An irregular firm stellate lesion with white cut surface measuring 20 x 15 x18 mm.
Solid nests of cells, cords and sheets of cells with abundant eosinophilic granular cytoplasm, prominent nucleoli and moderate cellular atypia.
Polygonal, spindle-like cells resting in a hyaline, fibrous stroma.
The cells have distinct borders, small centrally to eccentrically placed nuclei, inconspicuous nucleoli and abundant eosinophilic cytoplasm. B
The cytoplasm contains numerous fine granules as well as scattered larger eosinophilic granules.
There is no evidence of nuclear pleomorphism, multinucleated cells or mitosis.
Stains and Immunohistochemistry
- DPAS positive
- Nuclear and cytoplasmic positivity for S100.
- Cytoplasmic staining for CD68, due to their lysosomal activity.
- Negative for Cytokeratins, HMB45 and Melan-A