Metabolic Tumor Volume from 18 F-FDG PET/CT in Combination with Radiologic Measurements to Predict Long-Term Survival Following Transplantation for Colorectal Liver Metastases.

Simple Summary: Liver transplantation is emerging as a treatment option for patients with colorectal liver metastases. Due to the lack of liver donors, patient selection is vital. In this study, we report on the predictive value of combining metabolic tumor volume obtained from the pre-transplantation ¹⁸F-FDG PET/CT with the radiological measurements of tumor load (size, number, and tumor burden score) to select patients with the probability of long-term survival. Patients with low metabolic tumor volume have long disease-free survival, overall survival, and survival after relapse despite a high number of liver metastases and a high tumor burden score. This underlines the prognostic properties of metabolic active-tumor burden beyond conventional measurements. The aim of the present study is to report on the ability of metabolic tumor volume (MTV) of liver metastases from pre-transplant ¹⁸F-FDG PET/CT in combination with conventional radiological measurements from CT scans to predict long-term disease-free survival (DFS), overall survival (OS), and survival after relapse (SAR) after liver transplantation for colorectal liver metastases. The total liver MTV was obtained from the ¹⁸F-FDG PET/CT, and the size of the largest metastasis and the total number of metastases were obtained from the CT. DFS, OS, and SAR for patients with a low and high MTV, in combination with a low and high size, number, and tumor burden score, were compared using the Kaplan–Meier method and log–rank test. Patients with a low number of metastases and low MTV had a significantly longer OS than those with a high MTV, with a median survival of 151 vs. 26 months (p = 0.010). Patients with a high number of metastases and low MTV had significantly longer DFS, OS, and SAR than patients with a high MTV (p = 0.034, 0.006, and 0.026). The tumor burden score of group/zone 3, in combination with a low MTV, had a significantly improved DFS, OS, and SAR compared to those with a high MTV (p = 0.034, <0.001, and 0.006). Patients with a low MTV of liver metastases had a long DFS, OS, and SAR despite a high number of liver metastases and a high tumor burden score. [ABSTRACT FROM AUTHOR]