Fine-needle aspiration of low grade adenosquamous carcinoma of the breast

Low-grade adenosquamous carcinoma is an unusual variant of mammary carcinoma. This malignancy generally presents as a palpable mass without mammographic microcalcifications, and fine-needle aspiration may be the initial technique selected for diagnosis. To our knowledge, the cytologic findings associated with this neoplasm have not been reported. We report a case of low-grade adenosquamous carcinoma of the breast in a 57-yr-old woman, initially studied by fine-needle aspiration cytology and confirmed by excisional biopsy. The aspiration biopsy smears were characterized by low cellularity and small disoriented clusters containing uniform cells of small to medium size. Bipolar cells were not seen in the background. The diagnostic features and differential diagnosis of this unusual neoplasm are reviewed.