Squamous carcinomas with glandlike (adenoid) features.

Squamous cell carcinomas with a prominent glandlike histologic component are uncommon histologic variants found in the skin and mucous membranes. Although not restricted to the head and neck, they have a predilection for that anatomic area. Lost in the debate over their histogenesis are repeated observations that the carcinomas have an aggressiveness and life-consuming capacity that exceed those of conventional squamous cell carcinomas.