Cryotherapy in extra-abdominal desmoid tumors: A systematic review and meta-analysis

Introduction
Desmoid tumor is a locally-invasive neoplasm that causes significant morbidity. There is recent interest in cryotherapy for treatment of extra-abdominal desmoid tumors. This systematic review assesses evidence on safety and efficacy of cryotherapy in the treatment of extra-abdominal desmoid tumors.

Materials and methods
The systematic review was conducted with reference to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Literature search was performed using MEDLINE and the Cochrane Central Register of Controlled Trials. 9 full text papers were reviewed and meta-analysis was performed for measures of safety, efficacy and symptom relief.

Results
The estimated pooled proportion of major and minor complications was 4.2% (95% CI, 1.8–9.6; I 2 = 0%) and 10.2% (95% CI, 5.7–17.8; I 2 = 0%) respectively. The estimated pooled proportion of non-progressive disease rate of all studies was 85.8% (95% CI, 73.4–93.0; I 2 = 32.9%). The estimated progression free survival rate at 1 year was 84.5% (95% CI:74.6–95.8) and 78.0% at 3 years (95% CI: 63.8–95.3). As for pain control, the estimated pooled proportion of patients with decrease in visual analogue scale (VAS) > = 3 for those with VAS > = 3 before treatment for 2 studies was 87.5% (95% CI, 0.06–100; I 2 = 71.5%) while 37.5% to 96.9% of patients were reported to have experienced partial or complete symptom relief in the other studies.

Conclusion
Cryotherapy is a safe and effective treatment modality for extra-abdominal desmoid tumors with efficacy similar to those treated with traditional strategies in the short to medium term.