Objective Definition and Optimized Strategy for "Biologically Borderline Resectable" Colorectal Liver Metastases

Takeshi Takamoto; Satoshi Nara; Daisuke Ban; Takahiro Mizui; Yoshiki Murase; Minoru Esaki; Kazuaki Shimada; Takuya Hashimoto; Masatoshi Makuuchi

doi:10.1007/s00268-023-07133-y

Objective Definition and Optimized Strategy for "Biologically Borderline Resectable" Colorectal Liver Metastases

World J Surg. 2023 Nov;47(11):2834-2845. doi: 10.1007/s00268-023-07133-y. Epub 2023 Aug 4.

Authors

Takeshi Takamoto¹, Satoshi Nara², Daisuke Ban², Takahiro Mizui², Yoshiki Murase², Minoru Esaki², Kazuaki Shimada², Takuya Hashimoto³, Masatoshi Makuuchi³

Affiliations

¹ Department of Hepatobiliary and Pancreatic Surgery, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-Ku, Tokyo, 104-0045, Japan. ttakamot@ncc.go.jp.
² Department of Hepatobiliary and Pancreatic Surgery, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-Ku, Tokyo, 104-0045, Japan.
³ Division of Hepato-Biliary-Pancreatic and Transplantation Surgery, Japanese Red Cross Medical Center, Tokyo, Japan.

PMID: 37540268
DOI: 10.1007/s00268-023-07133-y

Abstract

Background: The prognostic benefit of preoperative chemotherapy leading to conversion surgery for unresectable colorectal liver metastases (CRLM) is well recognized, while that of neoadjuvant chemotherapy (NAC) compared with upfront surgery (UFS) for resectable CRLM is negligible. This study aims to assess the prognostic benefit and search for optimal indication of NAC for resectable advanced CRLM by establishing an objective definition of biologically borderline resectable (bBR) CRLM.

Methods: A bicentric retrospective analysis of patients with CRLM undergoing curative-intent initial liver resection between 2007 and 2021 was performed. An original classification matrix was established, which reassessed technical resectability using virtual hepatectomy and oncological favorability using Beppu's nomogram. Patients with technically resectable but biologically unfavorable CRLM were classified into the bBR group. The propensity score matching analysis using preoperatively available factors was performed to assess long-term outcomes of the bBR-UFS and bBR-NAC groups.

Results: Of 831 patients reviewed, 240 were categorized into the bBR group: bBR -UFS (n = 139) and bBR-NAC (n = 101). Ten (10%) in the bBR-NAC group (n = 101) experienced biological status change from unfavorable to favorable after NAC (Biological Conversion) and showed significantly longer overall survival (hazard ratio 5.63, 95% confidence interval 1.37-23.1; P = 0.016) than the bBR-UFS group. However, after propensity score matching, no significant difference between the UFS and NAC groups (n = 67 for each) was found in long-term outcomes.

Conclusions: NAC for bBR-CRLM did not enhance the prognostic impact of the following liver resection, except for a limited number of optimal candidates experiencing the Biological Conversion.