Selective Embolization with N-butyl Cyanoacrylate for Metastatic Bone Disease

Purpose: To evaluate the clinical and imaging effect of selective embolization using N-butyl cyanoacrylate (NBCA) as palliation for bone metastases. Materials and Methods: The procedures and effect of 309 embolizations performed in 243 patients were retrospectively analyzed; 56 patients had repeat embolization at the same location at 1-3 months; 197 patients had embolization for progressive bone metastases after radiation therapy. The mean tumor diameter before embolization was 7.8 cm (range 5-30 cm). In all patients, embolizations were performed under local anesthesia through transfemoral catheterization using NBCA in 33% ethiodized oil. The technical success of embolization was evaluated by angiography after completion of the procedure. The clinical and imaging effect was evaluated at follow-up examinations with a pain score scale and use of analgesics, hypoattenuating areas, tumor size, and ossification. Results: In all 309 embolizations, postprocedural angiography showed complete occlusion of metastatic blood supply and greater than 80% devascularization of the lesions. Greater than 50% reduction of pain score and analgesic doses was achieved in 97% of procedures. The mean duration of pain relief was 8.1 months (range 1-12 months). The mean maximal tumor diameter after embolization was 5.5 cm (range 2-20 cm). Variable ossification appeared in 65 patients. Postembolization syndrome, ischemic pain at the site of embolization, paresthesias, skin breakdown, and subcutaneous necrosis were observed in 87 patients. Conclusions: Selective embolization with NBCA is a safe and effective palliative treatment for metastatic bone lesions of various primary cancers; pain relief is temporary.