Progression of infiltrative desmoid tumor following total colectomy in familial adenomatous polyposis
Progressive and tragic case of infiltrative mesenteric desmoid tumor which occurred 5 years following prophylactic total colectomy in a patient with familial adenomatous polyposis (FAP). These patients are at particularly high risk for developing desmoid tumors (especially following surgery), and they are an important cause of morbidity and mortality.
- while many desmoid tumors are round and well-circumscribed, they can also be infiltrative (or mixed well-defined and infiltrative);
- the degree of soft tissue infiltration should not be mistaken for sclerosis mesenteritis which is typically more central and associated with pseudocapsule/fat ring (early mesenteric panniculitis) or retraction and calcifications (later retractile mesenteritis)
- while peritoneal lymphoma or mesothelioma can overlap with this appearance, the lack of adenopathy or peritoneal/serosal implants (and the patient history) can rule these out
- have a high suspicion for abdominal tumors or soft tissue when reviewing imaging for FAP patients; while most commonly intra-abdominal, they can also occur at port sites, body wall, and incisions
- notice the progressive narrowing of mesenteric vasculature, consistent with an infiltrative fibrosing process
- tragically, at the end stage this eroded through the bowel wall and resulted in desmoid-enteric fistula and small bowel obstruction