Comparative analysis of resected duodenal and ampullary adenocarcinoma.

Abstract

362 Background: Duodenal and ampullary adenocarcinomas are rare gastrointestinal cancers that share similar anatomic location and treatment strategy. We report a single-institution experience regarding the association between clinicopathologic features, treatment, and survival outcomes. Methods: A retrospective review of all patients resected with curative intent for duodenal adenocarcinoma (DUO) between 2005-2015 and ampullary adenocarcinoma (AMP) between 2011-2015 at VMMC was performed. For AMP, histologic subtyping into intestinal (IT) and pancreatobiliary (PB) phenotypes was determined. Demographic and clinicopathologic parameters were compared between DUO and AMP patients using Chi-square test. Overall survival was calculated using Kaplan-Meier analysis and prognostic factors were identified by univariate Cox regression. Results: Patients with DUO (n = 44) presented at higher T-stage (p = 0.002) and with larger tumors (4.35cm vs 2.33cm, p < 0.001) than AMP patients (n = 46). DUO patients had a higher rate of surgical complications (68% vs 41%, p = 0.01) with a trend for more pancreatic fistulas (36% vs 20%, p = 0.08). There was no difference in median overall survival between groups. Factors positively influencing survival included Caucasian race (p = 0.02) and normal CA19-9 level at diagnosis (p = 0.01). Tumor factors negatively influencing survival included positive lymph nodes (p = 0.04), lymphovascular invasion (p = 0.001), and perineural invasion (p = 0.02). Within AMP, the PB subtype presented at higher T-stage (p = 0.01) and with more positive lymph nodes (p = 0.03) than IT. There was no difference in survival between subtypes. Majority received adjuvant chemotherapy (88.8% in AMP, 76.3% in DUO), fewer received adjuvant radiotherapy (23.3% in AMP, 30% in DUO), but no survival difference was seen. Conclusions: DUO presents with larger tumors and higher T-stage than AMP and is associated with more surgical complications. The PB phenotype has more advanced pathologic features than IT. No survival difference was seen between anatomic locations or subtypes. Better surgical and chemotherapeutic strategies may be needed to overcome high risk features. Longer follow-up with more patients is needed to confirm these findings.