Gene

Neuroendocrine carcinoma

Carcinoma

Biology

Small-cell carcinoma

Prostate cancer

Breast carcinoma

Neuroendocrine tumors

Small Cell Lung Carcinoma

Biochemistry

Hematology

Physics

Optics

Neuroendocrine differentiation

Internal medicine

Hormone

Carcinoid tumour

Oncology

Medicine

Breast cancer

Incidence (geometry)

Cancer

Lung

Phenotype

Pathology

Medical Oncology

Breast carcinoma with neuroendocrine differentiation, also known as neuroendocrine breast carcinoma (NEBC), includes a heterogeneous group of rare tumors, which account for 2–5% of all invasive breast carcinomas. Because of their low incidence, most of the current limited knowledge of these tumors derives from anecdotal case reports or small retrospective series. The diagnosis of NEBC is based on the presence of morphological features similar to gastrointestinal and lung NETs and neuroendocrine markers. NEBCs are usually hormone receptors positive and HER2 negative, but despite this luminal phenotype, most recent studies suggested that NEBC could be associated with worse prognosis compared to invasive breast cancer without neuroendocrine differentiation. Due to its rarity and lack of randomized data, there is little evidence to guide the choice of treatment, so NEBC is currently treated as any invasive breast carcinoma not-otherwise specified. Recently, attempts to molecularly characterize NEBC have been made, in order to provide new targets for a more personalized treatment of this uncommon entity.

Neuroendocrine breast carcinoma: a rare but challenging entity