Abstract
BACKGROUND: No clear guidelines for long-term postoperative maintenance therapy have been established for patients with lung oligometastases from colorectal cancer (CRC) who achieve radiological no evidence of disease after radiofrequency ablation (RFA) treatment. We compared the outcomes of patients with lung oligometastases from CRC after RFA plus maintenance capecitabine with RFA alone. AIM: To determine whether adding capecitabine to RFA improves prognosis compared with RFA alone. METHODS: This multicenter retrospective study included consecutive patients from two tertiary cancer centers treated for pulmonary oligometastases from CRC between 2016 and 2023. Subjects were assigned to RFA plus capecitabine (combined) or RFA alone (only RFA) groups. Primary outcomes included overall survival (OS) and progression-free survival (PFS) survival and the secondary outcome was local tumor progression (LTP). The OS, PFS, and LTP rates were compared between the two groups. In addition, prognostic factors were identified using univariate and multivariate analyses. RESULTS: Combination therapy (RFA + capecitabine, n = 148) and RFA monotherapy (n = 99) were compared in patients with CRC and lung metastases. The median OS was 37.8 months (22.4, 50.3), the PFS was 18.7 months (13.0, 36.5), and the LTP was 31.5 months (20.0, 52.4) in the Only RFA group. The OS increased significantly (P = 0.011) and the LTP decreased at all time points (P < 0.001) in the combined group. The multivariate cox analysis revealed that combined chemotherapy significantly improved OS, with hazard ratios ranging from 0.29 to 0.35 (all P < 0.015) after adjusting for demographic, tumor, and treatment-related factors. The risk of death was consistently lower in the combination therapy group compared to RFA monotherapy. CONCLUSION: RFA prolongs survival and local control in patients with CRC pulmonary oligometastases. Adjuvant capecitabine increases OS and reduces LTP compared to RFA alone, but PFS did not significantly change.