Presentation
Lower chest and abdominal wall swellings.
Patient Data
Lower chest wall intramuscular and abdominal wall intramuscular and subcutaneous soft tissue sheets and masses showing mild increased FDG uptake.
Large intra-abdominal left hypochondrial complex cystic/solid mesenteric mass showing large photopenic cystic center and mild FDG uptake of its solid margins. It's abutting the splenic hilum and the gastric body and is displacing the colonic splenic flexure medially.
Smaller solid mesenteric lesions with speculated are seen at the right iliac and umbilical regions.
Pathology of the chest and abdominal wall lesions as well as the intra-abdominal lesion (not shown) revealed fibromatosis (desmoid tumor).
Case Discussion
Fibromatosis can be classified as:
- abdominal wall desmoid fibromatosis
- intra-abdominal desmoid fibromatosis
- extra-abdominal desmoid fibromatosis
The case presents an extensive abdominal wall as well as an intra-abdominal mesenteric desmoid fibromatosis.
Mesenteric desmoids canoccur either sporadically or in association with familial polyposis coli syndrome (FAP): 9-18% of FAP cases may have a desmoid tumor, also they have been commonly associated with estrogen therapy and Gardner syndrome.
On CT, most desmoid tumors are well-circumscribed masses, although in some cases they may appear more aggressive with ill-defined margins. On MRI, characteristic low T2 signal. On PET-CT, it shows low to moderate grade FDG uptake.