To identify clinical and imaging variables associated with symptomatic recurrence of osteoid osteomas (OO) treated with CT-guided radiofrequency ablation (RFA).

Patients with OO treated with CT-guided RFA at our institution from July 2005 to December 2016 were included in this retrospective study. Clinical data (i.e. patient age, gender, race, clinical follow-up) was collected from available electronic health records. Imaging variables (i.e. tumor dimensions, bone type, sclerosis, etc.) were collected via radiology reports and a blinded review of pre-procedural images was done by a musculoskeletal radiologist. Logistic regression and Kaplan Meier analysis were utilized to identify variables significantly associated with osteoid osteoma recurrence, defined as pain...

63 patients who had undergone CT-guided RFA for OO at our institution with complete imaging reports in our PACS (Agfa, Ridgefield Park, NJ) and APEX electronic health records during the study period (July 2005 – November 2015) were identified and included in the study. Cohort Characteristics: Predominantly young Caucasian males (79%) 54% of OO tumors were located in the femur 78.3% of the tumors were located within the cortex of the bone Mean maximum tumor diameter: 10.2mm Mean tumor volume: 268.6mm3 Eight patients (12.7%) experienced...

This study identifies greater tumor size, the female sex and younger age as potential risk factors for OO recurrence following radiofrequency ablation (RFA).Results also suggest a protective role of thickened cortical bone surrounding OO tumors against post-ablation recurrence, which is one of the few in-vivo accounts of the phenomenon known as the ‘oven effect’. Regardless of tumor size, additional passes of ablation may be warranted for patients with identified risk factors of OO recurrence. Overall, this information is useful in guiding therapy and counseling patients.

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