Prognosis of patients with recurrence after pulmonary metastasectomy for colorectal cancer

Objectives We investigated the prognosis of patients with recurrence of pulmonary metastases (PM) from colorectal cancer (CRC) after resection. Methods We reviewed our surgical series of 101 CRC patients with PM who underwent R0 resection with curative intent. The overall survival (OS) and disease-free survival (DFS) rates after metastasectomy as well as the prognostic factors of survival were analyzed. Results Fifty-five patients (54%) experienced recurrence, of whom 21 had developed extrapulmonary metastasis (EPM) before lung resection. Multivariate analysis restricted to patients with recurrence identified a disease-free interval (DFI) shorter than a year as an adverse prognosticator of OS (HR, 2.68; 95% CI 1.40-5.51; P < 0.01) and DFS (HR, 8.54; 95% CI 3.0-24.6; P < 0.001). EPM was also identified as an adverse prognosticator of OS for patients with recurrence (HR, 3.16; 95% CI 1.64-5.88; P < 0.001). There was a significant difference in the 5-year OS rate between patients with and without EPM (27.9% vs 64.9%, P < 0.001), and between those with a DFI shorter and longer than a year (40.0% vs 75.0%, P < 0.01). Among these, 31 patients (56%) bore lung-limited recurrence after their first lung resection, of whom 20 (36%) underwent a total of 29 repeat pulmonary metastasectomies, which resulted in a 5-year OS rate of 71.3% after the second lung resection. Conclusions Our findings indicate that CRC patients with PM whose DFI is shorter than a year after lung resection or those with prior EPM more frequently experience multisite recurrence.