Cryoablation in th etreatment of Aneurysmal Bone Cysts. Does it Improve ?Outcome?

Curettage with or without the use of adjuvants is the standard of care in the treatment of an Aneurysmal Bone Cyst (ABC).

The purpose of this study is to compare the outcome of patients diagnosed with an ABC treated by curettage and high speed burr-drilling with and without additional cryo-ablation treated at our institution between the years 2008 and 2014.

All patients treated for an ABC, between January 2008 and December 2014 were included in this retrospective analysis. Patient characteristics, such as age, gender and tumor location, type of treatment, time of follow-up, recurrence rate and functional outcome as measured by the MSTS93 score were noted and compared between the two main treatment options utilized, curettage and high-speed burr drilling versus curettage, high-speed burr drilling and adjuvant cryo-ablation.

In total 50 patients were treated for an ABC during the study period. Five underwent resection/embolization only and were excluded. 18 patients underwent curettage and high-speed burr drilling only (Group A), 27 patients had additional cryo-ablation with a closed Argon/Helium gas system (Group B) for a total cohort of 45 patients.

No statistically significant differences were found between both groups in respect to age, local recurrence, surgical complications and functional outcome. Time of follow-up was significantly longer in the patients treated with cryo-ablation as compared to patients treated with curettage and burr drilling only (41.7 months compared to 26.9 months, p=0.006). Complications that necessitated additional surgery were included one local recurrence, hardware removal in two and infection in another two patients.

Formal curettage with additional high-speed burr drilling achieves excellent tumor control rate with a low complication rate and good functional outcome, without the need for adjuvant treatment.