Abstract
The clinicopathologic and immunohistochemical characteristics of nine cases of
basaloid squamous carcinoma (BSC) of the upper aerodigestive tract are reported,
along with the results of an in situ hybridization for human papilloma virus
(HPV) DNA. The cases were selected through a review of 237 head and neck
carcinomas, and were located in the supraglottic larynx (5), hypopharynx (2),
and the base of tongue (2). The patients were 7 males and 2 females with the
mean age of 62. BSCs were histologically characterized by lobules and nests of
basaloid cells with scanty cytoplasm, comedonecrosis and adenoid features, and
by concomitant presence of squamous cell carcinoma. Immunohistochemically, all
BSCs showed positivity for high molecular weight cytokeratin (HMW CK) with
heterogeneous or diffuse staining pattern, but lacked reactivity for
neuroendocrine markers and bcl-2 oncoprotein. No HPV DNA was detected in BSCs.
This study reaffirms that BSC is a rare carcinoma with a peculiar topographic
distribution and distinct pathologic features.