Abstract
BACKGROUND: The role of surgery and chemotherapy for stage IV small bowel adenocarcinoma (SBA) is still confused. The results from previous analyses have been limited by small sample sizes and different treatment regimens. METHODS: Patients with stage IV SBA were identified in the Surveillance, Epidemiology, and End Result Program (SEER) database. Cause-specific survival (CSS) and overall survival (OS) were calculated with Kaplan-Meier methods and log-rank test. Multiple logistic and Cox regression identified covariates associated with treatment options and survival. RESULTS: 1219 eligible patients were involved in this study. The median age was 67 (range, 20-95) with 655 (53.7%) males and 564 (46.3%) females. Age and primary tumor site were significantly associated with surgery performance, age was also significantly associated with chemotherapy (P < .01). To reduce bias, further six subgroups were divided by age (≤65 and >65) and primary tumor site (duodenum, jejunum and ileum). Chemotherapy and surgery conferred a benefit on survival of the whole cohort (the median CSS of different treatment groups were 17, 9, 4, and 1 month respectively, P < .001) and most subgroups (83.3%, 5/6). In multivariate analysis, surgery (P = .006), and chemotherapy (P = .038) are still independent factors of favorable CSS and OS. For patients with surgery (n = 362), radical surgery was not associated with better survival. CONCLUSION: For stage IV SBA patients, the present study showed that age and primary tumor site were significantly associated with treatment preference. Surgery and chemotherapy were consistently correlated with favorable survival for the whole cohort or most specific subgroups. However, compared with palliative surgery, significant association was not found in patients with radical surgery with better outcome. More prospective well-defined cohorts would add knowledge for this rare disease.