Long-term outcomes of pulmonary metastasectomy: a multicentre analysis.

BACKGROUND Many extrapulmonary neoplasms metastasize to the lungs. We conducted a retrospective review of all patients who underwent pulmonary metastasectomy for oligometastatic disease at two centres in order to determine long-term outcomes. METHODS The study institutions' thoracic surgery databases were searched for all patients who underwent pulmonary metastasectomy from 2000 to 2017. RESULTS There were a total of 476 patients who underwent pulmonary metastasectomy. Mean age at time of surgery was 57.2 ± 15.9 years. Mean number of pulmonary lesions was 1.9 ± 1.6. Mean disease-free interval (DFI) was 3.6 ± 4.3 years. The most common primary neoplasms were colorectal cancer (CRC) in 35.1% (167/476), sarcoma in 23.9% (114/476), melanoma in 16.2% (77/478), renal cell carcinoma (RCC) in 7.3% (35/476) and germ cell tumour (GCT) in 4.4% (21/476). Hospital mortality was 0.4% (2/476). Mean follow-up time was 3.8 ± 2.9 years. Survival was 88.9% (95% confidence interval 85.77-91.5) at 1 year and 49.6% (95% confidence interval 44.4-54.6) at 5 years. On multivariate Cox-regression analysis GCT (P = 0.004), CRC (P = 0.03), DFI of 36+ months (P = 0.007), R0 resection (P = 0.002) and non-anatomical, sub-lobar (wedge) resection (P = 0.002) were protective against mortality. CONCLUSION Pulmonary metastasectomy is associated with survival of 50% at 5-year follow-up. DFI of over 36 months, R0 resections, lesions resectable by wedge resection rather than anatomic resection and GCT and CRC primary cancers were associated with improved survival.