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.