Small cell epidermoid carcinoma of salivary glands. 'Pseudo'-oat cell carcinoma

Two patients had small cell carcinomas of the salivary glands, with pathological features indicating squamous differentiation, heretofore not described. One is free of disease at seven years, and the second is alive, with regional metastases at four years. Sections from one tumor were studied by electron microscopy and revealed tonofilaments and desmosomes. Most cases of small cell carcinomas of the salivary glands have been considered akin to bronchogenic oat cell carcinoma. Their less aggressive behavior, however, suggests that at least some of these tumors were not true oat cell carcinomas. Our findings, and those of others, indicate that small cell carcinomas of the salivary glands (or head and neck) represent a heterogeneous group. Electron microscopy should be used to determine the exact nature of these neoplasms. If an oat cell nature is ruled out, local and regional treatment should be aggressive, since small cell carcinomas other than oat cell appear not to have a dismal prognosis.