Clinical role of 18F-FDG PET-CT in suspected and potentially operable cholangiocarcinoma:: A prospective study compared with conventional imaging

OBJECTIVES: This study was conducted to evaluate the clinical role of integrated positron emission and computed tomography (PET-CT) in patients with suspected and potentially operable cholangiocarcinoma. METHODS: Between October 2005 and May 2007, 123 patients with suspected cholangiocarcinoma were enrolled in this study after diagnostic workup, including biliary dynamic computed tomography (CT) and magnetic resonance imaging/magnetic resonance cholangiopancreatography (MRI/MRCP) with magnetic resonance (MR) angiography. Patients with overt unresectable cholangiocarcinoma or gallbladder cancer diagnosed via conventional imaging were excluded. Consecutively, each enrolled patient underwent PET-CT. Data were prospectively collected and analyzed in comparison with CT and MRI/MRCP. RESULTS: The overall values for sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET-CT in primary tumor detection were 84.0%, 79.3%, 92.9%, 60.5%, and 82.9%, respectively. PET-CT demonstrated no statistically significant advantage over CT and MRI/MRCP in the diagnosis of primary tumor. According to different morphologic characteristics of cholangiocarcinoma, PET-CT showed no significant difference in detecting those of mass-forming, periductal-infiltrating, and intraductal-growing types. PET-CT revealed significantly higher accuracy over CT in the diagnosis of regional lymph nodes metastases (75.9% vs 60.9%, P=0.004) and distant metastases (88.3% vs 78.7%, P=0.004). Additional use of PET-CT for assessing resectability correctly showed different results from those determined by conventional imaging in 15 (15.9%) of 94 patients with cholangiocarcinoma. CONCLUSIONS: PET-CT improved the accuracy of preoperative staging in patients with cholangiocarcinoma planning to undergo curative resection. Thus, PET-CT had an important clinical impact on the selection of proper treatment.