Optimal therapy for desmoid tumors: current options and challenges for the future.

Desmoid tumors, or aggressive fibromatosis, are rare, locally infiltrative neoplasms caused by mutations that activate β-catenin. Although these tumors do not metastasize, they are difficult to manage due to variability in tumor presentation and behavior. A variety of treatment options exist, including surgery, radiotherapy, chemotherapy, hormone therapy, isolated limb perfusion, cryoablation and tyrosine kinase inhibitors. Treatment-induced morbidity and poor local control rates, combined with spontaneous stabilization of some desmoid tumors, have allowed watchful waiting to recently emerge as a front-line management option. This has emphasized the need to better understand tumor behavior in order to differentiate between tumors that may stabilize and those that may progress. Here, we review the most recent findings in desmoid tumor biology and treatment options for this enigmatic disease.