Prognostic importance of standardized uptake value on F-18 fluorodeoxyglucose-positron emission tomography in biliary tract carcinoma.

F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) has been used for diagnosis and staging of malignant diseases. However, the prognostic significance of FDG uptake on PET had not been sufficiently evaluated in patients with biliary carcinoma. We performed a retrospective review of patients with biliary carcinoma imaged by FDG-PET to determine whether high uptake of FDG predicted overall survival independently of clinicopathological characteristics. Sixty-nine patients with biliary carcinoma underwent FDG-PET before cancer treatment. The maximum standard uptake value (maxSUV) was calculated as an index of FDG uptake. A receiver operating characteristic curve demonstrated a maxSUV of 6.3 to be the optimal cutoff point. The 3-year survival rate of patients with a maxSUV of 6.3 or less was 74.3%, whereas it was 44.1% for those with values greater than 6.3. Univariate analysis showed that the maxSUV was one of the significant prognostic factors for overall survival (P = 0.0119), whereas multivariate analysis showed that the independent predictors of survival were pN, pM, and pTNM staging. SUV analysis of FDG-PET was useful to predict the prognosis of biliary carcinoma. This information may assist in the guiding of treatment strategies before postoperative pathological assessment.