Material and Method: Tissue samples from pancreatic ductal adenocarcinomas and ampulla of Vater carcinomas were obtained from 31 patients who underwent pancreticoduodenectomy for periampullary carcinoma. The study group was composed of 12 women and 19 men. Their median age was found to be 62.32 years (range 26-85 years). The parameters analyzed in the study included lymph node metastases, perineural invasion, differentiation, duodenal invasion, grade of intraepithelial neoplasia and p16 and cyclinD1 expression in tumoral and peritumoral pancreatic tissues.

Results: In both tumor groups, the loss of p16 protein expression was significantly correlated with perineural invasion (p=0.0001). Perineural invasion was more frequent in the pancreatic ductal adenocarcinoma group than the ampulla of Vater carcinoma group (p=0,01). When desmoplasia and lymphoplasmacytic stromal infiltration were examined, desmoplastic reaction was significantly higher in pancreatic ductal adenocarcinomas than ampulla of Vater carcinomas (p=0.01). No significant difference was observed between tumor groups for Cyclin D1 (p>0.05).