Introduction Desmoid tumours, also known as aggressive deep fibromatoses, are soft tissue tumours. Histologically benign, they are characterised by a slow infiltrative course with a high rate of local recurrence. Patients and methods: We report a retrospective series of 10 patients treated in the medical oncology department of the Pierre & Marie Curie Centre over a period of 4 years. 6 were women and 4 men, with a sex ratio of 1.5 in favour of women. The average age was 36 [23-53]. 20% (n=2) of patients had familial adenomatous polyposis. 90% of patients had an extra-abdominal desmoid tumour compared with only 10% in the abdominal wall. 50% of patients underwent initial resection, 60% of whom recurred after 1 year. Only one patient underwent additional radiotherapy. Initial surveillance was proposed in 50% of patients. 60% progressed after 2 years. Only one patient underwent surgical treatment combined with radiotherapy after an initial monitoring period of 9 years. Treatment with IMATINIB 400mg/d was initiated in 60% (n=6) of patients after progression or local recurrence. One patient received tamoxifen for one year. Results: Lesion stability was observed in 6 patients (60%), a partial response (left scapular) in 1 patient and local progression in 1 patient. Tolerability: Grade 3 neutropenia in 1 patient and Grade 2 liver toxicity. Conclusion : Desmoid tumours are rare tumours which progress slowly and are locally aggressive. Their prognosis is closely linked to their recurrence. The current therapeutic approach advocates a "WAIT AND SEE" strategy, particularly in asymptomatic, non-progressive forms. Surgery is only indicated if the immediate vital or functional prognosis is at risk.