Desmoid Tumours of the extremity and trunk. A retrospective study of 44 patients

BACKGROUND Desmoid-type fibromatosis (DF) is a aggressive (myo)fibroblastic neoplasm with an infiltrative growth and a tendency to local recurrence. Resection of the tumour and/or radiation were proposed as principal treatment. The aim of this retrospective study was to analyze the local control rates focusing on the effect of surgical margins and radiotherapy. METHODS From 1981 to 2014, 44 patients had been treated. Fifty four therapies had been applied, in 50 cases surgery +/- radiation therapy, NSAIDs or chemotherapy. In 4 cases a conservative approach was chosen. Thirty seven patients had primary, 17 recurrent disease. Endpoint was either local recurrence (LR), progression of residual disease or rare non-metastatic secondary lesions at the same extremity. RESULTS The mean age was 39,4 years. In 17 cases a R0, in 27 a R1 and in 6 cases a R2 resection was achieved. Four patients were treated conservatively. All together in 21 cases radiotherapy, in 5 NSAIDs, in 3 imatinib and in 2 cases each tamoxifen or chemotherapy had been applied. The median follow-up was 119 months. 5-year recurrence free survival after resection was 78%. 10 (20.4%) patients developed LR between 5 and 42 months after therapy. Recurrent disease was a negative factor on LR. Margins, radiotherapy, sex, or size of the tumour had no significant impact on LR. Patients younger than 40 years had a significant higher risk of LR. CONCLUSIONS Surgical margins are less important than keeping function. Radiotherapy might be an option in unresectable lesions, the role of adjuvant radiotherapy is controversially discussed.