(P 293) CRYOABLATION FOR EXTRA-ABDOMINAL DESMOID TUMORS: A RETROSPECTIVE STUDY OF RADIOLOGIC AND CLINICAL OUTCOMES

Objective: Desmoid tumors are locally aggressive soft tissue neoplasms with high local recurrence. Image-guided cryoablation has emerged as a minimally invasive treatment option. This study aimed to assess radiologic response, clinical success, and treatment-related complications of cryoablation for extra-abdominal desmoid tumors.

Methods: Patients with desmoid tumors treated between 2020 and 2024 were identified using the Alberta electronic medical record. Those who underwent image-guided cryoablation were included for analysis. The primary outcomes were radiologic response, clinical success, and complications. Radiologic response was assessed using volumetric measurements on contrast-enhanced MRI. Clinical success was defined as no disease progression, no need for additional treatment, and symptom improvement. Repeat cryoablations were allowed.

Results: Of 208 patients with desmoid tumors, 44 (20.7%) underwent cryoablation, and 38 had available data for analysis. A total of 92 cryoablation sessions were performed. Median tumor size was 6.9 cm (IQR 5.5–9.3), and median follow-up was 28.9 months (IQR 14.3–37.3).
Among patients treated exclusively with cryoablation, radiologic response was complete in 27.3%, partial in 57.6%, stable in 12.1%, and progressive in 3.0%. Unplanned repeat cryoablations were performed in 26.3% of patients. The overall clinical success rate was 81.6%. Additional treatment modalities were required in 13.2% of cases following cryoablation.
Complications occurred in 21.1% of patients, with 10.5% classified as Grade ≥3. These included two cases of severe pain, one hemorrhage and one skin necrosis requiring grafting.

Conclusion: Cryoablation is a safe and effective treatment option for selected patients with desmoid tumors, demonstrating favorable tumor control and high rates of symptom improvement. These findings support its role in the multidisciplinary management of desmoid tumors