Minimally invasive techniques for pain palliation in extraspinal bone metastases: a review of conventional methods and cryoablation

Abstract

Minimally invasive techniques are an effective primary or alternative modality for pain palliation in extraspinal bone metastases. Conventional pain palliation therapies consist of chemotherapy, analgesics, and localized radiation therapy, and leave a subset of patients with refractory pain. Minimally invasive techniques include cryoablation, cementoplasty, radiofrequency ablation, selective embolization therapy, laser photocoagulation, ethanol ablation, microwave ablation, and MR-guided focused ultrasound therapy. Cryoablation’s increasing popularity with regard to patients presenting with well-defined osseous pain from lytic or mixed metastases has proven effective with regard to pain relief and narcotic usage decline. Combined with external beam radiation, these effects can be enhanced. Cryoablation is one of many minimally invasive options that may be considered for palliative methods in patients with metastatic axial and appendicular skeletal metastases. Future prospective, randomized trials are much needed to compare the efficacy of these treatments.