BASALOID-SQUAMOUS CELL-CARCINOMA OF THE HEAD AND NECK - CLINICOPATHOLOGICAL FEATURES AND DIFFERENTIAL-DIAGNOSIS - DISCUSSION

Basaloid squamous cell carcinoma is a recently recognized variant of s quamous cell carcinoma. The lesion is histologically distinctive and m anifests a predilection for the supraglottis, pyriform sinus, and tong ue base. The immunohistochemical profile is discussed. The differentia l diagnoses include adenoid cystic carcinoma, small cell neuroendocrin e carcinoma, basal cell adenocarcinoma, adenosquamous carcinoma, squam ous cell carcinoma, spindle cell squamous carcinoma, mucoepidermoid ca rcinoma, and adenoid squamous cell carcinoma. Basaloid squamous cell c arcinoma is a biologically high-grade tumor with a propensity for noda l as well as systemic metastases. It is a morphologic and phenotypic e ntity with a separate prognostic significance.