Observational Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 14, 2017; 23(26): 4815-4822
Published online Jul 14, 2017. doi: 10.3748/wjg.v23.i26.4815
Extreme liver resections with preservation of segment 4 only
Silvio Marcio Pegoraro Balzan, Vinícius Grando Gava, Marcelo Arbo Magalhães, Marcelo Luiz Dotto
Silvio Marcio Pegoraro Balzan, Marcelo Arbo Magalhães, Marcelo Luiz Dotto, Department of Pharmacy and Biology, University of Santa Cruz do Sul, 96810-110 Santa Cruz do Sul, Brazil
Silvio Marcio Pegoraro Balzan, Vinícius Grando Gava, Department of Surgery, Hospital Moinhos de Vento, 90035 Porto Alegre, Brazil
Author contributions: Balzan SMP, Gava VG and Magalhães MA designed the research, treated the patients, collected and analyzed the data, and wrote the paper; Dotto ML treated the patients and wrote the paper; all authors read and approved the final version for publication.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Hospital Ana Nery.
Conflict-of-interest statement: All authors declare no conflict of interest in relation to this study or its publication.
Data sharing statement: Technical appendix, statistical code and dataset are available from the corresponding author at sbalzan@hotmail.com. The data were anonymized and, thus, informed consent was not required from the participants.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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/
Correspondence to: Silvio Marcio Pegoraro Balzan, PhD, Department of Pharmacy and Biology, University of Santa Cruz do Sul, Rua Marechal Deodoro, 1139, 96810-110 Santa Cruz do Sul, Brazil. silviobalzan@unisc.br
Telephone: +55-51-37152824 Fax: +55-51-37152824
Received: January 29, 2017
Peer-review started: February 8, 2017
First decision: March 16, 2017
Revised: May 3, 2017
Accepted: June 9, 2017
Article in press: June 12, 2017
Published online: July 14, 2017
Abstract
AIM

To evaluate safety and outcomes of a new technique for extreme hepatic resections with preservation of segment 4 only.

METHODS

The new method of extreme liver resection consists of a two-stage hepatectomy. The first stage involves a right hepatectomy with middle hepatic vein preservation and induction of left lobe congestion; the second stage involves a left lobectomy. Thus, the remnant liver is represented by the segment 4 only (with or without segment 1, ± S1). Five patients underwent the new two-stage hepatectomy (congestion group). Data from volumetric assessment made before the second stage was compared with that of 10 matched patients (comparison group) that underwent a single-stage right hepatectomy with middle hepatic vein preservation.

RESULTS

The two stages of the procedure were successfully carried out on all 5 patients. For the congestion group, the overall volume of the left hemiliver had increased 103% (mean increase from 438 mL to 890 mL) at 4 wk after the first stage of the procedure. Hypertrophy of the future liver remnant (i.e., segment 4 ± S1) was higher than that of segments 2 and 3 (144% vs 54%, respectively, P < 0.05). The median remnant liver volume-to-body weight ratio was 0.3 (range, 0.28-0.40) before the first stage and 0.8 (range, 0.45-0.97) before the second stage. For the comparison group, the rate of hypertrophy of the left liver after right hepatectomy with middle hepatic vein preservation was 116% ± 34%. Hypertrophy rates of segments 2 and 3 (123% ± 47%) and of segment 4 (108% ± 60%, P > 0.05) were proportional. The mean preoperative volume of segments 2 and 3 was 256 ± 64 cc and increased to 572 ± 257 cc after right hepatectomy. Mean preoperative volume of segment 4 increased from 211 ± 75 cc to 439 ± 180 cc after surgery.

CONCLUSION

The proposed method for extreme hepatectomy with preservation of segment 4 only represents a technique that could allow complete resection of multiple bilateral liver metastases.

Keywords: Hepatectomy, Colorectal liver metastases, Hepatic congestion, Liver regeneration, Liver resection, Liver failure

Core tip: Extreme hepatic resections with preservation of one segment only may be required for complete resection of multiple bilobar liver metastases. We evaluated a new technique of two-stage hepatectomy with preservation of segment 4 only. Stage one involves a right hepatectomy with middle hepatic vein preservation and associated left lobe congestion through reduction of the left hepatic vein diameter. This combination optimizes segment 4 regeneration while allowing the left lobe (to be resected) to maintain function with reduced hypertrophy. Stage two involves a left lobectomy. Hypertrophy rates of non-congested segment 4 were significantly greater than in congested left lobe.