321 - Cryoablation for Desmoid Tumors: A Single Center Evaluation of Current Treatment Paradigms

Purpose: Desmoid tumors (DT) are rare, locally aggressive neoplasms that can cause significant morbidity despite lacking metastatic potential. Cryoablation (CA) is a minimally invasive therapy that has shown promise for local control, though its role compared with surgery, systemic therapy, and radiation remains uncertain. This study aims to outline our single-center experience, evaluating the relative timing of CA in the treatment of DT and the risk factors associated with tumor recurrence.

Materials and Methods: Following IRB approval, a retrospective analysis was conducted on the institutional sarcoma registry to identify patients with DT who were treated with CA at a tertiary care center. Patient demographics, tumor characteristics, treatment history, procedural data, and oncological outcomes were recorded. Tumor recurrence was defined as clinical progression. Comparative analyses were conducted using the Mann–Whitney U test and Fisher’s exact test, where applicable. All analyses were performed in Python version 3.12.7 (Windows), with a two-sided p-value < 0.05 considered statistically significant.

Results: Seventeen patients (mean age 37.8 ± 9.8 years, 29.4% male, 52.9% Hispanic or Latino) with extra-abdominal (29.4%), extremity (29.4%), and chest wall (29.4%) DT underwent CA. Patients were treated with systemic therapy (94.1%), surgery (37.5%), and radiation (12.5%). Systemic therapy and surgery preceded CA in 82.3% and 11.8% of cases, respectively. The mean time to CA was 3.55 ± 5.15 years. Patients with future recurrence (n=5, 29.4%) underwent CA later in their treatment course (13.1 years) compared with those without recurrence (0.9 years, p=0.001). Mean pre-CA tumor volume was 458.9 ± 536.6 cm³. Procedures lasted a mean of 253.7 ± 159.8 minutes using a median of 5 probes [IQR 2–8] and 2 freeze–thaw cycles [IQR 2–3.5], with mean freeze and thaw times of 27.1 ± 11.1 and 25.1 ± 16.2 minutes, respectively. The mean ablation volume was 252.4 ± 251.4 cm³. Repeat CA was required in 2 patients (11.7%).

Conclusion: CA is an effective second-line treatment for DT, with high local control rates and minimal morbidity. Later use of CA in the treatment course was associated with recurrence, suggesting a potential benefit to earlier utilization. These findings support a growing role of CA in the treatment paradigm, particularly for patients seeking minimally invasive options. Further studies are warranted to refine indications and assess long-term outcomes.