Value of positron emission tomography with [F-18]fluorodeoxyglucose in patients with colorectal liver metastases: a prospective study

T. Ruers, B. Langenhoff, N. Neeleman, G. Jager, S. Strijk, T. Wobbes, F. Corstens and W. Oyen

Departments of Surgery, Nuclear Medicine, and Radiology, University Medical Center Nijmegen, Nijmegen, the Netherlands.
Jan, 2002


To assess prospectively the value of fluor-18-deoxyglucose (FDG) positron emission tomography (PET), in addition to conventional diagnostic methods (CDM), as a staging modality in candidates for resection of colorectal liver metastases.In 51 patients analyzed for resection of colorectal liver metastases, clinical management decisions were recorded after a complete work-up with CDM. Afterward, FDG-PET scans were performed and any change of clinical management according to FDG-PET results was carefully documented. Discordances between FDG-PET and CDM results were identified and related to the final diagnosis by histopathology, intraoperative findings, and follow-up.In 10 (20\%) out of 51 patients, clinical management decisions based on CDM were changed after FDG-PET findings were known. FDG-PET detected unresectable pulmonary (n = 5) and hepatic metastases (n = 1) and ruled out extrahepatic (n = 2) and hepatic disease (n = 2). Due to FDG-PET, eight patients were spared unwarranted liver resection or laparotomy and two other patients were identified as candidates for liver resection. When the results of FDG-PET were regarded as decisive in a retrospective analysis, potential change of management was 29\% (15 patients). FDG-PET and CDM showed discordant extrahepatic results in 11 patients (22\%) and discordant hepatic results in eight patients (16\%). Compared with CDM, FDG-PET resulted in true upstaging (n = 11), true downstaging (n = 5), false upstaging (n = 1), and false downstaging (n = 2). The detection rate of liver metastases on a lesion basis was generally better for computed tomography than for FDG-PET (80\% v 65\%); this was related to tumor size.FDG-PET as a complementary staging method improves the therapeutic management of patients with colorectal liver metastases, especially by detecting unsuspected extrahepatic disease.