Adult desmoid tumors: biology, management and ongoing trials

PURPOSE OF REVIEW To summarize the current knowledge about the biology and clinical management of adult desmoid tumors. RECENT FINDINGS In the past decade, we have learned that desmoid tumors are driven by alterations of the Wnt/APC/β-catenin pathway, sporadic desmoid tumors are associated with somatic mutations of CTNNB1, and germline mutations of APC and somatic mutations of CTNNB1 are probably mutually exclusive. One-third of desmoid tumors are misdiagnosed; a second pathological opinion is therefore of major importance for desmoid tumor. Surgery is no longer regarded as the cornerstone of desmoid tumors; several retrospective studies have demonstrated the safety of a 'wait and see' policy in sporadic abdominal wall desmoid tumor. Desmoid tumors is no longer regarded as an absolute contraindication for pregnancy. At least two new investigational drugs targeting the Wnt/APC/β-catenin pathway are currently being developed. SUMMARY The management of desmoid tumors requires multidisciplinary expertise by an experienced team. We must fully understand the physiopathology of the disease (factors influencing the natural history of the disease) and learn how to avoid desmoid tumors occurrence in patients with APC germline mutations, identify reliable prognostic/predictive factors and better assess the efficacy of systemic treatment.