Abstract
PURPOSE: The aim of this study was to determine outcomes and prognostic factors for patients with primary and locally recurrent extra-abdominal desmoid tumors who underwent percutaneous cryoablation, and to compare with patients treated with surgery. METHODS: Group characteristics were compared using Fisher's exact test, and propensity score matching was performed using the nearest-neighbor approach. Kaplan-Meier and log-rank analyses were used to evaluate the variation in first local recurrence and disease control, while multivariate Cox regression was used to identify factors associated with first local recurrence. All statistical tests were two-sided and a p-value of 0.05 was considered statistically significant. RESULTS: Twenty-two cryoablation patients were matched with 33 surgical patients (n = 55). Median follow-up after cryoablation was 16.3 months versus 14.9 months after surgery. Two-year local recurrence-free survival (LRFS) was 59% after cryoablation and 71% after surgery, and median LRFS was 26.6 months after cryoablation but was not reached after surgery. Two-year disease control for all patients was 85%, however median disease control was not reached in either the cryoablation or surgery groups. There was no significant difference in LRFS or disease control between matched cryoablation and surgical patients. No local recurrences occurred after the first cryoablation in patients with zero or one of the following risk factors: tumor size > 5 cm, age ≤ 25 years, or locally recurrent disease. All patients with two or more of these risk factors recurred locally after the first cryoablation. CONCLUSION: Percutaneous cryoablation of primary and locally recurrent extra-abdominal desmoid tumors provides freedom from first local recurrence and long-term disease control comparable with surgery.