Radiofrequency ablation is a valid treatment option for lung metastases: Experience in 566 patients with 1037 metastases
Menée en France sur 566 patients présentant des métastases pulmonaires (âge médian : 62,7 ans ; durée médiane de suivi : 35,5 mois), cette étude met en évidence l'efficacité, du point de vue du taux de contrôle de la maladie à 4 ans, d'une ablation par radiofréquence
Background : Minimal invasive methods are needed as an alternative to surgery for treatment of lung metastases. Patients and methods : The prospective data base of two cancer centers including all consecutive patients treated with radiofrequency ablation (RFA) for lung metastasis over 8 years was reviewed. RFA was performed under general anesthesia, with CT-guidance using a 15-gauge multi-tined expandable electrodes RF needle. Results : 566 patients including 290 men (51%), 62.7 ±13.2 years old with primary tumor to the colon (34%), rectum (18%), kidney (12%), soft tissue (9%), and miscellaneous (27%) received 642 RFA for 1037 lung metastases. 53% of patients had 1 metastasis, 25% had 2, 14% had 3, 5% had 4, 4% had 5 to 8. Metastases were unilateral (75%), or bilateral (25%). The median diameter [extremes] of metastases was 15 mm [4–70]. 22% of patients had extra-pulmonary disease amenable to local therapy including 49 liver, 16 bone, 60 miscellaneous metastases. Median follow-up was 35.5 months. Median OS was 62 months. 4year-local efficacy was 89%. 4 year-lung disease control rate was 44.1%, with patient retreated safely up to 4 times. Primary origin, disease free interval, size and number of metastases were associated with OS in multivariate analysis. Progression at RFA site was associated with poor OS [p=0.011, HR:1.69 (95%CI=1.13-2.54)]. In the 293 colorectal cancer metastases, size >2cm (HR=2.10, p=0.0027) and a number of metastases ≥3 (HR=1.86, p=0.011) remained significantly associated with OS. A prognostic score made of 3 groups based on the 4 above-mentioned prognostic factors demonstrated 3-year OS rates of respectively 82.2%, 69.5% and 53.6% (logrank test, p=<0.0001) among the 3 groups in the overall population, and of 81.3%, 72.8%, and 57.9% (logrank test, p=0.005) in the colorectal cancer patients. Conclusion : Radiofrequency is an option for treatment of small size lung metastases, namely the ones below 2 to 3 cm.