Fig. 2.

ALES tumor cells were monomorphic with predominant round cell (A) or basaloid morphology (B). Peripheral palisading was conspicuous in some tumor islands; the arrow highlights abrupt squamous differentiation (C). Follicle-like spaces filled with pale eosinophilic fluid were identified within the tumor nests and sheets in the nasal (D) and the parotid (E) tumors. Solid nests of tumor cells were admixed with follicles displaying variably thick collars of neoplastic cells replacing normal thyroid follicular cells in a clinging pattern while retaining luminal (colloid) secretions (F)