Objective: To assess the clinical efficacy of microwave ablation (MWA) in treating tumour patients with postsurgical intrapulmonary oligometastases or oligorecurrence (PIORO).
Study design: Descriptive study. Place and Duration of the Study: Departments of Thoracic Surgery and Oncology, Jinan Central Hospital and Qilu Hospital, Jinan, China, from January 2014 to June 2023.
Methodology: Clinical data of 31 patients with PIORO receiving treatment with MWA were retrospectively analysed. After undergoing MWA, the patients were followed up for computed tomography (CT) examination on the 7th day, 1st month, and every 3 months, respectively. The Kaplan-Meier method was conducted to evaluate the clinical outcomes; overall survival (OS), progression-free survival (PFS), and time to local progression (TTLP).
Results: All patients with PIORO were successfully treated with MWA. The 3-year survival rate of patients was 35.5%. The median OS was 26.0 months, the median PFS was 11.1 months, and the median TTLP was 14.4 months. Patients with oligometastatic or oligorecurrent tumours ≤3 cm in diameter showed better PFS (≤3 cm, 14.261 m vs. >3 cm, 7.786 m; p <0.01) and TTLP (≤3 cm, 19.522 m vs. >3 cm, 12.214 m; p <0.05) than those with tumours >3 cm in diameter. Clinical characteristics of the patients were not significantly correlated with OS.
Conclusion: MWA, as a topically therapeutic method, is an effective procedure for tumour patients with PIORO, especially in cases of oligometastatic or oligorecurrent tumours ≤3 cm in diameter.
Key words: Microwave ablation, Thermal ablation, Oligometastases, Oligorecurrence, Progression-free survival, Survival.