Oncological safety of portal vein embolization without prior tumour clearance in the future liver remnant followed by one-stage hepatectomy for bilateral colorectal liver metastases

BACKGROUND: Upfront portal vein embolization (PVE) without prior future liver remnant (FLR) clearing followed by a one-stage hepatectomy (OSH) for bilateral colorectal liver metastases (CRLM) can reduce the surgical burden of a two-stage approach, but oncological safety is not well described and comparisons with alternative two-stage procedures are lacking.

METHODS: A retrospective cohort of patients with bilateral CRLM and tumour in the FLR, undergoing liver resection between 2013 and 2021, was studied. The patients were divided into three groups: patients who underwent PVE with no prior tumour clearance in the FLR followed by an OSH (PVE-OSH); patients who underwent tumour clearance in the FLR followed by PVE (TSH-PVE; where TSH stands for two-stage hepatectomy); and patients who underwent associating liver partition and portal vein ligation for staged hepatectomy (ALPPS).

RESULTS: In total, 302 patients with bilateral CRLM were included, of whom 127 underwent PVE-OSH, 61 underwent TSH-PVE, and 114 underwent ALPPS. Except for age and Eastern Cooperative Oncology Group (ECOG) Performance Status, all baseline characteristics were comparable. The most rapid hypertrophy was experienced by ALPPS patients, followed by PVE-OSH patients. Successful resection could not be performed in 11% of PVE-OSH patients, 21% of TSH-PVE patients, and 4% of ALPPS patients (P < 0.001). During major resection, 23% of TSH-PVE patients required additional FLR resection/ablation and the median time from first intervention to major resection was 9 (interquartile range (i.q.r.) 7-13) weeks, compared with 6 (i.q.r. 5-8) weeks for PVE-OSH patients and 1 (i.q.r. 1-3) week for ALPPS patients (P < 0.001). Postoperative outcomes were comparable regarding liver failure, mortality, and overall survival. Multivariable regression analysis for liver recurrence identified the number of metastases (HR 1.04 (95% c.i. 1.00 to 1.07); P = 0.025) and ALPPS (HR 1.64 (95% c.i. 1.00 to 2.68); P = 0.048) as independent risk factors.

CONCLUSION: PVE-OSH can be performed safely for patients with a limited tumour burden in the FLR, thereby obviating the need for two-stage procedures.