FINE-NEEDLE ASPIRATION CYTOLOGY OF SMALL-CELL NEUROENDOCRINE CARCINOMA OF THE BREAST - A CASE-REPORT

BACKGROUND: Neuroendocrine tumors, usually small cell (oat cell) carci nomas, are almost always primary in the lungs and are highly malignant . Similar tumors have recently been described to occur in various extr apulmonary sites, such as the uterine cervix and prostate. We report a primary neuroendocrine carcinoma of the breast in a female first diag nosed by fine needle aspiration biopsy (FNAB). Search of the literatur e revealed only three other reports of small cell carcinoma of the bre ast, one in a male and two in a female, thus making this the third doc umented case of neuroendocrine carcinoma of the breast in a female. CA SE: A 45-year-old, black female presented with a firm, nontender mass at the tail of her left breast. FNAB showed atypical epithelial cells with pale nuclei and inconspicuous nucleoli. An excisional biopsy perf ormed one week later showed microscopically it predominantly solid and syncytial pattern of small cells that appeared spindly in places. It had a high mitotic count, and the stroma was rich in lymphocytes and p lasma cells. Immunohistochemical and ultrastructural studies confirmed the diagnosis. CONCLUSION: Small cell (neuroendocrine) mammary carcin oma is a rare entity but does occur and can be diagnosed by FNAB. It d oes not differ essentially from other mammary neoplasms with regard to prognosis.