Two stage hepatectomy (TSH) versus ALPPS for initially unresectable colorectal liver metastases: A systematic review and meta-analysis

Although numerous comparisons between conventional Two Stage Hepatectomy (TSH) and Associating Liver Partition and Portal Vein Ligation for staged hepatectomy (ALPPS) have been reported, the heterogeneity of malignancies previously compared represents an important source of selection bias. This systematic review and meta-analysis aimed to compare perioperative and oncological outcomes between TSH and ALPPS to treat patients with initially unresectable colorectal liver metastases (CRLM).Main electronic databases were searched using medical subject headings for CRLM surgically treated with TSH or ALPPS. Patients treated for primary or secondary liver malignancies other than CRLM were excluded.A total of 335 patients from 5 studies were included. Postoperative major complications were higher in the ALPPS group (relative risk [RR] 1.46, 95% confidence interval [CI] 1.04-2.06, I2 = 0%), while no differences were observed in terms of perioperative mortality (RR 1.53, 95% CI 0.64-3.62, I2 = 0%). ALPPS was associated with higher completion of hepatectomy rates (RR 1.32, 95% CI 1.09-1.61, I2 = 85%), as well as R0 resection rates (RR 1.61, 95% CI 1.13-2.30, I2 = 40%). Nevertheless, no significant differences were achieved between groups in terms of overall survival (OS) (RR 0.93, 95% CI 0.68-1.27, I2 = 52%) and disease-free survival (DFS) (RR 1.08, 95% CI 0.47-2.49, I2 = 54%), respectively.ALPPS and TSH to treat CRLM seem to have comparable operative risks in terms of mortality rates. No definitive conclusions regarding OS and DFS can be drawn from the results.