Impact of microscopic incomplete resection for colorectal liver metastases on surgical margin recurrence: R1‐Contact vs R1 < 1 mm margin width

• Published in: Journal of hepato-biliary-pancreatic sciences Vol. 29; no. 4; pp. 449 - 459
• Main Authors: Ausania, Fabio, Landi, Filippo, Martínez‐Pérez, Aleix, Sandomenico, Raffaele, Cuatrecasas, Miriam, Pages, Mario, Maurel, Joan, Garcia, Rocio, Fuster, Josep, Garcia‐Valdecasas, Juan Carlos
• Format: Journal Article
• Language: English
• Published: Japan Wiley Subscription Services, Inc 01.04.2022
• Subjects: Colorectal cancer; colorectal liver metastases; Colorectal Neoplasms - pathology; Hepatectomy; Humans; Liver Neoplasms; Margins of Excision; Metastasis; Multivariate analysis; Neoplasm Recurrence, Local - pathology; Prognosis; R1 resection; Retrospective Studies; surgical margin recurrence and outcomes; surgical resection; Survival Rate; colorectal liver metastases; R1 resection; surgical resection; surgical margin recurrence and outcomes
• ISSN: 1868-6974; 1868-6982
• DOI: 10.1002/jhbp.1107

Background Several studies highlighted an inferior outcome of R1 resection for colorectal cancer liver metastases (CRLM); it is still unclear whether directly involved margins (R1‐contact) are associated with a poorer outcome compared to R1 < 1 mm. The aim of this study is to analyze the impact on surgical margin recurrence (SMR) of R1‐contact vs R1 < 1 mm patients. Methods Patients who underwent surgery for CRLM between 2009‐2018 with both R1 resections on final histology were included and compared in terms of recurrence and survival. Factors associated with SMR were assessed by univariate and multivariate analysis. Results Out of 477, 77 (17.2%) patients showed R1 resection (53 R1‐Contact and 24 R1 < 1 mm). Overall recurrence rate was 79.2% (R1 < 1 mm = 70.8% vs R1‐contact group = 83%, P = .222). Median disease‐free survival (DFS) and disease‐specific survival (DSS) were significantly higher in R1 < 1 mm vs R1‐contact group (93 vs 55 months; P = .025 and 69 vs 46 months; P = .038, respectively). The SMR rate was higher in R1‐contact compared to R1 < 1 mm group (30.2% vs 8.3%; P = .036). At univariate analysis, age, number of metastases, open surgical approach, RAS status, and R1‐contact were associated with SMR. At multivariate analysis, R1‐contact margin was the only factor independently associated with higher SMR (OR = 5.6; P = .046). Conclusions R1‐contact margin is independently associated with SMR after liver resection for CRLM. Patients with R1‐contact margin will also experience poorer DFS and DSS. It remains unclear whether microscopically involved (R1‐contact) margin status is associated with poorer outcomes than R1 <1 mm margin status for colorectal liver metastases. Ausania and colleagues conclude that an R1‐contact margin is independently related to surgical margin recurrence after liver resection. Patients with R1‐contact margins also experience poorer survival outcomes.