Citations

3591 Background: Adiponectin is a peptide hormone exclusively secreted by adipocytes that plays a role in immune regulation and in the host inflammatory response to cancer. We examined postsurgical adiponectin levels in relationship to tumor infiltrating lymphocytes (TILs), clinicopathological features, vitamin D status, and patient survival in participants in a phase 3 trial of adjuvant chemotherapy. Methods: Plasma adiponectin and 25-hydroxyvitamin D [25(OH)D] were analyzed by radioimmunoassay in 600 patients with stage III colon carcinoma who received adjuvant FOLFOX +/- cetuximab. TIL densities were determined at light microscopy in routine histopathological sections. The associations between adiponectin and 25(OH)D, TILs, other factors were evaluated by Fisher’s Exact, Chi-squared, t-test, and Kruskal-Wallis tests where appropriate. The association between adiponectin or 25(OH)D with disease-free survival (DFS), time to recurrence (TTR) and overall survival (OS) were evaluated by multivariable Cox regression, adjusting for body mass index (BMI), race, T, N stage, performance status, tumor location, TILs, BRAF/KRAS, and mismatch repair status. Results: A statistically significant and inverse association between adiponectin level and BMI was observed with lower levels found with obesity (BMI > 30 kg/m2) [p < 0.001]. The level of adiponectin was significantly lower in men vs women (p < 0.001), in blacks vs whites or Asians (p < 0.032), and in patients with fewer regional lymph node metastases (N1 vs N2 stage, p = 0.011). A significantly lower level of adiponectin was found in patients whose tumors had high vs low TIL densities (p = 0.040), but was unrelated to 25(OH)D. Insufficiency of 25(OH)D ( < 30 ng/ml) was detected in 291 (49%) of patients and was not associated with TILs. By multivariable analysis, adiponectin was not associated significantly with patient DFS (HRadj= 0.98, 95% CI 0.74-1.29, padj= 0.88) nor with OS nor time-to-recurrence (TTR). TIL densities were significantly prognostic, but 25(OH)D was not (DFS: HRadj= 1.12, 95% CI 0.85-1.47, padj= 0.44). No significant interaction was observed for adiponectin with TILs for the association with DFS. Conclusions: Lower adiponectin levels were associated with significantly increased TIL densities in colon cancers, indicating an enhanced anti-tumor immune response. In contrast to TILs, adiponectin was not independently associated with patient outcome. Nearly one-half of stage III patients were vitamin D insufficient, although 25(OH)D was not prognostic.

3604 Background: Limited research has investigated the role of variation in the host genome as a determinant of colon carcinoma (CC) outcomes, including toxicity due to therapeutic agents. We examined the relationship between germline genetic factors and treatment-associated serious adverse events (SAEs) in a population of CC patients in which treatment was standardized and follow-up for outcomes was uniformly conducted. Methods: Using existing biospecimens from CC patients with resected stage III disease in a phase III randomized trial of FOLFOX adjuvant chemotherapy with and without cetuximab (NCCTG N0147), genome-wide genotyping arrays were conducted for 2200 patients for a total of ~20 million single nucleotide polymorphisms (SNPs). Using logistic regression models we assessed SNP-specific associations with SAEs, utilizing a discovery-based approach to search the genome in an unbiased manner. Detailed information on SAEs was collected using the Common Toxicity Criteria for Adverse Events (CTCAE, v3.0). Analyses evaluating associations with specific classes of common grade ≥3 SAEs were performed, including gastrointestinal toxicities, neutropenia, and paresthesias. A threshold of P < 5x10-8was used to denote genome-wide significance. Results: Among patients who received FOLFOX, several SNPs on chr 15 near the ANP32A gene and on chr 2 near the CD207 gene were statistically significantly associated with grade ≥3 neuropathy. The strongest SNP-specific associations in these regions were in the range of odds ratio (OR) = 1.3, P = 2.8×10−10 and OR = 1.5, P = 2.7×10−10, respectively. Conclusions: Findings from this genome-wide analysis demonstrate the potential importance of germline genetic variation in influencing CC patients’ experience of specific toxicities to FOLFOX regimens. These results highlight two genomic regions of potential interest for understanding the biological mechanism for such toxicities, although further evaluation and replication is needed. Support: U10CA180821, U10CA180882, U10CA180820, U10CA180863, U10CA180888, CCSRI 021039, R01CA176272, Eli Lilly & Co, Pfizer, Sanofi. Clinical trial information: NCT00079274 .

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.

AbstractBackground: Prior studies have supported an inverse association between physical activity and colon cancer risk and suggest that higher physical activity may also improve cancer survival. Among participants in a phase III adjuvant trial for stage III colon cancer, we assessed the association of physical activity around the time of cancer diagnosis with subsequent outcomes.Methods: Before treatment arm randomization (FOLFOX or FOLFOX + cetuximab), study participants completed a questionnaire including items regarding usual daily activity level and frequency of participation in recreational physical activity (N = 1,992). Using multivariable Cox models, we calculated HRs for associations of aspects of physical activity with disease-free (DFS) and overall survival (OS).Results: Over follow-up, 505 participants died and 541 experienced a recurrence. Overall, 75% of participants reported recreational physical activity at least several times a month; for participants who reported physical activity at least that often (vs. once a month or less), the HRs for DFS and OS were 0.82 [95% confidence interval (CI), 0.69–0.99] and 0.76 (95% CI, 0.63–0.93), respectively. There was no evidence of material effect modification in these associations by patient or tumor attributes, except that physical activity was more strongly inversely associated with OS in patients with stage T3 versus T4 tumors (Pinteraction = 0.03).Conclusions: These findings suggest that higher physical activity around the time of colon cancer diagnosis may be associated with more favorable colon cancer outcomes.Impact: Our findings support further research on whether colon cancer survival may be enhanced by physical activity. Cancer Epidemiol Biomarkers Prev; 27(6); 696–703. ©2018 AACR.