Primary Small Cell Malignancies of the Breast: Are They Rare Malignancies?

In contrast with the other organs such as the lung, small cell tumors have been less studied in the breast due to their relatively less frequency. Although rare, neuroendocrine neoplasms, some lymphomas, and some small cell sarcomas such as undifferentiated small round cell sarcoma and rhabdomyosarcoma can be seen in small cell morphology in the breast. Many cytological specimens such as fine-needle aspiration biopsies and touch imprint cytology are used for diagnosis and further prognostic/predictive marker determination in primary breast masses, sentinel and axillary lymph nodes, and metastatic masses. Lobular carcinoma deserves to be considered in the small cell tumor group because of its small, monomorphic, discohesive, scant cytoplasmic cytological features. Since so many different types of tumors in the breast can have small cell characteristics, they should be divided into small cell neuroendocrine tumors and small cell nonneuroendocrine tumors. When evaluating small cell breast tumors cytologically, wide tumor diversity should be kept in mind, and clinical, hematological, and radiological features should be taken into consideration.