Percutaneous image-guided cryoablation of spinal metastases: A systematic review

Percutaneous cryoablation (PCA) is a minimally invasive technique that has been recently used to treat spinal metastases with a paucity of data currently available in the literature. A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Prospective or retrospective studies concerning metastatic spinal neoplasms treated with current generation PCA systems and with available data on safety and clinical outcomes were included. In the 8 included studies (7 retrospective, 1 prospective), a total of 148 patients (females = 63%) underwent spinal PCA. Tumors were located in the cervical (3/109 [2.8%], thoracic (74/109 [68.8%], lumbar (37/109 [33.9%], and sacrococcygeal (17/109 [15.6%] regions. Overall, 187 metastatic spinal lesions were treated. Thermo-protective measures (e.g., carbo-/hydro-dissection, thermocouples) were used in 115/187 [61.5%] procedures. For metastatic spinal tumors, the pooled mean difference (MD) in pain scores from baseline on the 0-10 numeric rating scale was 5.03 (95% confidence interval [CI]: 4.24 to 5.82) at a 1-month follow-up and 4.61 (95% CI: 3.27 to 5.95) at the last reported follow-up (range 24-40 weeks in 3/4 studies). Local tumor control rates ranged widely from 60% to 100% at varying follow-ups. Grade I-II complications were reported in 9/148 [6.1%] patients and grade III-V complications were reported in 3/148 [2.0%]) patients. PCA, as a stand-alone or adjunct modality, may be a viable therapy in appropriately selected patients with painful spinal metastases who were traditionally managed with open surgery and/or radiation therapy.