Portal vein embolization (PVE) is a crucial preoperative procedure designed to induce hypertrophy of the future liver remnant (FLR) in patients requiring major hepatectomy. Among the embolic agents available, n-butyl cyanoacrylate (nBCA) combined with lipiodol has emerged as one of the most effective options for PVE, shares José Hugo Luz (Brazilian National Cancer Institute, Rio de Janeiro, Brazil), promoting a high yield of liver hypertrophy and requires only a minimal volume of contrast media.
One of the most compelling reasons to advocate for nBCA plus lipiodol in PVE is its high embolic efficiency. Unlike particulate embolics, such as polyvinyl alcohol (PVA) or gel foam, which can migrate or recanalise over time, nBCA polymerises upon contact with blood, forming a durable cast within the embolized portal branches, ensuring complete occlusion and effectively preventing collateral formation and enhancing FLR hypertrophy.
Studies have demonstrated that nBCA plus lipiodol induces faster and more significantliver hy hypertrophy of the FLR compared to other embolic materials. This is because it creates permanent vascular occlusion, the liver responds with an accelerated regenerative process, reducing time to surgery. De Baere et al and Tsoumakidou et al published animal studies which compared different embolic materials for PVE.1,2 They were able to show that nBCA plus lipiodol promoted a greater increase in the size of hepatic lobules and number of hepatocytes per lobule when compared with other embolic materials. Also, an increased hepatocyte and Kupffer cell proliferation in the nBCA-lipiodol group was identified. Tsoumakidou et al evaluated FLR growth with computed tomography (CT) imaging 14 and 28 days after PVE, and demonstrated significantly higher liver hypertrophy at both endpoints.
Two systematic meta-analyses were published in 2020 and 2021, together gathering more than 6,000 patients.3,4 In both publications PVE with nBCA plus lipiodol promoted higher liver hypertrophy, shorter procedure times, less radiation, less use of contrast and for the first time, less cost. The BEST FLR trial was a pivotal study evaluating optimal strategies to maximise FLR in patients undergoing major liver resection.5 In this trial, PVE with nBCA plus lipiodol generated greater and faster liver regeneration as seen at CT, compared with PVA particles plus coils, allowing for earlier surgical intervention for liver cancer. In this study of 60 participants with liver cancer, PVE with nBCA plus iodised oil produced greater absolute liver hypertrophy at CT compared with PVA particles plus coils (absolute hypertrophy of 46% vs. 30% at 14 days and 57% vs. 37% at 28 days, respectively). More participants in the nBCA plus iodised oil group presented sufficient liver hypertrophy for surgery two weeks after PVE compared with the PVA particles plus coils group (87% vs. 53%, respectively). nBCA plus lipiodol is the gold standard for PVE, offering superior embolization efficiency, superior hypertrophy induction, faster procedure time, less radiation exposure and lower cost.
References
- De Baere T, Denys A, Paradis V, et al. Comparison of four embolic materials for portal vein embolization: experimental study in pigs. Eur Radiol. Jun 2009;19(6):1435-42. doi:10.1007/s00330-008-1277-2
- Tsoumakidou G, Theocharis S, Ptohis N, et al. Liver hypertrophy after percutaneous portal vein embolization: comparison of N-butyl-2-cyanocrylate versus sodium acrylatevinyl alcohol copolymer particles in a swine model. Cardiovasc Intervent Radiol. Oct 2011;34(5):1042-9. doi:10.1007/s00270- 010-0046-1
- Ali A, Ahle M, Björnsson B, et al. Portal vein embolization with N-butyl cyanoacrylate glue is superior to other materials: a systematic review and meta-analysis. Eur Radiol. doi:10.1007/s00330-020- 07685-w
- Soykan EA AB, Lopez-Yurda M, Kuhlmann KFD, et al. Predictive Factors for Hypertrophy of the Future Liver Remnant After Portal Vein Embolization: A Systematic Review Cardiovasc Intervent Radiol: Springer; 2021.
- Luz JHM, Veloso Gomes F, Costa NV, et al. BestFLR Trial: Liver Regeneration at CT before Major Hepatectomies for Liver Cancer-A Randomized Controlled Trial Comparing Portal Vein Embolization with N-Butyl-Cyanoacrylate Plus Iodized Oil versus Polyvinyl Alcohol Particles Plus Coils. Radiology. Apr 2021:204055. doi:10.1148/radiol.2021204055.
José Hugo Luz is an interventional radiologist at the Brazilian National Cancer Institute in Rio de Janeiro, Brazil.
Disclosures: The author declared no relevant disclosures.
