Post-chemotherapy liver atrophy does not impact the outcome after hepatectomy performed under a parenchymal-sparing approach.

Background: Major hepatectomy in patients with colorectal liver metastases (CLM) and post-chemotherapy liver atrophy is associated with increased complications. Whether the performance of parenchymal-sparing hepatectomy (PSH) in those patients can be safer is unknown. Methods: Databases at two institutions were queried, and 74 CLM patients who underwent preoperative chemotherapy and curative PSH were reviewed. Pre- and post-chemotherapy total liver volumes (TLVs) were computed with Synapse 3D software, and the degree of atrophy was calculated as the difference in percentage. The cut-off value for significant degree of atrophy was set at 10%. Risk factors for post-chemotherapy liver atrophy were assessed using logistic regression, while multivariate analysis was computed to identify risk factors for postoperative complications. Results: With median CLM number of 6 (range, 1-20) and median CLM size of 3.3 cm (range, 1-14 cm), all patients underwent complex PSH. The 90-day mortality was 1%; Clavien-Dindo >2 complications occurred in 17%, with 6 (8%) post-hepatectomy liver failure (PHLF) events; 33 (45%) patients experienced ≥10% post-chemotherapy atrophy, of which pre-chemotherapy TLV was the only independent predictor [odds ratio (OR) =1.741; 95% confidence interval (CI): 1.120-2.386; P=0.02]. At multivariate analysis, none of the investigated variables showed significant association with PHLF or complications, which were not significantly increased in patients who experienced liver atrophy. Conclusions: As opposed to what observed after major hepatic resections, a significant degree of post-chemotherapy liver atrophy does not represent a source of postoperative complications in CLM patients undergoing PSH.