Efficacy and safety of C-arm computed tomography-guided microwave ablation with percutaneous osteoplasty for flat bone metastases.

Abstract

Background: Flat bone metastases are common in patients with advanced cancers, often resulting in severe pain, limited mobility, and reduced quality of life (QOL). Traditional treatment options, such as radiotherapy or systemic therapies, often fail to provide sufficient pain relief or improve functional outcomes in these patients. Microwave ablation (MWA) offers advantages, such as shorter procedure times and larger ablation zones, while percutaneous osteoplasty (PO) enhances bone stability and prevents pathological fractures. Despite these benefits, the combination of these techniques for treating flat bone metastases remains underexplored.

Aim: To evaluate the efficacy and safety of C-arm computed tomography (CT)-guided MWA combined with PO for managing painful flat bone metastases, focusing on pain relief, functional improvement, and QOL enhancement.

Methods: A total of 45 patients with refractory moderate-to-severe pain resulting from flat bone metastases who underwent C-arm CT-guided MWA combined with PO between January 2015 and January 2021 were included. The efficacy of the procedure was assessed by changes in the visual analog scale (VAS), Oswestry disability index (ODI), and QOL, as well as the occurrence of complications. Tumor response was evaluated using RECIST v1.1 and mRECIST criteria, with overall response rate (ORR) and disease control rate (DCR) as the primary endpoints.

Results: No serious complications were observed in any of the patients. A significant reduction in VAS and ODI was noted at 1 week, 1 month, and 3 months post-procedure. A marked improvement in QOL was observed at all follow-up points. Bone cement extravasation was observed in 10 patients; however, none exhibited significant clinical symptoms. Based on RECIST v1.1, the ORR was 26.7% and the DCR was 88.9%. The mRECIST evaluation revealed a higher ORR of 51.1% and DCR of 88.9%.

Conclusion: C-arm CT-guided MWA with PO provides a dependable and effective strategy for managing flat bone metastases. It demonstrates significant pain relief, improved functional outcomes, and enhanced QOL. This treatment combination also shows promising tumor response rates with a low complication profile.