Catheter Tract Implantation Metastasis Diagnosed by F-18 FDG PET/CT After Percutaneous Transhepatic Biliary Drainage for Hilar Cholangiocarcinoma

We present a case of catheter tract implantation metastasis of hilar cholangiocarcinoma after preoperative percutaneous transhepatic biliary drainage (PTBD) on F-18 FDG PET/CT. A 65-year-old woman had received preoperative PTBD before a left hemihepatectomy due to hilar cholangiocarcinoma 17 months ago. Recently, the patient complained of pain in the right flank. Serum CEA and CA 19–9 levels were within the normal range. Contrast-enhanced abdominal CT was done and interpreted as no definite abnormality, so F-18 FDG PET/CT was undertaken and showed metastatic implantation on the right flank. On a retrospective review of the previous CT, a small nodule was noted at the corresponding site of the lesion on FDG PET/CT (Fig. 1). CT-guided biopsy was done and pathologic finding revealed metastasis from hilar cholangiocarcinoma (Fig. 2).