Clinical features and treatment response of solid neuroendocrine breast carcinoma to adjuvant chemotherapy and endocrine therapy.

Solid neuroendocrine breast carcinoma (solid NEBC) is a relatively uncommon malignant tumor of the breast. The purpose of our study was to explore the incidence and clinical features of this tumor, and to evaluate the efficacy of adjuvant chemotherapy and endocrine therapy for patients with solid NEBC. Of 7542 breast cancers registered during the period from March 2004 to April 2011, 22 patients (0.29%) who underwent surgery had tumors that were histologically confirmed as solid NEBC, and were enrolled in this study. The age range of these patients was 29-77 years (mean 52.5 years). Patients were staged according to the 7th edition of the pathologic tumor-node-metastasis (pTNM) staging system. Biopsies or resection specimens were reviewed and reclassified according to the World Health Organization (WHO) 2003 classification. We recorded clinical features including gender and age, chief complaint, and past medical history, tumor characteristics including size, location, preoperative diagnosis, and pathologic and immunohistochemical findings, the therapeutic schedule, and the follow-up results. Solid NEBC is a rare and distinct category of malignant disease of the breast, with good prognosis, and in most early-stage cases, is resectable. The role of adjuvant chemotherapy and endocrine therapy in solid NEBC may be limited and should be studied further.