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Prognostic Factors for Pulmonary Metastasectomy for Colorectal Cancer: A Propensity Score Matching Analysis
Shoji Okado1, Shota Nakamura2, Minoru Sugihara3
1Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Background/Aim:
This study aimed to investigate prognostic factors in pulmonary metastasectomy for colorectal cancer (CRC), considering the location of the primary tumor.
Patients And Methods:
We collected information from patients who underwent pulmonary resection for CRC at two high-volume centers from January 2010 to December 2023. Using a multivariate Cox proportional hazards model, patient background factors that affected the prognosis after pulmonary metastasectomy were identified.
Results:
A total of 289 patients were included in the study. The multivariate analysis revealed the primary tumor site [hazard ratio (HR)=1.89, p=0.016], the maximum diameter of the pulmonary nodule (HR=1.76, p=0.016), and multiple metastases (HR=2.10, p<0.001) had significant prognostic impact on overall survival (OS). The multivariate analysis of disease-free survival (DFS) revealed smoking history (HR=1.58, p=0.039) and multiple metastases (HR=2.08, p<0.001) as significant prognostic factors. After 1:1 propensity score matching (PSM) of patients based on the number of metastatic tumors, two populations revealed a consistent trend with 5-year survival rates of 73.4% and 48.0% for single pulmonary and multiple metastases.
Conclusion:
Multiple metastases significantly worsened both OS and DFS after pulmonary metastasectomy, and the similar trend was observed after PSM.
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