Radiographic tumor-vein interface as a predictor of intraoperative, pathologic, and oncologic outcomes in resectable and borderline resectable pancreatic cancer.

Background: Venous resection may be required to achieve complete resection of pancreatic cancers. We assessed the ability of radiographic criteria to predict the need for superior mesenteric-portal vein (SMV-PV) resection and the presence of histologic vein invasion.

Methods: All patients who underwent pancreaticoduodenectomy from 2004 to 2011 at the authors' institution were identified. Preoperative pancreatic protocol CT images were re-reviewed to characterize the extent of tumor-vein circumferential interface (TVI) as demonstrating no interface, ≤ 180° of vessel circumference, >180° of vessel circumference, or occlusion. Findings were correlated with the need for venous resection, histologic venous invasion, and survival.

Results: A total of 254 patients underwent pancreaticoduodenectomy and met inclusion criteria; 98 (39.6 %) required SMV-PV resection. In our cohort, 76.4 % of patients received neoadjuvant chemoradiation. The TVI classification system predicted with fair accuracy both the need for SMV-PV resection at the time of surgery and histologic invasion of the vein. In particular, 89.5 % of patients with TVI > 180° or occlusion required SMV-PV resection. Of those, 82.4 % had documented histologic SMV-PV invasion. TVI ≤ 180° was associated with favorable overall survival compared to a greater circumferential interface.

Conclusions: A tomographic classification of the tumor-SMV-PV interface can predict the need for venous resection, pathologic venous involvement, and survival. To assist in treatment planning, a standardized assessment of this anatomic relationship should be routinely performed.