Outcomes and prognostic factors of repeat pulmonary metastasectomy

Information on prognostic factors after repeat pulmonary metastasectomy (PM) is limited, and outcomes after a third PM are not well documented.

A single-institute retrospective study was conducted. Between 2000 and 2020, 68 patients underwent repeat PM for pulmonary metastases from various cancers. Outcomes and prognostic factors for the second PM and outcomes after the third PM were analysed.

This study included 39 men and 29 women. The mean age at second PM was 53.2 years old. The primary tumours were soft tissue sarcoma in 24 patients, colorectal cancer in 19 and osteosarcoma in 10. The interval between the first PM procedure and detection of pulmonary metastasis after the first PM (months) was ≤12 in 37 patients and >12 in 31 patients. At the second PM, 20 patients underwent lobectomy or bilobectomy, and 48 underwent sublobar resection. Complete resection was achieved in 60 patients, and 52 patients experienced recurrence after the second PM. The 5-year relapse-free survival and overall survival rates after the second PM were 27% and 48%, respectively. Multivariable analysis revealed that the interval between the first PM and the subsequent detection of pulmonary metastasis (≤12 months) was a poor prognostic factor for both relapse-free survival and overall survival after the second PM. Seventeen patients underwent a third PM, 3 of whom achieved a 3-year disease-free survival.

Patients with a period of >12 months between the first PM and the subsequent detection of pulmonary metastases showed favourable outcomes and are thus considered good candidates for second PM. A third PM may be beneficial for selected patients.