Complications of Percutaneous Bone Tumor Cryoablation: A 10-year Experience.

Background Percutaneous cryoablation has been shown to be effective in the management of painful bone tumors. However, knowledge of the complication rate and risk factors for complication is currently lacking. Purpose To report the complication rate and associated risk factors for bone tumor cryoablation. Materials and Methods This retrospective study reviewed complications in 239 consecutive patients (131 men and 108 women; median age, 64 years; age range, 6-86 years) who underwent cryoablation of 320 primary or metastatic bone tumors between January 2008 and November 2017. Common Terminology Criteria for Adverse Events was used to categorize complications as major (grade 3-4) or minor (grade 1-2). Multivariable analysis was performed for variables with P values less than .20, including age, tumor location, adjacent critical structures, number of cryoprobes, and Eastern Cooperative Oncology Group performance status (ECOG-PS). Results Among the 320 tumors, the total complication rate was 9.1% (29 of 320; 95% confidence interval [CI]: 6%, 12.2%). The major complication rate was 2.5% (eight of 320; 95% CI: 0.8%, 4.2%), with secondary fracture the most frequent complication (1.2% [four of 320]; mean delay, 71 days); cryoablation site infection, tumor seeding, bleeding, and severe hypotension were each observed in 0.3% (one of 320) of procedures. Minor complications included postprocedural pain (2.2% [seven of 320]), peripheral neuropathy (0.9% [three of 320]), and temporary paresthesia (0.9% [three of 320]). For all complications, associated risk factors included ECOG-PS greater than 2 (odds ratio [OR], 3.1 [95% CI: 3, 7.6]; P = .01), long-bone cryoablation (OR, 17.8 [95% CI: 2.3, 136.3]; P = .01), and use of more than three cryoprobes (OR, 2.5 [95% CI: 1.0, 6.0]; P = .04); for major complications, associated risk factors included age greater than 70 years (OR, 7.1 [95% CI: 1.6, 31.7]; P = .01) and use of more than three cryoprobes (OR, 23.6 [95% CI: 2.8, 199.0]; P = .01). Conclusion Bone tumor cryoablation is safe, with a 2.5% rate of major complications, most commonly secondary fracture (1.2%). Major complications are associated with age greater than 70 years and use of more than three cryoprobes. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Jennings in this issue.