Comprehensive histological evaluation with clinical analysis of venous invasion in pancreatic ductal adenocarcinoma: From histology to clinical implications

Objectives Vascular invasion is a poor prognostic factor for pancreatic ductal adenocarcinoma (PDAC). However, our understanding of various features of vascular invasion is limited. Our aim is to comprehensively evaluate various features of vascular invasion, including status, type (lymphatic or venous), number of invasion foci, and histologic pattern (pancreatic intraepithelial neoplasia [PanIN]-like, conventional) in PDACs. Methods Various features of vascular invasion, including status, number of invasion foci, histologic patterns [pancreatic intraepithelial neoplasia (PanIN)–like, conventional], and size of involved vessels in 471 surgically resected PDACs were evaluated with all available hematoxylin and eosin (HE all Ps  4 cm), higher histologic grade, and lymph node metastasis, were independent prognostic factors of worse overall survival (all Ps  Conclusion Precise evaluation of venous invasion status, including number of foci of invasion, can provide additional prognostic information for patients undergoing surgical resection of PDAC, especially for those with advanced disease stage.