Radiofrequency Ablation as an Adjunct to Systemic Chemotherapy for Colorectal Pulmonary Metastases

BACKGROUND: Radiofrequency ablation (RFA) is an alternative to local treatment for pulmonary metastases in patients who are nonsurgical candidates. Based on previously documented efficacy of this treatment, the authors retrospectively studied the prognostic factors for long-term survival. METHODS: One hundred patients with unresectable colorectal pulmonary metastases underwent percutaneous RFA. Clinical and treatment variables were collected and evaluated using univariate and multivariate analyses with overall survival as the primary endpoint. RESULTS: At a median follow-up period of 23 (range, 1 to 96) months from the time of RFA treatment, 49 patients have died. The median overall survival after RFA treatment was 36 months and 5-year overall survival rates of 30%. Univariate analyses demonstrated that histopathological grade (p < .001), time to RFA treatment (p = .017), response to treatment (p < .001), repeat RFA treatments (p = .001), presence of extrapulmonary metastases (p < .001), presence of mediastinal lymphadenopathy (p = .007), and adjunct systemic chemotherapy (p < .001) were associated with overall survival. Multivariate analyses demonstrated that response to RFA treatment (p < .001), repeat RFA treatment (p = .002), presence of extrapulmonary metastases (p = .008), and use of adjunct systemic chemotherapy (p = .05) were independent predictors for survival. CONCLUSIONS: Radiofrequency ablation for colorectal pulmonary metastases represents a step forward towards a nonsurgical option of combining systemic and local treatment for metastatic disease and is a safe treatment with a low risk profile. Cancer 2010;116:2106-14. (C) 2010 American Cancer Society.