Primary small cell carcinoma of the vagina arising in a background of atypical adenosis

BACKGROUND: Primary small cell carcinoma of the vagina is rare, with only nine cases published to date. The authors report what they believe to be the first case of primary small cell carcinoma of the vagina arising in a setting of atypical adenosis. METHODS: The tumor was studied by light and electron microscopy and immunohistochemistry. RESULTS: Intracytoplasmic electron-dense neurosecretory type granules were seen, and immunohistochemical demonstration of chromogranin A was documented. CONCLUSIONS: These features were found to be similar to small cell carcinomas arising elsewhere in the female genital tract (i.e., cervix, endometrium, ovary, and vulva).