(P 296) PULMONARY CEMENT EMBOLISM ASSOCIATED WITH PERCUTANEOUS CEMENTOPLASTY FOR BONE METASTASIS: MECHANISMS AND PROTECTIVE FACTORS

Objective: Minimally invasive percutaneous cement injection is a valuable palliative technique for managing symptomatic pelvic bone metastases in advanced cancer, offering significant pain relief. However, the risk of pulmonary cement embolism remains poorly understood. This study aimed to identify its mechanisms and potential protective factors to inform safer clinical practice.

Methods: We retrospectively analyzed data from 208 patients who underwent percutaneous cementoplasty for pelvic metastatic lesions between 2008 and 2024. After excluding 50 patients without perioperative computed tomography (CT), 158 were included. We reviewed preoperative factors related to tumor vascularity and intraosseous pressure during cement injection. From 2021 to 2023, a decompression needle was used to maintain intraosseous pressure below 10 kPa. Pulmonary cement embolism was assessed using pre- and postoperative CT imaging.

Results: Pulmonary cement embolism occurred in 20 patients (12.7%). Hypervascular tumors—hepatocellular carcinoma and thyroid cancer—were significantly associated with embolism (p=0.05). Pre-injection radiation therapy showed a protective effect (p=0.02). Intraosseous pressure and other variables were not significantly associated with cement embolism risk.

Conclusion: Pulmonary cement embolism appears to be more closely related to tumor vascularity than to intraosseous pressure during injection. Extra caution is needed when treating hypervascular tumors. Where feasible, radiation therapy prior to cementoplasty may reduce embolism risk and should be considered as a protective strategy.