Desmoid-Type Fibromatosis: Who, When, and How to Treat.

OPINION STATEMENT: Desmoid-type fibromatosis is a sarcoma subtype that gathers some singular characteristics, making it a difficult challenge to face in clinical practice. Despite its excellent survival prognosis, these tumors may be unpredictable, ranging from an asymptomatic indolent course to persistent, local, and extended recurrences that significantly impair quality of life. Although surgery was initially considered the first elective treatment, collected published data during the past few years are now pointing to the "wait and see" approach as a reasonable initial strategy because many patients can live a long life with the disease without having symptoms. When symptoms appear or there is a risk of functional impairment, a wide spectrum of therapies (local and systemic) can be useful in improving symptoms and controlling the disease. Because of the low incidence of desmoid-type fibromatosis, there is scarce scientific evidence supporting any specific treatment. Nonetheless, if volumetric responses are needed, chemotherapy may be a reasonable early option. However, if long-term control of disease is desirable, hormonal therapy, NSAIDs, and TKIs are the likely treatments of choice. Recent new findings in the biologic development of these tumors, such as the role of Wnt/β-catenin dependent pathway, have shown that the prognostic information provided by specific CTNNB1 gene mutations and other genetic profiles can lead to better methods of selecting patients as candidates for other approaches. Based on recent research, the Notch pathway inhibition in DF is one of the most promising potential targets to explore. As an orphan disease, it is mandatory that as many patients as possible be included in clinical trials.