Alberts, Steven R.

Abstract Gastric cancer is a leading cancer health disparity among the Alaska Native (AN) people, occurring at a 3-fold higher incidence and 4-fold higher mortality rate in comparison to U.S. Non-Hispanic whites (NHW). AN gastric cancer patients have significant differences in tumor location and appearance compared to NHW patients. In addition, AN patients are younger at the time of diagnosis, 60 versus 69 years and have a lower 5-year survival rate of 10% compared to 22% of NHW gastric cancer patients. The purpose of this research was to understand the role of gene mutations, inflammation, and infection as possible factors in the promotion of gastric cancer in the AN population. In this study, we examined previously obtained tissue samples from AN gastric cancer patients diagnosed between 2006-2014 at the Alaska Native Medical Center. Using next-generation sequencing, immunohistochemistry and in situ hybridization, we evaluated for 50 cancer related gene mutations, the presence of the virus, Epstein-Barr virus (EBV), the bacterium, Helicobacter pylori (H. pylori), and inflammatory factors. Cancer related gene mutations were observed in 69% of gastric tumors from AN patients. The most commonly mutated genes were TP53 (30%), PIK3CA (13%), STK11 (6%), KRAS (5%), and PTEN (5%). Of particular interest, gene mutations were associated with patients who were younger at time of diagnosis (less than 55 years old) and had a history of chronic gastritis. Additionally, EBV is associated with 23% of AN gastric cancers, which is significantly higher than the 10% of EBV associated gastric cancer cases observed in other populations. EBV associated AN gastric cancer patients were more likely to have a history of chronic gastritis, prior or current H. pylori infection, and tobacco use. Notably, aberrant overexpression of the inflammatory factor cyclooxygenase 2 (COX-2) and the glycoprotein Mucin 1 (MUC1) in gastric cancer cells was significantly associated with a poorer prognosis among AN gastric cancer patients. Collectively, these findings indicate infection and inflammation are potential driving factors in the pathogenesis of gastric cancer among the AN people, which may have important clinical implications. Citation Format: Holly Martinson, Steven Alberts, Matthew Olnes. Infection, inflammation and cancer: Understanding Alaska Native cancer health disparities [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4239.

Objectives Prognostic factors for solid pseudopapillary neoplasms (SPN) of the pancreas have been incompletely defined in the literature. We aimed to use the National Cancer Database to describe survival and characterize prognostic factors in patients with pancreatic pseudopapillary neoplasms. Methods We identified 304 patients with pancreatic SPN diagnosed between 2004 and 2012 using the National Cancer Database. All patients were included in the survival analysis. Kaplan-Meier method, χ 2 , and log-rank tests were used for statistical analysis. Cox proportional hazard regression model was used for multivariate analysis. Results The median age at diagnosis was 36.5 years. Eighty-five percent of patients were female, 69% were white, and 25% were black. Metastases were observed in 5% of patients. Median tumor size was 5.1 cm. Ninety-two percent of patients underwent primary tumor resection. At 60 months, 98% of patients who underwent resection were alive, and 40% who did not undergo resection were alive. On multivariate analysis, female sex, resection of primary tumor, and absence of metastasis were correlated with improved survival. Conclusions Patients with SPN who undergo resection have an excellent survival at 5 years. Surgery should be considered in all patients with this diagnosis.

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.