Squamous neoplastic component in unconventional squamous cell carcinomas of the larynx

Both otolaryngologists and surgical pathologists are involved in the diagnosis and treatment of lesions of the larynx that are best diagnosed as invasive squamous cell carcinomas of some specified degree of differentiation, not further subclassified (that is, conventional squamous cell carcinomas). On occasion, however, a patient will present with an invasive tumor that on histologic examination diverges from the expected pattern of a squamous cell carcinoma of the usual type and so raises the question of proper classification (on the part of the pathologist) and, following classification, a consideration of the prognostic and therapeutic implications of such a classification (on the part of the clinician). While some of these unconventional squamous cell carcinomas are rather indolent lesions (as, for example, the hybrid verrucous squamous cell carcinoma), others behave in a fashion similar to conventional squamous cell carcinomas (such as the adenoid squamous cell carcinomas), and yet others seem to behave more aggressively than do conventional squamous cell carcinomas of a similar size and stage (examples include the basaloid squamous cell carcinomas and adenosquamous carcinomas). Finally, the possibility exists within the larynx, as elsewhere in the body, that a nonepithelial lesion such as malignant melanoma may mimic a tumor more commonly encountered in that vicinity- namely, a squamous cell carcinoma- and so receive inappropriate treatment if such mimicry is not recognized.