Clinical Characteristics of Patients Experiencing Pathologic Complete Response Following Neoadjuvant Therapy for Borderline Resectable/Locally Advanced Pancreatic Adenocarcinoma

Objectives: The purpose of this study is to describe clinical characteristics and outcomes of patients with borderline resectable pancreatic cancer (BRPC) or locally advanced pancreatic cancer (LAPC) who achieved pathologic complete response (pCR) following neoadjuvant therapy. Materials and Methods: A single institution clinical database for patients with pancreatic ductal adenocarcinoma was queried. Between 2008 and 2014 patients were identified with BRPC and LAPC, who underwent surgical resection after receiving neoadjuvant treatment. Clinical and pathologic features of the patients who achieved pCR were acquired retrospectively. Results: Six patients were identified to have pCR on pathology of the postoperative specimen. On the basis of pretreatment clinical staging, 2 patients were considered to have BRPC and 4 LAPC. Four patients received gemcitabine-based chemotherapy and 2 patients received FOLFIRINOX (5-fluorouracil, oxaliplatin, irinotecan, and leucovorin). Five of 6 patients received radiation therapy before operative resection. Operative procedures included distal pancreatectomy (n=3) and pancreatoduodenectomy (n=3). Pancreatic intraepithelial neoplasia 1 to 2 was present in 3 cases, and pancreatic intraepithelial neoplasia 3 in 1 case. During a median follow-up of 21.3 months, 2 patients died, with a median survival of 11.0 months (range, 10.4 to 11.6 mo). Four patients are alive and continue to follow-up with median survival of 28.7 months (range, 20.1 to 42.4mo). Conclusions: Multimodality neoadjuvant therapy may lead to complete pathologic response in a small number of patients with borderline resectable/locally advanced pancreatic adenocarcinoma. pCR to neoadjuvant therapy does not lead to cure in most cases, and the majority of patients appear to relapse locally or systemically.