Desmoid tumors are noncancerous growths that occur in the connective tissue. Desmoid tumors most often occur in the abdomen, arms and legs. Another term for desmoid tumors is aggressive fibromatosis. Some desmoid tumors are slow growing and don't require immediate treatment.  The cause of most desmoid tumors is unknown and thus they are called “sporadic” or random. Most desmoids have mutations in a gene called beta catenin. A minority of desmoid tumors are caused by mutations in a gene called A denomatosis Polyposis Coli or APC. Aggressive, wide surgical resection is the treatment of choice. Complete surgical excision of desmoid tumors is the most effective method of cure. Desmoid tumors are similar to scar tissue in that they're fibrous. However, they caninvade the surrounding tissue aggressively and be very difficult to surgically remove.Desmoid tumors often recur, even after they've been completely removed.