FREDERIC B.ASKINMDWILLIAM H.WESTRAMD
The clinical differential diagnosis of a tracheal mass includes nonneoplastic (eg, sarcoidosis and tuberculosis) and neoplastic (eg, hemangioma, chondroma, rhabdomyosarcoma, squamous cell carcinoma, granular cell tumor, and alveolar soft part sarcoma) diseases.1 A biopsy specimen of the mass demonstrated a collection of round cells with a nested growth pattern and vesicular nuclei within the submucosa (Figure 3). High-power magnification of the specimen revealed that the cells had a granular cytoplasm without a distinct cell border (Figure 4). Immunohistochemical studies showed that the tumor cells were postive for S100 protein and negative for cytokeratin.
Diagnosis Pathology Quiz Case 2. Arch Otolaryngol Head Neck Surg. 2002;128(5):594-595. doi: