Prognostic value of MUC4 for mass-forming intrahepatic cholangiocarcinoma after hepatectomy.

Cholangiocarcinoma (CCA), a lethal malignancy afflicting many thousands of patients throughout the world, develops through a multi-step progression. We have established an oral thioacetamide-induced model of rat CCA recapitulating the histologic progression of human CCA, especially for mass-forming CCA (MF-CCA). Our previous DNA microarray study showed MUC4 is overexpressed in rat CCA. Herein, we investigated the prognostic value of MUC4 for predicting overall survival rate (OS) for MF-CCA patients undergoing hepatectomy. Overexpression of MUC4 in rat CCA is demonstrated by RT-PCR. From the archives of Chang Gung Memorial Hospital, 53 MF-CCA patients undergoing hepatectomy were selected for an immunohistochemical study of MUC4. Fifteen clinicopathological variables (including MUC4 staining status) were used for survival analysis. MUC 4 is overexpressed in rat CCA. Fifty-three MF-CCA patients, 26 men and 27 women, with a median age of 60 years (range: 29-89) were studied. During the median follow-up duration of 14.7 months, the OS rates at 1, 3, and 5 years were 58.8, 25.5, and 16.5%, respectively. Univariate analysis showed that an absence of physical findings, better nutritional status, small tumor size, negative lymph node metastasis, an absence of MUC4 staining, and curative hepatic resection were associated with favorable OS rate for MF-CCA patients after hepatectomy. However, multivariate Cox proportional hazard analysis showed that an absence of MUC4 staining, small tumor size, and curative hepatectomy independently predicted MF-CCA patients with favorable OS rate after hepatectomy. In conclusion, an absence of MUC4 staining, small tumor size, and curative hepatectomy could independently predict MF-CCA patients with favorable OS rate after hepatectomy.