Abstract: | A well-differentiated mucoepidermoid carcinoma of the subglottis of a 77-year-old man was studied by light and electron microscopy. The tumor consisted of mucous cells, epidermoid cells, and intermediate cells of both differentiation. Mucous cells formed glands and cystic spaces filled with mucin. Abundant tonofibrils in aggregates were observed in tumor cell cytoplasms when they were differentiated into epidermoid cells. Epidermoid cells varied in differentiation. |