Twelve-year experience of "radical but conservative" liver surgery for colorectal metastases: impact on surgical practice and oncologic efficacy

Background: Liver surgery for colorectal metastases (CLM) is moving toward parenchyma-sparing approaches. The authors reported the technical feasibility of parenchyma-sparing hepatectomy for deeply located tumors, but its impact on daily practice and long-term outcomes remain unclear. Methods: The patients undergoing liver resection (LR) for CLM with vascular contact (first-/secondorder pedicle or hepatic vein (HV) trunk) were considered. Those undergoing major hepatectomy were excluded. The authors' technique included tumor-vessel detachment, partial resection of marginally infiltrated HVs, and detection of communicating vessels (CVs) among HVs to preserve outflow after HV resection. Results: Among 169 patients with major vascular contact, parenchyma-sparing LR was feasible in 146 (86%). Twenty-eight SERPS, 13 transversal hepatectomies, 6 mini-mesohepatectomies, and 4 liver tunnels were performed. Sixty-six (45%) patients underwent CLM-vessel detachment, 25 (17%) underwent partial HV resection, and 30 (21%) achieved outflow preservation by CV identification. The mortality and severe morbidity rates were 1.4% and 8.2%, respectively. The 5-year survival rate was 30.7%. The parenchyma-sparing strategy failed in 14 (7%) patients because of recurrence in the spared parenchyma or cut edge; 13 were radically retreated. Conclusion: Ultrasound-guided parenchyma-sparing surgery is feasible in most patients with ill-located CLMs. This procedure is safe and achieves adequate oncologic outcomes.