Clinicopathological Significance of Fatty Acid Synthase Expression in Carcinoma of the Ampulla of Vater

Objective: Increased fatty acid synthase (FAS) expression is detected in various cancers. It has been demonstrated that the intensity of FAS expression in cancer correlates with clinical outcome. Here, we investigated whether FAS expression in carcinoma of the ampulla of Vater has any relationship to clinical or pathological features. Methods: We studied 32 patients surgically treated for carcinoma of the ampulla of Vater in our hospital. We compared FAS immunohistochemical staining with other pathological features, including Ki-67, p53, and MUC1, and 2 staining, and with clinical findings. Results: Of these 32 cases, 16 were considered FAS-positive under our criteria. Pathologically, FAS positivity was correlated to Ki-67 positivity (p: 0.0045), but there was no significant relationship between FAS expression and p53 staining(p: 0.6715). FAS-positive cases showed a higher rate of lymph node metastases (p: 0.0373). However, FAS expression was not related to tumor size, differentiation of adenocarcinoma, duodenal invasion, pancreatic invasion and MUC1 or MUC2 positivity. Clinically, the disease survival rate and the overall survival rate of FASpositive cases was lower than that of FAS-negative ones (p: 0.0365, 0.0007). Conclusion: Histological FAS expression is related to aggressiveness of cancer of the ampulla of Vater and FAS expression can be considered to be a prognostic marker in cancer of the ampulla of Vater.