Prognostic implications of the standardized study of resection margins in pancreatic cancers.
INTRODUCTION
Involvement of surgical resection margins is a fundamental prognostic factor in pancreatic oncological surgery. However, there is a lack of standardized histopathology definition. The aims of this study are to investigate the real rate of R1 resections when surgical specimens are evaluated according to a standardized protocol and to study its survival implications.


PATIENTS Y METHODS
One hundred consecutive surgically resected patients with pancreatic ductal adenocarcinoma were included in the study. They were further divided in 2 groups: pre-protocol, evaluated before the introduction of the standardized protocol and post-protocol, analyzed with the standardized protocol.


RESULTS
R0 resection rate in the pre-protocol group was 78%, falling to 47% after the introduction of the standardized protocol (p=0,003). The posterior retroperitoneal margin was the most frequently involved margin. In cases with tumors located at the pancreatic head and analyzed according to the standardized protocol R1 involvement negatively affected survival. Median survival in the R0 group was 22 months versus 16 in those with the margin involved (HR: 2.044; IC 95% 1,00-4,16; P=.043).


CONCLUSIONS
Standardized evaluation of the retroperitoneal margins in pancreatic cancer increases the rate of R1 patients. In cases with pancreatic cancer located at the pancreatic head involvement of posterior retroperitoneal margin significantly decreases survival.