Relationship between mucin expression and preoperative bile juice cytology in biliary tract carcinoma

The present study evaluated correlations between preoperative bile juice cytology and mucin expression of surgical specimens in biliary tract carcinoma. Twenty-five patients with biliary tract carcinoma surgically treated at our hospital, whose bile juice cytology had been evaluated before operation, were allocated to this study. Biliary cytology was classified into three categories based on the Papanicolaou classification. Immunohistochemical staining of tissues was performed using MUC1 and MUC2 monoclonal antibodies. Lesions showing MUC1 expression of ++ or higher and MUC2 expression of - were classified as Group A, and the remaining lesions as Group B. According to the epithelial site, preoperative cytology was highly correlated in Group A, while it was negative in Group B (p<0.05). In the advanced site of carcinomas, preoperative cytology tended to highly be positive in Group A, while it tended to be negative in Group B (p<0.05). These results suggest that the bile juice cytology results are affected by characteristics of mucin expression in the tissue. Based on the possibility that mucin expression correlates with the prognosis of each carcinoma, a positive cytological result suggests a poor prognosis for the carcinoma, which may be informative for predicting the post-operative courses and choosing treatments.