Patterns and Predictors of Recurrence After Curative Resection of Colorectal Liver Metastasis (CRLM).

Background: Our study aims to determine the predictors and patterns of relapses after curative colorectal liver metastasis (CRLM) resection.

Methods: A single-centre, retrospective study of CRLM patients operated between 2010 and 2022 was performed. The site of first recurrence was either hepatic (marginal (≤ 1 cm) or extramarginal), extrahepatic, or both. Factors that predicted relapse patterns and overall survival were determined by multivariable Cox regression analysis with backward elimination of variables.

Results: The study consisted of 258 patients, with a similar proportion of synchronous (144; 56%) and metachronous(114; 43%) metastasis. At a 43-month median follow-up, 156 patients (60.4%) developed recurrences with 33 (21.1%) in the liver, 62(24.03%) extra-hepatic recurrences, and 58 (22.48%) having both. Isolated marginal liver relapses were seen in seven (9.89%) liver recurrence patients. The median overall and relapse-free survivals were 38 months (30-54) and 13 months (11-16), respectively. The 3-year liver-relapse-free survival was 54.4% (44.9-60.6). Size of liver metastases > 5 cm (HR 2.06 (1.34-3.17), involved surgical margins (HR 2.16 (1.27-3.68)), and adjuvant chemotherapy (HR 1.89 (1.07-3.35)) were predictors of hepatic recurrences. Node positivity of primary (HR 1.61 (1.02-2.56)), presence of baseline extra-hepatic metastases (HR 0.30 (0.18-0.51)), size of liver metastases > 5 cm (HR 2.02 (1.37-2.99)), poorly differentiated histology (HR 2.25 (1.28-3.49)), presence of LVI (HR 2.25 (1.28-3.94)), and adjuvant chemotherapy (HR 2.15 (1.28-3.61)) were predictors of extra-hepatic recurrences.

Conclusion: The study found majority relapses occurred at extrahepatic sites whilst isolated marginal recurrences were few. The consistent predictors of recurrence were size and inability to deliver adjuvant therapy. A tailored adjuvant therapy might improve outcomes after liver metastasectomy in colorectal cancers.