Survival outcome of small bowel adenocarcinoma (SBA) in the last 12 years: Meta-analysis.

e14667 Background: Due to rarity, management of SBA is currently controversial. Despite results from several single institutional studies showing no survival benefit with adjuvant chemotherapy, data extrapolated from established colorectal cancer studies are commonly used to manage this cancer. Here we report results of a meta-analysis on data from 14 retrospective studies published in English between years 2000 and 2011. Methods: PubMed database was searched using relevant keywords. Patients with SBA were included. Studies involving ampulary, periampulary and ileocecal valve tumors were excluded. The combined location and stage distribution were adjusted by sample size of each study. Primary outcome for the magnitude of benefit analysis were OS. Hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted. A random-effect model according to the method of DerSimonian and Laird was used; a heterogeneity test was used. The effect of adjuvant chemotherapy and/or radiation treatment after curative surgery was evaluated. Effect of stage, grade, and positive lymph node ratio was also evaluated. Results: With available information within 14 studies, mean age of patients was 59.3(95% CI: 56.4 and 62.1). Duodenum was the most common site of primary tumor followed by the jejunum, ileum and not specified sites (59.27%, 23.49%, 11.42%, and 3.03%), respectively. Overall median survival was 17.2 months (95% CI: 13.9 and 20.5). Adjuvant treatment vs. non adjuvant treatment showed a HR of 1.17 (95% CI: 0.71-1.93) that was not statistically significant. HR for low grade vs. high grade tumors was 3.90 (95% CI: 2.15- 7.06). HR for stage was 3.09 (95% CI: 0.89-10.67, p=0.07) comparing high stage with low stage which suggested a marginally statistically significant effect. HR for positive lymph node ratio (LNR) was 4.63 (95% CI: 2.67-8.03). Conclusions: Our meta-analysis suggests adjuvant treatment after cancer directed curative intent surgery does not improve overall survival compared to observation in SBA. Grade of tumor and positive LNR are significant predicators of overall survival whereas stage has marginally significant effect on survival. Future trials investigating new or innovative adjuvant therapy in SBA are needed.