Letter to the Editor: Liver transplantation for colorectal metastasis – selection criteria, outcomes, and management recurrence: a systematic review and meta-analysis

To the Editor, We read with great interest the comprehensive systematic review by Sayed Ahmed and colleagues, which cements the evolving role of liver transplantation for unresectable colorectal liver metastases[1]. Reporting a pooled 5-year overall survival of 54% across 377 patients, this study marks a pivotal milestone and validates transplantation as a superior alternative to palliative chemotherapy for selected candidates. However, several critical issues warrant further discussion. This correspondence is compliant with the TITAN Guidelines 2025—governing declaration and use of AI[2]. While the authors rightly highlight the utility of the Oslo Score and Metabolic Tumor Volume, these morphological metrics remain inherently static. They detect macroscopic burden but fail to identify the occult micrometastatic reservoir responsible for the high recurrence rate. We argue that the future of selection lies not in morphology but in liquid biopsy. The current observation period is arbitrary and should be upgraded to a molecular washout criterion. Circulating tumor DNA provides a dynamic assessment of tumor biology, and recent data indicate that post-chemotherapy clearance is the strong predictor of disease-free survival[3]. Integrating longitudinal circulating tumor DNA profiling could theoretically identify the patients destined to recur and thereby spare scarce grafts for those with true biological clearance. Furthermore, the review discusses surgical outcomes but overlooks the specific vascular cost of the selection process. Candidates for transplant oncology have typically endured extensive regimens of oxaliplatin and bevacizumab to demonstrate stability. These agents are known vascular toxins associated with sinusoidal obstruction syndrome and endothelial dysfunction[4]. The higher incidence of hepatic artery thrombosis in this population exceeding rates in benign indications is likely a direct sequela of this neoadjuvant toxicity rather than surgical chance. Future guidelines should acknowledge this mechanistic link and advocate for distinct vascular reconstruction protocols in heavily pre-treated recipients. Finally, the ethical calculus of organ allocation remains the greatest barrier to adoption. The authors discuss living donor liver transplantation as a solution yet standard right lobe donation carries a donor mortality risk that is difficult to justify for a recipient with a 50% recurrence probability. To truly scale this practice ethically, we should champion the RAPID procedure[5]. By utilizing small left lateral section grafts, which carry negligible donor risk, we can align the ethical cost of donation with the oncological reality of the recipient.