group B/Southwest Oncology Group 80702 (CALGB/SWOG 80702) conducted between June 22, 2010, and November 20, 2015, with follow-up ending on August 10, 2020. A total of 1494 patients with plasma samples available for inflammatory biomarker assays were included. Data were analyzed from July 29, 2021, to February 27, 2022.ExposuresPlasma inflammatory biomarkers (interleukin 6 [IL-6], soluble tumor necrosis factor α receptor 2 [sTNF-αR2], and high-sensitivity C-reactive protein [hsCRP]; quintiles) that were assayed 3 to 8 weeks after surgery but before chemotherapy randomization.Main Outcomes and MeasuresThe primary outcome was disease-free survival, defined as time from randomization to colon cancer recurrence or death from any cause. Secondary outcomes were recurrence-free survival and overall survival. Hazard ratios for the associations of inflammatory biomarkers and survival were estimated via Cox proportional hazards regression.ResultsOf 1494 patients (median follow-up, 5.9 years [IQR, 4.7-6.1 years]), the median age was 61.3 years (IQR, 54.0-68.8 years), 828 (55.4%) were male, and 327 recurrences, 244 deaths, and 387 events for disease-free survival were observed. Plasma samples were collected at a median of 6.9 weeks (IQR, 5.6-8.1 weeks) after surgery. The median plasma concentration was 3.8 pg/mL (IQR, 2.3-6.2 pg/mL) for IL-6, 2.9 × 103pg/mL (IQR, 2.3-3.6 × 103pg/mL) for sTNF-αR2, and 2.6 mg/L (IQR, 1.2-5.6 mg/L) for hsCRP. Compared with patients in the lowest quintile of inflammation, patients in the highest quintile of inflammation had a significantly increased risk of recurrence or death (adjusted hazard ratios for IL-6: 1.52 [95% CI, 1.07-2.14];P = .01 for trend; for sTNF-αR2: 1.77 [95% CI, 1.23-2.55];P &lt; .001 for trend; and for hsCRP: 1.65 [95% CI, 1.17-2.34];P = .006 for trend). Additionally, a significant interaction was not observed between inflammatory biomarkers and celecoxib intervention for disease-free survival. Similar results were observed for recurrence-free survival and overall survival.Conclusions and RelevanceThis cohort study found that higher inflammation after diagnosis was significantly associated with worse survival outcomes among patients with stage III colon cancer. This finding warrants further investigation to evaluate whether anti-inflammatory interventions may improve colon cancer outcomes.Trial RegistrationClinicalTrials.gov Identifier:NCT01150045
Diet- and Lifestyle‐Based Prediction Models to Estimate Cancer Recurrence and Death in Patients With Stage III Colon Cancer (CALGB 89803/Alliance)
PURPOSECurrent tools in predicting survival outcomes for patients with colon cancer predominantly rely on clinical and pathologic characteristics, but increasing evidence suggests that diet and lifestyle habits are associated with patient outcomes and should be considered to enhance model accuracy.METHODSUsing an adjuvant chemotherapy trial for stage III colon cancer (CALGB 89803), we developed prediction models of disease-free survival (DFS) and overall survival by additionally incorporating self-reported nine diet and lifestyle factors. Both models were assessed by multivariable Cox proportional hazards regression and externally validated using another trial for stage III colon cancer (CALGB/SWOG 80702), and visual nomograms of prediction models were constructed accordingly. We also proposed three hypothetical scenarios for patients with (1) good-risk, (2) average-risk, and (3) poor-risk clinical and pathologic features, and estimated their predictive survival by considering clinical and pathologic features with or without adding self-reported diet and lifestyle factors.RESULTSAmong 1,024 patients (median age 60.0 years, 43.8% female), we observed 394 DFS events and 311 deaths after median follow-up of 7.3 years. Adding self-reported diet and lifestyle factors to clinical and pathologic characteristics meaningfully improved performance of prediction models (c-index from 0.64 [95% CI, 0.62 to 0.67] to 0.69 [95% CI, 0.67 to 0.72] for DFS, and from 0.67 [95% CI, 0.64 to 0.70] to 0.71 [95% CI, 0.69 to 0.75] for overall survival). External validation also indicated good performance of discrimination and calibration. Adding most self-reported favorable diet and lifestyle exposures to multivariate modeling improved 5-year DFS of all patients and by 6.3% for good-risk, 21.4% for average-risk, and 42.6% for poor-risk clinical and pathologic features.CONCLUSIONDiet and lifestyle factors further inform current recurrence and survival prediction models for patients with stage III colon cancer.
The Diet of Higher Insulinemic Potential Is Not Associated with Worse Survival in Patients with Stage III Colon Cancer (Alliance)
Abstract Background: Hyperinsulinemia is considered to be important in the development of colon cancer, but few studies have investigated the associations of hyperinsulinemia with colon cancer survival via dietary scores. Methods: Empirical dietary index for hyperinsulinemia (EDIH) was derived to assess the insulinemic potential of daily diets reflecting the long-term insulin exposure, with higher (more positive) scores indicating higher insulinemic diets. We prospectively estimated the HRs and 95% confidence intervals (CI) to investigate the association of EDIH with disease-free, recurrence-free, and overall survival among patients with stage III colon cancer (1999–2009) enrolled in a randomized adjuvant chemotherapy trial (CALGB 89803). Results: Of 1,024 patients (median follow-up: 7.3 years), 311 died, 350 had recurrences, and 394 had events for disease-free survival. Compared with patients in the lowest quintile of EDIH, the corresponding HRs of patients in the highest quintile for disease-free survival events, cancer recurrence, and overall mortality were 0.80 (95% CI, 0.56–1.15), 0.76 (95% CI, 0.51–1.11), and 0.77 (95% CI, 0.52–1.14). Conclusions: Higher EDIH was not associated with the risk of colon cancer recurrence or mortality in this population of patients with stage III colon cancer. Impact: EDIH, as a measure of dietary insulinemic potential, may be associated with colon cancer risk but not survival in patients with late-stage colon cancer.