Comparison of Conventional Imaging and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Diagnostic Accuracy of Staging in Patients With Intrahepatic Cholangiocarcinoma

18F-fluorodeoxyglucose positron emission tomography and computed tomography (18F-FDG PET-CT) is increasingly used in the diagnosis, prognosis, staging, and treatment monitoring of many tumor types. However, only a small number of studies have reported the use of 18F-FDG PET-CT in intrahepatic cholangiocarcinoma (ICC). This study aimed to examine the accuracy of tumor staging in ICC by using 18F-FDG PET-CT. Between January 2009 and December 2020, patients with suspected ICC were retrospectively enrolled in the study and underwent imaging. The sensitivity and specificity of 18F-FDG PET-CT, CT, and magnetic resonance imaging (MRI) in detecting tumors, satellite focus, vascular invasion, and lymph node metastases were analyzed. The efficacy of 18F-FDG PET-CT for tumor staging was evaluated. Of the 110 patients who were enrolled in the study, 52 underwent surgical treatment and 45 were histologically diagnosed with ICC. When compared with CT or MRI, 18F-FDG PET-CT had similar sensitivity and specificity values for diagnosing satellite focus and vascular and bile duct invasion; however, PET-CT showed higher accuracy in diagnosing regional lymph node metastases. The accuracy of tumor staging by 18F-FDG PET-CT was higher than that by CT/MRI. Thus, 18FDG PET-CT may support tumor staging in ICC.