Liver transplantation for colorectal secondaries: on the way to validation.

PURPOSE OF REVIEW: Liver transplantation for nonresectable colorectal liver metastases (CRLMs) is an emerging field within transplant oncology. This review summarizes recent developments within this field. RECENT FINDINGS: More stringent selection criteria can yield 5-year survival rates that are similar to conventional indications for liver transplantation. Response to chemotherapy, low carcinoembryonic antigen levels, limited tumor volume and stable disease with observation time exceeding 12 months are fundamental requirements in this context. Radiomic analysis of pre transplant PET/computed tomography scans to determine metabolic tumor volume (MTV) in the liver seems particularly promising with regards to prediction of a favorable tumor biology. MTV values below 70 cm3 are associated with excellent long-term survival after transplantation, whereas the MTV threshold for liver resection seem far smaller. Recent studies put into question whether technical nonresectability per se is a valid inclusion criterion for liver transplantation. In patients with high hepatic tumor burden, but otherwise favorable prognostic features as assessed by the Oslo score, liver transplantation could possibly give a clinically relevant survival benefit compared with liver resection. SUMMARY: Liver transplantation is feasible treatment option in highly selected patients with nonresectable CRLMs. Robust and stringent selection criteria should be applied according to international consensus guidelines.