Kahlenberg, Morton S.

3516 Background: Epidemiological data suggest a protective effect of vitamin D on CC risk. However, association of serum vitamin D level with clinical outcome in pts with surgically resected CC remains unknown. We analyzed total circulating 25-hydroxyvitamin D [25(OH)D)] with clinical outcome in pts with resected stage III CC treated with FOLFOX +/- cetuximab in a phase III trial. Methods: Association of pre-treatment level of plasma 25(OH)D with disease-free survival (DFS) and time-to-recurrence (TTR) was analyzed with 25(OH)D as a continuous variable by a relative risk model with splines and as a binary variable (vitamin D deficient [<30 ng/mL]) using multivariable Cox regression. Results: Overall, 49% (291/600) of pts were vitamin D deficient. Prevalence of vitamin D deficiency was significantly higher in women vs men (52% vs. 48%, p=0.030) and in blacks vs whites (74% vs. 45%, p=0.0003). The continuous 25(OH)D level and pt sex were associated by the interaction test (pinteraction=0.044). There were no statistically significant associations with DFS/TTR for either continuous 25(OH)D level (DFS, p=0.22; TTR, p=0.26) nor for vitamin D deficiency (DFS, adjusted hazard ratio [HRadj]=1.01, 95% CI, 0.74-1.38; padj=0.94; TTR, HRadj=1.00; CI, 0.72-1.38; padj=0.99. A comparison of the highest vs lowest tertile showed a significant association between the highest 25(OH)D level and better outcomes in men (DFS, HRadj.=0.18, CI, 0.04-0.76, padj=0.020; TTR, HRadj.=0.12, CI, 0.02-0.64, padj=0.014), but not in women (DFS, pinteraction=0.039; TTR, pinteraction=0.033). Conclusions: Nearly one-half of pts in the clinical trial cohort were vitamin D deficient with lowest 25(OH)D levels found in women and blacks. While vitamin D deficiency was not associated with adverse outcome, high levels of vitamin D in men, but not women, were associated with longer survival. Support: U10CA180821, U10CA180882, U10CA180820, U10CA180863, U10CA180888, U10CA077202, CCSRI 021039. ClinicalTrials.gov Identifier: NCT00079274.

CRA3507 Background: FOLFOX is standard adjuvant therapy for stage III CC. Adding Cmab to FOLFOX benefits pts with metastatic CC WT KRAS tumors. N0147 assessed the potential benefit of Cmab added to FOLFOX. Methods: 21-56 days following resection and informed consent, KRAS status was centrally determined. Pts with wtKRAS CC were randomized to 12 biweekly cycles of oxaliplatin 85 mg/m2 d1, with leucovorin 400 mg/m2, 5FU 400 mg/m2 bolus IV, then 46-hr IV 5FU 2,400 mg/m2 on d1-2 (mFOLFOX6), without (arm A) or with Cmab (arm D) 250 mg/m2 d1&8, with Cmab at 400 mg/m2, cycle 1, d1. Primary endpoint was 3-yr disease free survival (DFS). Secondary endpoints included overall survival (OS) and toxicity. Planned accrual of 2,070 wtKRAS pts provided 90% power to detect hazard ratio (HR) of 1.33 with 2-sided α=0.05; with interim analyses after 25%, 50%, and 75% of planned events. Results: 1,760 wtKRAS pts (Arm A-858, Arm D-902) were enrolled at the time of closure; median follow-up on 1,624 pts is 15.9 months. Trial closed to accrual when preplanned interim analysis after 50% of planned events demonstrated no benefit to addition of Cmab. 3-yr DFS favored FOLFOX alone (HR 1.18, 95% CI 0.92-1.52; p=0.33). No benefit of Cmab was observed in any subgroups assessed. Any grade ≥ 3 AE, diarrhea, and failure to complete 12 cycles was significantly increased in arm D. Increased toxicity and greater differences in all outcomes were observed in pts aged ≥ 70 ( Table ). Conclusions: In this randomized phase III trial the addition of Cmab to mFOLFOX6 was of no benefit for pts with resected stage III wtKRAS CC. Supported by NIH Grant CA25224, Bristol-Myers Squibb, ImClone, Sanofi-Aventis, and Pfizer. [Table: see text] [Table: see text]

