Complications following Percutaneous Bone Cryoablation: Retrospective Analysis of 239 Consecutive Patients

Purpose: To report the complication rate and the associated risk factors of bone cryoablation (CA).

Methods and Materials: Complications were assessed retrospectively in 239 consecutive patients undergoing CA of 320 primary or metastatic bone tumors between 2008 and 2017. Common Terminology Criteria for Adverse Events v.5.0 were used to classify complications into major (grade 3–4) and minor (grade < 3). Risk factors affecting major complications that occurred with an incidence ≥ 0.20 were studied by using a multivariate analysis.

Results: The total complication rate was 9.1% (29/320). The major complication rate was 2.5% (8/320). The most frequent major complication was bone fracture (1.2% [4/320]; mean time to fracture was 71 days). Other major complications were infection of the CA site (0.3% [1/320]), tumor seeding (0.3% [1/320]), bleeding (0.3% [1/320], and severe hypotension (0.3% [1/320]).

Common minor complications were postprocedural pain requiring analgesic drugs or injections (2.8% [9/320]), peripheral neuropathy/nerve injury (1.2% [4/320]), and paresthesia (0.9% [3/320]).

Most complications appeared < 24 hours after CA (76% [22/29]).

Associated risk factors included Eastern Cooperative Oncology Group-Performance Status > 2 (odds ratio [OR]: 3.1; 95% confidence interval [CI], 1.3–7.6; p = .01), long bone CA (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 all complications. Age > 70 years (OR: 7.06; 95% CI, 1.6–31.7; p = .03) and use of more than three cryoprobes (OR: 23.6; 95% CI, 2.8–199.0; p = .01) were associated with major complications.

Conclusion: Bone CA is relatively safe. Major complications are more likely to occur in elderly patients when more than three cryoprobes are used. The most frequent major complication is bone fracture that is likely to occur 2 to 3 months within the CA procedure; therefore, immediate consolidation is warranted, ideally in the same interventional session.