Survival and Recurrence in Pancreatobiliary Versus Intestinal Histology of Ampullary Carcinoma

Background: Ampullary carcinoma is rare with a more favourable prognosis compared to pancreatic ductal adenocarcinoma. The role of histological classification, including pancreatobiliary (PB) and intestinal (INT), on survival and recurrence outcomes in ampullary cancer is still debatable. Methods: 42 patients were identified between 1996-2010. Results: Nineteen classic pancreatoduodenectomies (PD) and 23 pylorus-preserving PDs were performed. Pathological review revealed 23, 18 and 1 patients with the PB, INT and mixed histology, respectively. Adjuvant chemoradiation (ACRT), chemotherapy, and radiation were given to 14 (33.3%), 4 (9.5%) and 2 (4.8%) patients, respectively. Recurrence-free survival (RFS) and overall survival (OS) from time of surgery were higher in the PB histological variant compared to INT (p=0.005 and 0.012, respectively). A landmark (LM) analysis found higher survival in the PB variant patients compared to INT (RFS p=0.023; OS p=0.048). There was no difference in RFS between both histological variants for patients who underwent surgery alone (p=0.42). However, the PB had higher RFS compared to the INT histology for patients who underwent ACRT (p=0.008). Conclusion: Ampullary carcinoma with PB histological variant was associated with significant survival benefit. The PB versus INT survival benefit was seen in the setting of ACRT, but not with surgery alone.