AbstractBackground.Preclinical and epidemiological data suggest that metformin might have antineoplastic properties against colon cancer (CC). However, the effect of metformin use on patient survival in stage III CC after curative resection is unknown. The survival outcomes were comparable regardless of the duration of metformin use.Patients and Methods.Before randomization to FOLFOX (folinic acid, 5-fluorouracil, oxaliplatin) with or without cetuximab, 1,958 patients with stage III CC enrolled in the N0147 study completed a questionnaire with information on diabetes mellitus (DM) and metformin use. Cox models were used to assess the association between metformin use and disease-free survival (DFS), overall survival (OS), and the time to recurrence (TTR), adjusting for clinical and/or pathological factors.Results.Of the 1,958 patients, 1,691 (86%) reported no history of DM, 115 reported DM with metformin use (6%), and 152 reported DM without metformin use (8%). The adjuvant treatment arms were pooled, because metformin use showed homogeneous effects on outcomes across the two arms. Among the patients with DM (n = 267), DFS (adjusted hazard ratio [aHR], 0.90; 95% confidence interval [CI], 0.59–1.35; p = .60), OS (aHR, 0.99; 95% CI, 0.65–1.49; p = .95), and TTR (aHR, 0.87; 95% CI, 0.56–1.35; p = .53) were not different for the metformin users compared with the nonusers after adjusting for tumor and patient factors. The survival outcomes were comparable regardless of the duration of metformin use (&lt;1, 1–5, 6–10, ≥11 years) before randomization (ptrend = .64 for DFS, ptrend = .84 for OS, and ptrend = .87 for TTR). No interaction effects were observed between metformin use and KRAS, BRAF mutation status, tumor site, T/N stage, gender, or age.Conclusions.Patients with stage III CC undergoing adjuvant chemotherapy who used metformin before the diagnosis of CC experienced DFS, OS, and TTR similar to those for non-DM patients and DM patients without metformin use.

Alcohol consumption is associated with a modest increased risk of colon cancer, but its relationship with colon cancer survival has not been elucidated. Using data from a phase III randomized adjuvant trial, we assessed the association of alcohol consumption with colon cancer outcomes. Patients completed a risk factor questionnaire before randomization to FOLFOX or FOLFOX + cetuximab (N = 1984). Information was collected on lifestyle factors, including smoking, physical activity and consumption of different types of alcohol. Cox models assessed the association between alcohol consumption and outcomes of disease‐free survival (DFS), time‐to‐recurrence (TTR) and overall survival (OS), adjusting for age, sex, study arm, body mass, smoking, physical activity and performance status. No statistically significant difference in outcomes between ever and never drinkers were noted [hazard ratio (HR)DFS = 0.86, HRTTR = 0.87, HROS = 0.86, p‐values = 0.11–0.17]. However, when considering alcohol type, ever consumers of red wine (n = 628) had significantly better outcomes than never consumers (HRDFS = 0.80, HRTTR = 0.81, HROS = 0.78, p‐values = 0.01–0.02). Favorable outcomes were confirmed in patients who consumed 1‐30 glasses/month of red wine (n = 601, HR = 0.80–0.83, p‐values = 0.03–0.049); there was a suggestion of more favorable outcomes in patients who consumed >30 glasses/month of red wine (n = 27, HR = 0.33–0.38, p‐values = 0.05–0.06). Beer and liquor consumption were not associated with outcomes. Although alcohol consumption was not associated with colon cancer outcomes overall, mild to moderate red wine consumption was suggestively associated with longer OS, DFS and TTR in stage III colon cancer patients.