Presentation
Abdominal discomfort.
Patient Data
Large enhancing oval mass centered in mid/left abdominal mesentery, displacing bowel. Posterior tumoral vascularity.
No metastases.
PATHOLOGY:
Final diagnosis:
Soft tissue mass: desmoid-type fibromatosis.
An immostain for beta catenin shows strong nuclear staining.
Histologic sections of the abdominal mass demonstrate a proliferation of bland spindled to stellate shaped cells arranged in a long weeping fascicles. The spindle cells fail to show significant cytologic atypia. Overall, the morphologic features in conjunction with the presence of beta catenin immunopositivity are consists with desmoid-type fibromatosis.
Case Discussion
Differential diagnosis for this mass: desmoid, sarcoma, GIST, fibrous tumor, lymphoma.
Unlikely to be aggressive or highly malignant given rounded, well-defined shape and no metastases.
Ultrasound-guided biopsy was performed with final pathology desmoid. This was likely sporadic or related to prior childbirth.