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Ann Surg Open
Ann Surg Open
AS9
Annals of Surgery Open
2691-3593
Wolters Kluwer Health, Inc. Two Commerce Square, 2001 Market Street, Philadelphia, PA 19103

AOSO-D-24-00176
00039
10.1097/AS9.0000000000000493
3
Letter to the Editor
Comment on “Surgical Margin of Resected Colorectal Liver Metastases: How Accurate Is Surgeon Prediction?”
Uchida Yoichiro MD, PhD *
Nishio Takahiro MD, PhD *
Hatano Etsuro MD, PhD *
From the * Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
Reprints: Yoichiro Uchida, M.D., Ph.D., Department of Surgery, Graduate School of Medicine, Kyoto University, 54 Kawara-cho, Shogoin, Sakyo-ku, Kyoto city, Kyoto, Japan, 606-8507. E-mail: uchiday@kuhp.kyoto-u.ac.jp.
11 9 2024
9 2024
5 3 e493e493
9 8 2024
12 8 2024
Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

OPEN-ACCESSTRUE
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pmcWe read with great interest the article recently published in Annals of Surgery by McIntyre et al1 “Surgical Margin of Resected Colorectal Liver Metastases: How Accurate Is Surgeon Prediction?”. This study demonstrates the accuracy of margin prediction from 190 prospectively collected preoperative and postoperative evaluations by attending surgeons and surgical fellows performing liver resections for colorectal liver metastases (CRLM) at a single institution. Although this study represents the first evaluation of a surgeon’s ability to accurately predict the pathologic margin following resection of CRLM, there are several important considerations before implementing these findings in clinical practice.

First, a major concern is the consistency between the preoperative surgical plan based on margin predictions and actual surgical procedures performed. Operators may modify the surgical plan based on the preoperative predictions and/or operative findings. In addition, appropriate modalities for preoperative margin prediction should be determined. In particular, preoperative three-dimensional (3D) simulation can provide a great deal of information, including detailed anatomical visualization, and precise hepatic area of portal perfusion and venous drainage, which can help surgeons safely perform precise and complicated operations to ensure surgical margins.2 3D simulation has been reported to help avoid submillimeter surgical margins in hepatectomy for CRLM.3 Intraoperative real-time navigation technology using indocyanine green (ICG) fluorescence imaging has also been shown to be useful for tumor detection, facilitating optimal surgical margins,2 even in cases of CRLM with preoperatively undetected intrabiliary tumor growth.4 Recent advances in imaging technology may have implications for preoperative simulation and intraoperative decision-making.

Second, contrast-enhanced intraoperative ultrasound is a useful modality for tumor detection and surgical margin planning, in addition to gadoxetic acid-enhanced magnetic resonance imaging or contrast-enhanced computed tomography, which are the current gold standard preoperative examinations.5 Together with real-time navigation technology including ICG imaging, intraoperative evaluation of surgical margins using contrast-enhanced intraoperative ultrasound provides accurate information and greatly influences the surgical strategy. The outcome of the margin status may not be influenced by preoperative prediction alone.

Third, the treatment strategy for patients with positive margins is important. There were 7 cases with positive margins in the study, and did they undergo subsequent re-resection to achieve R0? In the retrospective review of these cases, was there room to change the surgical plan during the preoperative evaluation? As the authors cited in the report by Sadot et al,6 it has been suggested that the margin status is significantly associated with prognosis. In the preoperative simulation of surgical procedures by predicting the margin status, treatment strategies, including post-treatment strategies, should be considered. Moreover, in the era of modern systemic chemotherapy, the survival benefit of re-resection for the R1 status of CRLM could be discussed.7

Overall, this study evaluated the surgeon’s ability to accurately predict the pathologic margin after resection of CRLM; however, the criteria for surgical decision-making based on preoperative and intraoperative evaluations were not defined, and the association between preoperative margin prediction and the outcome of the margin status remained unclear. Systematic margin prediction based on both preoperative and intraoperative evaluations should be performed in a prospectively designed study.

Disclosure: The authors declare that they have nothing to disclose.
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REFERENCES

1. McIntyre SM Soares KC Chou JF . Surgical margin of resected colorectal liver metastases: how accurate is surgeon prediction? Ann Surg. 2024;280 :311–316.38054376
2. Saito Y Shimada M Morine Y . Essential updates 2020/2021: current topics of simulation and navigation in hepatectomy. Ann Gastroenterol Surg. 2022;6 :190–196.35261944
3. Takamoto T Sano K Hashimoto T . Practical contribution of virtual hepatectomy for colorectal liver metastases: a propensity-matched analysis of clinical outcome. J Gastrointest Surg. 2018;22 :2037–2044.29980979
4. Seo S Ogiso S Toda R . Intraoperative indocyanine green imaging facilitates optimal surgical margin for colorectal liver metastasis with preoperatively undetected intrabiliary tumor growth. J Hepatobiliary Pancreat Sci. 2022;29 :e48–e49.34403558
5. Arita J Ono Y Takahashi M . Routine preoperative liver-specific magnetic resonance imaging does not exclude the necessity of contrast-enhanced intraoperative ultrasound in hepatic resection for colorectal liver metastasis. Ann Surg. 2015;262 :1086–1091.26010441
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