Neuroendocrine breast carcinoma

Abstract

Neuroendocrine breast cancer (NEBC) is a rare and heterogeneous entity. It most commonly presents a luminal phenotype and a worse prognosis. When diagnosed in an advanced stage, metastasis from another neuroendocrine tumor should be excluded. This case features a premenopausal woman with an oligometastatic breast large cell neuroendocrine carcinoma, estrogen receptor (ER) positive, and human epidermal growth factor receptor 2 (HER2) negative. Since the patient was very symptomatic at the presentation of the disease, chemotherapy was started. Complete radiological response of the metastatic disease was achieved, and the patient was then submitted to radical breast surgery and bilateral oophorectomy. She subsequently underwent radiation therapy. Since then and to date, she has been under endocrine therapy (ET) and a CDK4/6 inhibitor (CDK4/6i), with no evidence of malignant disease. Evidence to guide the choice of treatment for these tumors is currently scarce. In cases with oligometastatic disease, radical treatment should be considered. Given that this entity is rare, its reporting should be encouraged.

CDK4/6 and aromatase inhibitors as first‐line treatment in metastatic high‐grade neuroendocrine carcinoma of the breast: A case report

“…Since the tumor was hormone receptor positive and HER‐2 negative, she was offered, as adjuvant‐like treatment, a combination of CDK4/6 inhibitor with endocrine therapy, tolerating the treatment well and being disease‐free in her last follow‐up. 12 Although our current knowledge regarding therapeutic management of breast NECs is scarce and based mainly on case reports, CDK4/6 inhibitors are being proposed as another potential targeted therapy. 13 Despite the limitations originating from the lack of clinical trials, we must acknowledge that endocrine based treatment has a crucial role in hormone receptor positive breast cancers, including NECs.…”