Intensified Histopathological Work-Up after Pancreatic Head Resection Reveals Relevant Prognostic Markers.

Introduction: Local recurrence remains a major problem after pancreatic head resection. Intensified histopathological work-up of surgical specimens after pancreatic head resection has revealed an increased number of incomplete resections (R1) depending on tumor infiltration front at the resection margins (RMs). It remains unclear to which extent the increased R1 resection rate has a clinical relevance for the patients' prognosis. Materials and Methods: Pancreatic head resections between 2006 and 2012 were histologically intensively worked-up by a previously described protocol. The distance between the tumor infiltration front and the resection planes or organ surfaces was documented. The impact of the size of the tumor and an additional portal vein resection was analyzed. The effect of a R1 resection status on development and type of recurrence was evaluated. Results: A total of 203 pancreatic head resections were evaluated. Different definitions of R1 resection were applied. These led to significantly different prognosis for patients. A greater distance between the tumor infiltration front and the resection plane or organ surface was associated with a better outcome for the patients. For the ventral surface, the mesopancreas and the pancreatic body these differences were statistically significant comparing the different R1 definitions. For the dorsal surface, a significant difference in prognosis was found if the tumor was >2 mm away from the resection surface. A tumor size of 3 cm was identified to play a relevant role for the prognosis. Patients who had a portal vein resection without a histologically proven infiltration showed a statistically significant higher overall survival. Patients with R1 resection were at highest risk for developing local recurrence as well as distant metastasis. Conclusion: Intensified histopathological work-up with an increased number of R1 resections has a clinical relevance for patients' prognosis. Tumors with a smaller size or with a greater distance to the organ surface or RM have a better outcome. [ABSTRACT FROM AUTHOR]