Long-term Outcomes After Resection of Solitary Colorectal Liver Metastases

We aimed to characterize the outcomes of patients undergoing resection of solitary colorectal liver metastases (CLM), including patterns of recurrence and usage of salvage therapy.

A retrospective analysis of 535 consecutive patients who underwent resection of solitary CLM between 1999 and 2021 was performed from an institutional database. Extrahepatic disease and prior liver-directed therapy were excluded. Salvage therapy consisted of repeat resection, ablation, or radiation of all sites of recurrence. Outcomes, overall survival (OS), recurrence-free survival, and hepatic recurrence-free survival were analyzed using time-to-event methods.

The median OS of the whole cohort was 10 years. At a median follow-up of 8.6 years, 52% had recurred at 3 years, 73% of which were at a single site. Salvage therapy was performed in 51% of recurrences and associated with prolonged OS (5.89 [95% confidence interval (CI) 4.68-6.64] years vs. 2.24 [95% CI 1.92-2.41] years; p<0.001). Of those who received salvage therapy, 58% were alive 5 years after recurrence. On multivariate analysis, worse OS was associated with more than three positive lymph nodes in the colon primary (hazard ratio [HR] 2.19 [95% CI 1.56-3.08], p<0.001), tumor size (HR 1.07 [95% CI 1.04-1.1]; p<0.001), and positive margins (HR 1.90 [95% CI 1.07-3.37]; p=0.028). Use of adjuvant hepatic artery infusion chemotherapy was associated with improved OS (HR 0.74 [95% CI 0.54-0.99]; p=0.043) and reduced liver recurrence (HR 0.53 [95% CI 0.37-0.76]; p<0.001).

Patients with resected solitary CLM have excellent long-term survival, with half remaining free of recurrence after initial surgery. In the event of recurrence, repeat salvage treatment is feasible and associated with improved survival.