Solitary colorectal liver metastasis: resection determines outcome.

BACKGROUND: Hepatic resection (HR) and radiofrequency ablation (RFA) have been proposed as equivalent treatments for colorectal liver metastasis.

HYPOTHESIS: Recurrence patterns after HR and RFA for solitary liver metastasis are similar.

DESIGN: Analysis of a prospective database at a tertiary care center with systematic review of follow-up imaging in all of the patients.

PATIENTS AND METHODS: Patients with solitary liver metastasis as the first site of metastasis treated for cure by HR or RFA were studied (patients received no prior liver-directed therapy). Prognostic factors, recurrence patterns, and survival rates were analyzed.

RESULTS: Of the 180 patients who were studied, 150 underwent HR and 30 underwent RFA. Radiofrequency ablation was used when resection would leave an inadequate liver remnant (20 patients) or comorbidity precluded safe HR (10 patients). Tumor size and treatment determined recurrence and survival. The local recurrence (LR) rate was markedly lower after HR (5%) than after RFA (37%) (P<.001). Treatment by HR was associated with longer 5-year survival rates than RFA, including LR-free (92% vs 60%, respectively; P<.001), disease-free (50% vs 0%, respectively; P = .001), and overall (71% vs 27%, respectively; P<.001) survival rates. In the subset with tumors 3 cm or larger (n = 79), LR occurred more frequently following RFA (31%) than after HR (3%) (P = .001), with a 5-year LR-free survival rate of 66% after RFA vs 97% after HR (P<.001). Patients with small tumors experienced longer 5-year overall survival rates after HR (72%) as compared with RFA (18%) (P = .006).

CONCLUSIONS: The survival rate following HR of solitary colorectal liver metastasis exceeds 70% at 5 years. Radiofrequency ablation for solitary metastasis is associated with a markedly higher LR rate and shorter recurrence-free and overall survival rates compared with HR, even when small lesions (< or = 3 cm) are considered. Every method should be considered to achieve resection of solitary colorectal liver metastasis, including referral to a specialty center, extended hepatectomy, and chemotherapy.