Impact of circumferential resection margin on survival in ampullary cancer: retrospective analysis

Abstract

Background: Ampullary carcinoma is a clinically variable entity. This study aimed to evaluate prognostic factors for the outcome of resected ampullary carcinoma patients with particular intent to analyse the influence of surgical radicality.

Methods: Patients undergoing resection between 2002 and 2017 were analysed. Clinicopathological parameters, perioperative outcome and survival were examined. Risk factor analysis for postresection survival was performed. Resection margin status was evaluated according to the revised classification for pancreatic adenocarcinoma.

Results: A total of 234 patients were identified, 97.9 per cent (n = 229) underwent formal resection, while 2.1 per cent (n = 5) underwent ampullary resection. Histological subtypes were 46.6 per cent (n = 109) pancreatobiliary, 34.2 per cent (n = 80) intestinal, 11.5 per cent (n = 27) mixed, and 7.7 per cent (n = 18) undetermined. In the pancreatobiliary group, tumours were more advanced with more vascular resections, pT4 stage, G3 differentiation and pN+ status. Five-year overall survival was significantly different for pancreatobiliary compared to intestinal (51.7 per cent versus 72.8 per cent, P = 0.0087). In univariable analysis, age, pT4 stage, pN+, pancreatobiliary subtype and positive resection margin were significantly associated with worse overall survival. Long-term outcome was significantly better after true R0 resection (circumferential resection margin-, tumour clearance >1 mm) compared with circumferential resection margin+ (<1 mm) and R1 resections (5-year overall survival: 69.6 per cent, median overall survival 191 months versus 42.4 per cent and 53 months; P = 0.0017).

Conclusion: Postresection survival of ampullary carcinoma patients is determined by histological subtype and surgical radicality. Intestinal differentiation is associated with less advanced tumour stages and better differentiation, which is reflected in a significantly better overall survival compared to pancreatobiliary differentiation. Despite this, true R0-resection is a prognostic key determinant in both entities, achieving 5-year survival in two-thirds of patients.