Affiliations: [a]
Department of Interventional Center, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| [b] Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
Correspondence:
[*]
Corresponding author: Bo Zhang, Department of Interventional Center, The Sixth Affiliated Hospital, Sun Yat-sen University, No. 26, Yuancun Erheng Road, Tianhe District, Guangzhou 510655, China. E-mail: zhangb28@mail.sysu.edu.cn.
Abstract: BACKGROUND:Microwave ablation (MWA) is becoming an effective therapy for inoperable pulmonary metastases from colorectal cancer (CRC). However, it is unclear whether the primary tumor location affects survival after MWA. OBJECTIVE:This study aims to investigate the survival outcomes and prognostic factors of MWA based on different primary origins between colon and rectal cancer. METHODS:Patients who underwent MWA for pulmonary metastases from 2014 to 2021 were reviewed. Differences in survival outcomes between colon and rectal cancer were analyzed with the Kaplan-Meier method and log-rank tests. The prognostic factors between groups were then evaluated by univariable and multivariable Cox regression analyses. RESULTS:A total of 118 patients with 154 pulmonary metastases from CRC were treated in 140 MWA sessions. Rectal cancer had a higher proportion with seventy (59.32% ) than colon cancer with forty-eight (40.68% ). The average maximum diameter of pulmonary metastases from rectal cancer (1.09 cm) was greater than that of colon cancer (0.89 cm; p = 0.026). The median follow-up was 18.53 months (range 1.10 – 60.63 months). The disease-free survival (DFS) and overall survival (OS) in colon and rectal cancer groups were 25.97 vs 11.90 months (p = 0.405), and 60.63 vs 53.87 months (p = 0.149), respectively. Multivariate analyses showed that only age was an independent prognostic factor in patients with rectal cancer (HR = 3.70, 95% CI: 1.28 – 10.72, p = 0.023), while none in colon cancer. CONCLUSIONS:Primary CRC location has no impact on survival for patients with pulmonary metastases after MWA, while a disparate prognostic factor exists between colon and rectal cancer.
