An encapsulated tumor with organoid pattern of nests of rounded large epithelial like cells with abundant granular or clear cytoplasm. Cell borders are ill-defined. The nests are separated by a network of fibrovascular trabeculae. Some cells show enlarged nuclei but no evidence of mitotic activity. Capsule of tumor looks attenuated in many foci with evidence of invasion by tumor cell nests.
Righ neck mass, suspected carotid body tumor.
Soft tissue fragment measured 2x1.5x1.2 cm, totally embedded.
Rt neck mass, excision biopsy: