Primary neuroendocrine tumour of the breast is a rare entity that first appeared in the 2003 World Health Organisation (WHO) classification of breast tumours. The data currently available on its prognosis are contradictory, although it seems clear that histological varieties such as small cell neuroendocrine carcinoma have a worse prognosis, due to their low degree of differentiation. The treatment of choice is surgery, and the indications for chemotherapy or radiotherapy do not differ greatly from those used for other breast tumours. It is crucial to underline the difficulty of establishing treatment protocols due to the low incidence of this histological type.