Less aggressive treatment for less aggressive disease? A retrospective single-center study of pulmonary-limited metastases associated with colorectal cancer.

OBJECTIVE: To explore the appropriate treatment strategies, clinical outcomes, and prognostic factors of patients with pulmonary-limited metastases derived from colorectal cancer (CRC), usually manifested as a less aggressive course. METHODS: A retrospective review was conducted in 331 CRC patients diagnosed with pulmonary-limited metastases at a single institution between January 2011 and November 2017. The Kaplan-Meier method was used to calculate the overall survival (OS). Further analysis was conducted according to treatment modalities. Univariate and multivariate analyses were used to determine potential prognostic factors influencing OS. RESULTS: With a median follow-up time of 38.6 months, the median OS in all patients was 45.2 months. A total of 163 patients received intensive local treatment with a median OS of 76.4 months, whereas 168 patients received palliative systemic treatment with a median OS of 29.7 months. The median OS was 68.9 months for patients treated with radiotherapy/radiofrequency ablation, with similar efficacy compared to surgery group, whose OS had not reached yet. No survival benefits were observed from the additional targeted therapy in systemic treatment group. The prognostic analysis demonstrated unilateral/bilateral lesions, synchronous/metachronous metastases, intensive local treatment, and resection of primary lesion that were significantly associated with survival of patients. CONCLUSIONS: Intensive local treatment alone for pulmonary lesions was associated with excellent survival in certain patients with CRC presented with metastases confined to lungs. Doublet systemic chemotherapy as the first-line treatment also revealed satisfied efficacy and safety.