Impact of microvessel density on lymph node metastasis and survival after curative resection of pancreatic cancer

The roles of angiogenesis and the most prominent angiogenic vascular endothelial growth factor (VEGF) in diseases of the pancreas remain controversial. We compared microvessel density (MVD) and VEGF status in normal pancreatic, chronic pancreatic, and pancreatic cancer (PC) tissues to establish their prognostic relevance. Eighty samples of PC tissue, 32 samples of normal pancreatic tissue, and 20 samples of chronic pancreatitis (cP) tissue were immunostained with monoclonal anti-CD31 and polyclonal anti-VEGF antibody. The MVD was correlated with clinicopathological features and survival. Microvessel density was higher in PC than in cP (P < 0.001). Residual tumor status was highly predictive for survival (P < 0.001). After stratification for residual tumor status, we identified lymph node metastasis (LNM) in more than two lymph nodes (P < 0.04) and high MVD (P < 0.03) as risk factors for mortality. Multivariate analysis revealed only a high MVD (P = 0.03, odds ratio 0.441, 95% confidence interval 0.211-0.821) as an independent predictor of poor survival. Vascular endothelial growth factor was found over stromal cells in cP and over ductal adenocarcinoma cells in PC. Vascular endothelial growth factor expression status was not predictive of survival (P < 0.07). This study confirms the role of angiogenesis in PC and identifies MVD as an independent prognostic factor in patients with curatively resected PC.