A Pilot Study of Intralesional Injection of Triamcinolone Acetonide for Desmoid Tumors: Two-Year Outcomes

The purpose of this pilot study was to examine the clinical efficacy and safety of serial triamcinolone injections for the treatment of desmoid tumors.

Nine patients were enrolled into this prospective study and underwent three serial ultrasound-guided triamcinolone injections (120 mg) at 6-week intervals. MRI was compared at baseline and every 6 months, out to 24 months. Safety and tolerability were assessed by clinical evaluation and questionnaires, including the 12-item short form survey (SF-12), visual analog scale (VAS), and desmoid patient-reported outcome (PRO) tool.

At 24 months, 8 (88.9%) patients demonstrated a reduction in the volume of their tumor while 1 (11.1%) enlarged. Median tumor volume change was -26.9% (-81.1% to 34.6%; P = 0.055) All 9 tumors remained stable based on World Health Organization criteria, whereas 2 (22.2%) demonstrated partial response based on RECIST. There was a significant decrease in the tumor:muscle postcontrast mean signal intensity ratio at 6 months (P = 0.008) and 24 months (P = 0.004). There was a similar decrease in the tumor:muscle T2 mean signal intensity ratio at 24 months (P = 0.02). We found no difference in the SF-12 and VAS scores, but there were significant improvements in the desmoid PRO.

Treatment of desmoid tumors with serial triamcinolone injections appears safe and well tolerated by patients, with a 22% partial response based on RECIST. Further research is needed to confirm our results and determine factors predictive of response.