Role of thermal ablation in colorectal cancer lung metastases

Background: Consensus guidelines of the European Society for Medical Oncology (ESMO) (2016) provided recommendations for the management of lung metastases. Thermal ablation appears as a tool in the management of these secondary pulmonary lesions, in the same manner as surgical resection or stereotactic ablative radiotherapy (SABR). Methods: Indications, technical considerations, oncological outcomes such as survival (OS) or local control (LC), prognostic factors and complications of thermal ablation in colorectal cancer lung metastases were reviewed and put into perspective with results of surgery and SABR. Results: LC rates varied from 62 to 91%, with size of the metastasis (<2 cm), proximity to the bronchi or vessels, and size of ablation margins (>5 mm) as predictive factors of LC. Median OS varied between 33 and 68 months. Pulmonary free disease interval <12 months, positive carcinoembryonic antigen, absence of neoadjuvant chemotherapy and uncontrolled extra-pulmonary metastases were poor prognostic factors for OS. While chest drainage for less than 48 h was required in 13 to 47% of treatments, major complications were rare. Conclusions: Thermal ablation of a selected subpopulation of patients with colorectal cancer lung metastases is safe and can provide excellent LC and delay systemic chemotherapy.