Value of intraoperative neck margin analysis during Whipple for pancreatic adenocarcinoma: a multicenter analysis of 1399 patients.

INTRODUCTION: During pancreaticoduodenectomy (PD) for ductal adenocarcinoma, a frozen section (FS) neck margin is typically assessed, and if positive, additional pancreas is removed to achieve an R0 margin. We analyzed the association of this practice with improved overall survival (OS).
METHODS: Patients who underwent PD for pancreatic ductal adenocarcinoma from January 2000 to August 2012 at 8 academic centers were classified by neck margin status as negative (R0) or microscopically positive (R1) on the basis of FS and permanent section (PS). Impact on OS of converting an FS-R1-neck margin to a PS-R0-neck margin by additional resection was assessed.
RESULTS: A total of 1399 patients had FS neck margins analyzed. Median OS was 19.7 months. On FS, 152 patients (10.9%) were R1, and an additional 51 patients (3.6%) had false-negative FS-R0 margins. PS-R0-neck was achieved in 1196 patients (85.5%), 131 patients (9.3%) remained PS-R1, and 72 patients (5.1%) were converted from FS-R1-to-PS-R0 by additional resection. Median OS for PS-R0-neck patients was 21.1 months versus 13.7 months for PS-R1-neck patients (P < 0.001) and 11.9 months for FS-R1-to-PS-R0 patients (P < 0.001). Both FS-R1-to-PS-R0 and PS-R1-neck patients had larger tumors (P = 0.001), more perineural invasion (P = 0.02), and more node positivity (P = 0.08) than PS-R0-neck patients. On multivariate analysis controlling for adverse pathologic factors, FS-R1-to-PS-R0 conversion remained associated with significantly worse OS compared with PS-R0-neck patients (hazard ratio: 1.55; P = 0.009).
CONCLUSIONS: For patients who undergo pancreaticoduodenectomy for pancreatic ductal adenocarcinoma, additional resection to achieve a negative neck margin after positive frozen section is not associated with improved OS.