Cytomorphology of small-cell (Neuroendocrine) carcinoma on ThinPrep (R) cytology as compared to conventional smears

Small-cell (neuroendocrine) carcinoma of the female genital tract is an unc ommon, aggressive neoplasm that occurs most commonly in the cervix and rare ly in the vagina. Although the cytologic findings have been reported on con ventional smears, the cytologic diagnosis of primary vaginal small-cell car cinoma on ThinPrep(R) material has not been previously reported. We present a case of a 46-yr-old woman who underwent cervical/vaginal biopsies as a r esult of abnormal cells seen on the ThinPrep(R) Pap Test(TM). Small to medi um-sized cells with scant cyloplasm were present singly and in loose, cohes ive clusters. Nuclear molding was noted in a few cellular groups. The diffe rential diagnosis included a high-grade squamous intraepithelial lesion, sm all-cell (neuroendocrine) carcinoma endometrial adenocarcinoma, and lymphom a. Subsequent tissue biopsies with immnnohistochemical staining confirmed a diagnosis of small-cell carcinoma of the vagina. The cytologic features of small-cell (neuroendocrine) carcinoma on slides prepared by the ThinPrep(R ) Pap Test(TM) are discussed and compared to those on conventional cewicova ginal smears. (C) 2001 Wiley-Liss, Inc.