Liver transplantation for unresectable colorectal liver metastases: Patient selection, timing, and the emerging role of living donor grafts

Colorectal liver metastases (CRLM) sit at the junction of oncology and transplantation.Hepatectomy remains the only widely accepted curative treatment, yet many patients have liver-confined disease that cannot be cleared because of bilobar distribution, an insufficient future remnant, or vascular involvement.Systemic and liver-directed therapies have expanded resectability, but a residual group remains permanently unresectable, and chemotherapy alone rarely cures them.Total hepatectomy with transplantation removes the entire tumor-bearing organ.The Norwegian SECA studies reported 5-year overall survival of 60% to 83% despite frequent relapse, and the randomized TransMet trial showed a substantial survival benefit of chemotherapy plus transplantation over chemotherapy alone in committee-selected candidates.The central challenge is therefore selection, not operative feasibility: deciding whose tumor biology justifies a graft and, with living donation, whose disease justifies exposing a healthy donor to major hepatectomy.Favorable features include liver-restricted disease on repeated staging, a controlled primary tumor, response or stability on systemic therapy, low carcinoembryonic antigen, limited metabolic tumor volume, an Oslo score of 0 or 1, and sufficient time for tumor behavior to declare itself.Progression on treatment, occult extrahepatic disease, BRAF V600E mutation, high metabolic burden, and a short interval from diagnosis argue against transplantation.This review traces the evolution of the evidence, proposes a practical approach to referral and timing, and addresses recurrence, post-transplant care, allocation, and donor ethics, with emphasis on settings where living donation is the realistic route to a graft.Using Korea as an example, it also outlines the current allocation status of CRLM under national policy, regulatory and institutional constraints on living donation for an oncologic indication, and the minimum dataset a national prospective registry should capture.