Assessment of Physician's Systemic Treatment Preferences for Patients with Advanced Desmoid-Type Fibromatosis: Experience-Based Medicine in the Absence of High-Level Evidence

Background: The treatment of advanced desmoid-type fibromatosis (DF) is poorly standardized and primarily based on physician's choice. We assessed systemic treatment preferences for advanced DF among European experts, with the aim to define a control treatment for prospective randomized trials. Material and Methods: A structured questionnaire was sent to a group of physicians involved in DF treatment. Results: 54 experts from 14 countries (Europe, Israel) responded. Disease progression and failure of local therapy were typical indications for systemic therapy. Treatment preferences for patients with sporadic DF versus DF associated with Gardner's syndrome were similar. Physicians use at least 5 different classes of drugs (27 agents). The most frequently used compounds were anti-estrogens and non-steroidal anti-inflammatory agents (NSAIDs), in combination or as single agents. The second and third most common systemic approach was chemotherapy based on methotrexate or an anthracycline. Trial activity was limited to 1 country/1 multicentric study. Conclusions: There is an unmet medical need for evidence-based treatments and well-designed studies. Clinical trials with systemic agents should ideally select a homogeneous DF population with advanced, progressive, ideally symptomatic disease and/or functional impairment after failure of wait-and-see and/or local treatments, and should be randomized, with placebo, anti-estrogens, NSAIDs, or physician's choice as comparator.