Complete or partial split in associating liver partition and portal vein ligation for staged hepatectomy: A systematic review and meta-analysis

BACKGROUND: Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been adopted by liver surgeons in recent years. However, high morbidity and mortality rates have limited the promotion of this technique. Some recent studies have suggested that ALPPS with a partial split can effectively induce the growth of future liver remnant (FLR) similar to a complete split with better postoperative safety profiles. However, some others have suggested that ALPPS can induce more rapid and adequate FLR growth, but with the same postoperative morbidity and mortality rates as in partial split of the liver parenchyma in ALPPS (p-ALPPS). AIM: To perform a systematic review and meta-analysis on ALPPS and p-ALPPS. METHODS: A systematic literature search of PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov was performed for articles published until June 2019. Studies comparing the outcomes of p-ALPPS and ALPPS for a small FLR in consecutive patients were included. Our main endpoints were the morbidity, mortality, and FLR hypertrophy rates. We performed a subgroup analysis to evaluate patients with and without liver cirrhosis. We assessed pooled data using a random-effects model. RESULTS: Four studies met the inclusion criteria. Four studies reported data on morbidity and mortality, and two studies reported the FLR hypertrophy rate and one study involved patients with cirrhosis. In the non-cirrhotic group, p-ALPPS-treated patients had significantly lower morbidity and mortality rates than ALPPS-treated patients [odds ratio (OR) = 0.2; 95% confidence interval (CI): 0.07–0.57; P = 0.003 and OR = 0.16; 95%CI: 0.03-0.9; P = 0.04]. No significant difference in the FLR hypertrophy rate was observed between the two groups (P > 0.05). The total effects indicated no difference in the FLR hypertrophy rate or perioperative morbidity and mortality rates between the ALPPS and p-ALPPS groups. In contrast, ALPPS seemed to have a better outcome in the cirrhotic group. CONCLUSION: The findings of our study suggest that p-ALPPS is safer than ALPPS in patients without cirrhosis and exhibits the same rate of FLR hypertrophy.