Retrospective Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. Feb 27, 2021; 13(2): 153-163
Published online Feb 27, 2021. doi: 10.4240/wjgs.v13.i2.153
Functional transition: Inconsistently parallel to the increase in future liver remnant volume after preoperative portal vein embolization
Yosuke Tsuruga, Toshiya Kamiyama, Hirofumi Kamachi, Tatsuya Orimo, Shingo Shimada, Akihisa Nagatsu, Yoh Asahi, Yuzuru Sakamoto, Tatsuhiko Kakisaka, Akinobu Taketomi
Yosuke Tsuruga, Toshiya Kamiyama, Hirofumi Kamachi, Tatsuya Orimo, Shingo Shimada, Akihisa Nagatsu, Yoh Asahi, Yuzuru Sakamoto, Tatsuhiko Kakisaka, Akinobu Taketomi, Department of Gastroenterological Surgery I, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
Author contributions: Tsuruga Y, Kamiyama T and Kamiachi H designed the research study; Tsuruga Y, Kakisaka T, Orimo T, Shimada S, Nagatsu A, Asahi Y and Sakamoto Y gave substantial contributions to acquisition of data; Tsuruga Y and Kamiyama T analyzed the data and wrote the manuscript; Taketomi A gave final approval of the version to be published; all authors have read and approved the final manuscript.
Institutional review board statement: This retrospective study was approved by the Institutional Review Board of Hokkaido University Hospital for Clinical Research on November 29, 2018 (Approval No. 018-0263).
Informed consent statement: This study was reviewed and approved by the Institutional Review Board of Hokkaido University Hospital for Clinical Research (Approval No. 018-0263), which waived the need for written informed consent due to the retrospective design.
Conflict-of-interest statement: The authors declare no conflicts of interest associated with this manuscript.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Yosuke Tsuruga, MD, PhD, Doctor, Department of Gastroenterological Surgery I, Hokkaido University Graduate School of Medicine, North 15, West 7, Kita-ku, Sapporo 060-8638, Japan. ytsuruga@d2.dion.ne.jp
Received: November 16, 2020
Peer-review started: November 16, 2020
First decision: December 20, 2020
Revised: December 26, 2020
Accepted: January 14, 2021
Article in press: January 14, 2021
Published online: February 27, 2021
ARTICLE HIGHLIGHTS
Research background

Preoperative portal vein embolization (PVE) is a widely used strategy to enable major hepatectomy in patients with insufficient liver remnant. The timing of hepatectomy after PVE has been usually determined from future liver remnant volume (FLRV) based on computed tomography (CT) volumetry.

Research motivation

PVE induces hypertrophy of the future liver remnant (FLR) and a shift of the functional reserve to the FLR. However, whether the increase in FLRV corresponds to the functional transition after PVE remains uncertain.

Research objectives

The present study investigated the sequential relationship between the increase in the FLRV and functional transition after preoperative PVE.

Research methods

Thirty-three patients who underwent major hepatectomy following PVE were enrolled in this retrospective study. Functional FLRV (FFLRV) was defined as the total liver volume × (FLR volume counts / total liver volume counts) on the 3-dimensional 99mTc-galactosyl-human serum albumin (99mTc-GSA) single-photon emission CT CT-fused images. The calculated FFLRV was compared with FLRV.

Research results

FFLRV increased by a significantly larger extent than FLRV at 1 and 2 wk after PVE (P < 0.01); however, in 3 of the 33 patients, FFLRV levels decreased below FLRV at 2 wk. One of the three patients showed rapidly progressive fatty changes in FLR.

Research conclusions

The results indicate that functional transition lagged behind the increase in FLRV after PVE in some cases. The evaluation of both volume and function by CT volumetry and 99mTc-GSA are needed to determine the optimal timing of hepatectomy after PVE for preventing fatal liver failure after major hepatectomy.

Research perspectives

Further research is needed to elucidate the underlying mechanism of the functional transition delay and fatty changes in FLR.