Expression of Matrix Metalloproteinase-9 in Surgically Resected Intrahepatic Cholangiocarcinoma

Background: Matrix metalloproteinase-9 (MMP-9) has recently been reported to be related to cancer cell invasion. This study was performed to clarify the expression of MMP-9 in surgically resected intrahepatic cholangiocarcinoma (IHCC).

Methods: In 37 patients with IHCC who underwent a surgical resection, the expression of MMP-9 and the clinicopathologic characteristics of MMP-9-positive IHCC were investigated. The expression of MMP-9 was immunohistochemically detected in 16 (43%) of 37 IHCC. The patients were divided into MMP-9 (-) IHCC (n = 21), MMP-9 (+) IHCC (n = 12), and MMP-9 (++) IHCC (n = 4).

Results: The survival rate after surgical resection in patients with MMP-9 (-), (+), and (++) IHCC, was 66%, 39%, and 0% at one year, 50%, 32% and 0% at 3 years, respectively (P = .001). The incidence rate of lymph node metastasis was 6 (28%) of 21 in MMP-9 (-) patients, 7 (58%) of 12 in MMP-9 (+) patients and 4 (100%) of 4 in MMP-9 (++) patients. The incidence rate of lymph node metastasis increased in proportion to an increase in the expression of MMP-9 in IHCC (P = .02). Recurrence in the lymph node was more common in patients with MMP-9 (+) and (++) cancers than in those with MMP-9 (-) cancers.

Conclusions: The expression of MMP-9 in IHCC was a prognostic factor related to lymph node metastasis.