The systematic review and meta-analysis by Bell et al.1 is of great interest and they are congratulated for their valuable study. However, the following comments on the results of the study are offered.
Bell et al.1 concluded that dual vein embolization was associated with a lower mortality rate compared with portal vein embolization, as depicted in the forest plot in Figure 4 of their article. However, a significant error in this forest plot erroneously altered the direction of the pooled effect size, creating a false impression of a beneficial effect on mortality rates. Specifically, the reported number of events in the two groups from the study by Le Roy et al.2 was inaccurate. The number of mortalities in the dual vein embolization group should be three, not one. Upon re-analysing the data using the fixed-effect model, there is no significant difference between the two groups (OR 0.43, 95% c.i. 0.16 to 1.12; P = 0.080) (Fig. 1), with no heterogeneity among the studies.
Fig. 1.
Corrected forest plot of mortality rate
DVE, dual vein embolization; PVE, portal vein embolization.
In conclusion, contrary to the findings of Bell et al.1, the corrected analysis of the available evidence does not support the superiority of dual vein embolization over portal vein embolization in reducing mortality in major hepatectomy. It is crucial to present this corrected finding to the readers of BJS Open to avoid misinterpretation of these results.
Contributor Information
Hani Oweira, Department of Surgery, Universitätsmedizin Mannheim, Heidelberg University, Mannheim, Germany.
Bassem Krimi, Department of General Surgery, Perpignan Hospital, Perpignan, France.
Amine Gouader, Department of General Surgery, Perpignan Hospital, Perpignan, France.
Ian Seiller, Department of Radiology, Perpignan Hospital, Perpignan, France.
Mohamed Ali Chaouch, Department of Visceral and Digestive Surgery, Fattouma Bourguiba Hospital, University of Monastir, Monastir, Tunisia.
Author contributions
Hani Oweira (Data curation, Writing—review & editing), Bassem Krimi (Data curation, Formal analysis, Funding acquisition, Visualization, Writing—review & editing), Amine Gouader (Conceptualization, Resources, Software), Ian Seiller (Software, Supervision, Validation, Writing—review & editing), and Mohamed Ali Chaouch (Conceptualization, Data curation, Project administration, Supervision, Validation, Visualization, Writing—original draft)
References
- 1. Bell RJ, Hakeem AR, Pandanaboyana S, Davidson BR, Prasad RK, Dasari BVM. Portal vein embolization versus dual vein embolization for management of the future liver remnant in patients undergoing major hepatectomy: meta-analysis. BJS Open 2022;6:zrac131 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2. Le Roy B, Gallon A, Cauchy F, Pereira B, Gagnière J, Lambert C et al. Combined biembolization induces higher hypertrophy than portal vein embolization before major liver resection. HPB (Oxford) 2020;22:298–305 [DOI] [PubMed] [Google Scholar]
- 3. Guiu B, Quenet F, Panaro F, Piron L, Cassinotto C, Herrerro A et al. Liver venous deprivation versus portal vein embolization before major hepatectomy: future liver remnant volumetric and functional changes. Hepatobiliary Surg Nutr 2020;9:564–576 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4. Heil J, Korenblik R, Heid F, Bechstein WO, Bemelmans M, Binkert C et al. Preoperative portal vein or portal and hepatic vein embolization: DRAGON collaborative group analysis. Br J Surg 2021;108:834–842 [DOI] [PubMed] [Google Scholar]
- 5. Hocquelet A, Sotiriadis C, Duran R, Guiu B, Yamaguchi T, Halkic N et al. Preoperative portal vein embolization alone with biliary drainage compared to a combination of simultaneous portal vein, right hepatic vein embolization and biliary drainage in Klatskin tumour. Cardiovasc Intervent Radiol 2018;41:1885–1891 [DOI] [PubMed] [Google Scholar]
- 6. Kobayashi K, Yamaguchi T, Denys A, Perron L, Halkic N, Demartines N et al. Liver venous deprivation compared to portal vein embolization to induce hypertrophy of the future liver remnant before major hepatectomy: a single centre experience. Surgery 2020;167:917–923 [DOI] [PubMed] [Google Scholar]
- 7. Laurent C, Fernandez B, Marichez A, Adam J-P, Papadopoulos P, Lapuyade B et al. Radiological simultaneous portohepatic vein embolization (RASPE) before major hepatectomy: a better way to optimize liver hypertrophy compared to portal vein embolization. Ann Surg 2020;272:199–205 [DOI] [PubMed] [Google Scholar]
- 8. Panaro F, Giannone F, Riviere B, Sgarbura O, Cusumano C, Deshayes E et al. Perioperative impact of liver venous deprivation compared with portal venous embolization in patients undergoing right hepatectomy: preliminary results from the pioneer centre. Hepatobiliary Surg Nutr 2019;8:329–337 [DOI] [PMC free article] [PubMed] [Google Scholar]