The management of desmoids in patients with familial adenomatous polyposis (FAP)

Desmoids are rare in the general population but occurs in between 10 to 20% of patients with familial adenomatous polyposis (FAP). This risk is about 852 times the risk for the population at large. Desmoids are benign neoplasms that are capable of infiltrating locally with a high risk of recurrence (25-65%) even after extirpating surgery. Desmoids in FAP may occur extra-abdominally, or within the abdominal wall or most commonly intra-abdominally within the mesentery or retroperitoneal. Desmoids are a major problem in patients with FAP. Mortality from desmoids is high in such patients and ranges from 18 to 31%, compared to peri-ampullary carcinomas at about 22% and cancer in the retained rectum at only about 8%. Simple drug treatment with tamoxifen or NSAIDS like sulindac should be used as first line treatment as it carries a response in 30-50% of patients. Surgery should be reserved for extra-abdominal tumours alone and only when needed. Surgery for intra-abdominal desmoids should really only be attempted for intestinal obstruction or ureteric obstruction. Dacarbazine-Doxorubicin chemotherapy may have dramatic response in some cases. Genetic transfer may unlock this disease in future and may give patients with FAP and severe desmoids hope for the future.