The effects of combined microwave ablation and open surgery for the treatment of lung cancer-derived thoracolumbar metastases

Objective To investigate the clinical effects of microwave ablation (MWA) in addition to open surgery for the treatment of lung cancer-derived thoracolumbar metastases. Methods This was a single-institution, retrospective, cohort study. From January 2019 to December 2020, a total of 47 patients with lung cancer-derived thoracolumbar metastases underwent posterior spinal canal decompression and fixation surgery in our hospital. Two independent surgical teams treated these patients. One group underwent open surgery combined with MWA therapy, while the other had open surgery only (control). The pre- and post-operative visual analog scale (VAS) scores and the overall survival (OS) were compared between the MWA and control groups. The Frankel Grade classification was applied for the evaluation of the post-surgical spinal cord function. Improvement was defined as an increase of at least one rank from the pre-operative scores. Each patient was evaluated pre- and post-operatively at 48 h, 1 month, and 3-month intervals. Data on surgical-related complications were recorded. Results Thirty men and 17 women were included, with an average age of 57.9 +/- 11.4 years (range, 26-81 years). Twenty-eight patients underwent MWA and were in the MWA group, and 19 patients were included in the control group. Post-operatively all patients were followed up regularly; the median follow-up time was 12 months (range, 3-24 months), and their median OS was 14 months. Patients in the MWA group had a lower VAS score than those in the control group at the 48-h (1.75 +/- 1.01 vs 2.47 +/- 0.96, P = 0.01) and 1-month (1.79 +/- 0.92 vs 2.53 +/- 1.35, P = 0.048) check-ups. At the 3-month evaluation, the VAS score differences between the two groups were not significant (P = 0.133). After surgery, spinal cord function improvement was not significantly different between the MWA and control groups (P = 0.515). MWA therapy combined with open surgery was not associated with increased OS compared with the control group (P = 0.492). Conclusion MWA can be an effective and safe pain-relief method but may not extend the OS of patients with lung cancer.