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
Abstract
BACKGROUND

Preoperative portal vein embolization (PVE) is a widely used strategy to enable major hepatectomy in patients with insufficient liver remnant. PVE induces hypertrophy of the future liver remnant (FLR) and a shift of the functional reserve to the FLR. However, whether the increase of the FLR volume (FLRV) corresponds to the functional transition after PVE remains unclear.

AIM

To investigate the sequential relationship between the increase in FLRV and functional transition after preoperative PVE using 3-dimensional (3D) computed tomography (CT) and 99mTc-galactosyl-human serum albumin (99mTc-GSA) single-photon emission computed tomography (SPECT) fusion images.

METHODS

Thirty-three patients who underwent major hepatectomy following PVE at the Department of Gastroenterological Surgery I, Hokkaido University Hospital between October 2013 and March 2018 were enrolled. Three-phase dynamic multidetector CT and 99mTc-GSA SPECT scintigraphy were performed at pre-PVE, and at 1 and 2 wk after PVE; 3D 99mTc-GSA SPECT CT-fused images were constructed from the Digital Imaging and Communications in Medicine data using 3D image analysis system. Functional FLRV (FFLRV) was defined as the total liver volume × (FLR volume counts/total liver volume counts) on the 3D 99mTc-GSA SPECT CT-fused images. The calculated FFLRV was compared with FLRV.

RESULTS

FFLRV increased by a significantly larger extent than FLRV at 1 and 2 wk after PVE (P < 0.01). The increase in FFLRV and FLRV was 55.1% ± 41.6% and 26.7% ± 17.8% (P < 0.001), respectively, at 1 wk after PVE, and 64.2% ± 33.3% and 36.8% ± 18.9% (P < 0.001), respectively, at 2 wk after PVE. 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. The biopsy at 4 wk after PVE showed macro- and micro-vesicular steatosis of more than 40%, which improved to 10%. Radical resection was performed at 13 wk after PVE. The patient recovered uneventfully without any symptoms of pos-toperative liver failure.

CONCLUSION

The functional transition lagged behind the increase in FLRV after PVE in some cases. Evaluating both volume and function is needed to determine the optimal timing of hepatectomy after PVE.

Keywords: Preoperative portal vein embolization, Hepatectomy, 99mTc-galactosyl-human serum albumin single-photon emission computed tomography, Future liver remnant volume, Functional transition, Fatty liver change

Core Tip: Preoperative portal vein embolization (PVE) induces hypertrophy of the future liver remnant (FLR) and a shift of the functional reserve to the FLR. However, whether the increase in FLR volume (FLRV) corresponds to the functional transition after PVE remains unclear. We investigated the sequential relationship between the increase in the FLRV and the functional transition after preoperative PVE. The functional transition lagged behind the increase in FLRV after PVE in 3 of the 33 cases. Evaluating both volume and function is needed to determine the optimal timing of hepatectomy after PVE.