Prognostic value of serum MUC5AC mucin in patients with cholangiocarcinoma

BACKGROUND. The authors recently showed that MUC5AC mucin, which is expressed aberrantly in tumor tissue, is present in significant concentrations in serum from patients with cholangiocarcinoma. Subsequently, determination of serum MUC5AC had high sensitivity and specificity for cholangiocarcinoma. In this study, the possible association between serum MUC5AC mucin and the clinical findings of the patients and their prognostic value were explored. METHODS. The expression of MUC5AC mucin in serum samples from 179 patients with histologically confirmed cholangiocarcinoma were determined using immunoblotting. RESULTS. Detection of serum MUC5AC was associated with patients with blood group Type A, larger-sized tumors (> 5 cm), and advanced-stage disease. Patients who had positive serum MUC5AC status had a significantly poorer prognosis (median survival, 127 days; 95% confidence interval [95% CI], 107-180 days) compared with patients who had negative serum MUC5AC status (median survival, 329 days; 95% CI, 199-458 days; P < 0.001). Multivariate analysis with adjustment for all covariates showed that patients who had positive serum MUC5AC status had a 2.5-fold higher risk of death compared with patients who had negative serum MUC5AC status (P < 0.001). CONCLUSIONS. Serum MUC5AC was associated with tumor burden. The determination of serum MUC5AC may be predictive of poor patient outcome and may be useful in selecting possible treatment options for patients with cholangiocarcinoma. Cancer 2003;98:1438-43. (C) 2003 American Cancer Society.