Matrix metalloproteinase 7 expression in ampullary carcinoma

Background: Matrix metalloproteinase 7 (MMP7) has largely been studied in pancreatic cancer which is the most common component of periampullary cancer in the western population. In India, the ampullary carcinoma is seen as the most common periampullary cancer in resected pancreaticoduodenectomies. We aimed to study the expression of MMP7 and its correlation with clinicopathological features in ampullary cancer. Materials and Methods: Consecutive cases of all ampullary cancer in a 3-year period were reviewed for histological differentiation (intestinal and pancreatobiliary) by morphology and immunohistochemistry (CDX2, MUC2, cytokeratin 20 [CK20], MUC1, cytokeratin 7 [CK7], and cytokeratin 17 [CK17]). All cases were stained for MMP7 and expression was correlated with histological variables, differentiation, and overall survival. Results: There were a total of 91 ampullary carcinomas (36 intestinal, 44 pancreatobiliary and 6 other types). Ampullary carcinoma showed MMP7 expression in 63.7% cases. Two-third of intestinal type and half of the pancreatobiliary type cancers showed MMP7 expression. MMP7 expression was significantly higher in low pathological T-stage of total ampullary carcinomas; however, it was seen more commonly in higher overall stage of the pancreatobiliary type compared to intestinal type of ampullary carcinoma. Overall survival in patients with MMP7 expression was lower compared to MMP7 negative patients. Conclusions: This is the first study on MMP7 expression in ampullary cancer. MMP7 expression was seen in nearly 64 % of ampullary cancer and showed a significant correlation with low pathological (T-) stage and high overall stage with a shorter survival. MMP7 can be explored as a target for MMP inhibitor therapy in the future