Primary neuroendocrine tumour of the breast: a case report and review of the literature

Abstract

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.

Dramatic response to cyclin D–dependent kinase 4/6 inhibitor in refractory poorly differentiated neuroendocrine carcinoma of the breast

“…6 Another reported case of neuroendocrine carcinoma of the breast expressing estrogen receptor, progesterone receptor, and Her2 achieved remission using docetaxel, trastuzumab, and carboplatin. 7 Because most neuroendocrine breast tumors are estrogen receptor and progesterone receptor positive, endocrine-based therapy may be an effective treatment strategy. Tamoxifen as sole therapy as well as adjuvant treatment after surgery has shown good outcomes.…”

Pierwotne guzy neuroendokrynne piersi, opis czterech przypadków

“…Primary neuroendocrine breast tumours are extremely rare, with no typical clinical symptoms, and the diagnosis of the primary tumour is always done by exclusion [4]. Older women, in their 60s and 70s, are more affected, commonly one decade later than invasive breast cancer [10].…”

“…The primary neuroendocrine tumours of the breast were not separately classified by the WHO until 2003 and account for 0.1% [4] to 5% [5,6] of breast tumours and approximately 1% of all neuroendocrine tumours.…”

“…According to the WHO modification from 2012 [7,8], neuroendocrine tumours are divided into the following groups: well differentiated, poorly differentiated (small cell), and cancers with neuroendocrine differentiation [4]. A local accumulation of neuroendocrine cells is present in many sub-types of breast cancers [9].…”

“…The differentiation between primary and secondary neuroendocrine carcinoma of the breast is possible only after the other primary site is excluded [4].…”