Variations and adaptations of associated liver partition and portal vein ligation for staged hepatectomy (ALPPS): Many routes to the summit

Background. Our aim was to review variations from the originally described associated liver partition and portal vein ligation for staged hepatectomy (ALPPS) procedure and relevant clinical outcomes. Methods. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (ie, PRISMA) guidelines. A search of PubMed and Google Scholar was conducted until March 2015. Inclusion criteria were any publications reporting technical variations and descriptions of ALPPS. Exclusion criteria were insufficient technical description, data repeated elsewhere, or data that could not be accessed in English. Results. Initial search results returned 790 results; 46 studies were included in the final qualitative analysis. There were several alternatives described to the first stage of complete parenchymal split. Variations included partial ALPPS (partial split; hypertrophy of future liver remnant [FLR] 80-90%), radiofrequency-assisted liver partition and portal vein ligation (mean FLR hypertrophy 62%), laparoscopic microwave ablation and portal vein ligation (FLR hypertrophy 78-90 %), associating liver tourniquet and portal ligation for staged hepatectomy (median FLR hypertrophy 61 %), and sequential associating liver tourniquet and portal ligation for staged hepatectomy (FLR hypertrophy 77%) with a potential decrease in morbidity particularly after stage I. We analyzed several other variations, including considerations for segment IV, operative maneuvers, use of laparoscopy, identification of biliary complications, and liver containment. Conclusion. The current literature demonstrates a large variability in techniques of ALPPS that limits meaningful statistical comparisons of outcomes. Not physically splitting the liver at the first stage may decrease morbidity; however, randomized controlled trials are needed to determine benefits in technical variations.