Primary Small Cell Breast Carcinoma-A Rare Diagnosis: Management Strategies and a Brief Literature Review

Abstract

Neuroendocrine Breast Cancers (NEBC) are reported in approximately 1% of all breast cancers with the small cell variety being the rarest and most poorly differentiated subtype [1]. Although neuro endocrine malignant tumors are frequently of pulmonary origin [2], extrapulmonary sites of this malignancy are reported in most other organs such as the GI tract, trachea ,larynx, bladder, prostate, cervix, ovaries [2]. In the breast, although the exact histogenesis of these tumors is unknown, they are thought to arise from aberrant differentiation of a neoplastic stem cell or less likely derived from neural crest cells that migrate to the breast or originate in neuroendocrine cells of the breast [3] .There are many conflicting reports on the prognosis of NEBC, some reports suggesting that they are less aggressive than the usual invasive ductal carcinoma [4] while others suggest a poorer prognosis [3]. As in invasive ductal carcinoma, high grade, larger tumor size, the presence of lymph node and distant metastasis are associated with poorer prognosis. The small cell subtype of NEBC is however generally associated with a poorer prognosis [5]. As described in our case presentation to follow, specific criteria must be met before a diagnosis of primary small cell breast carcinoma is made, first of all to exclude a lung or other primary source and to confirm that the immunohistochemical features are in keeping with a breast primary.