Abstract:Objective: To investigate the clinical features of neuroendocrine tumor of the breast and its diagnosis and treatment. Methods: The clinicopathologic data of three patients with neuroendocrine tumor of the breast treated in Hunan Provincial People’s Hospital from 2013 to 2017 were retrospectively analyzed. Results: All three patients were female, with age of 31 to 39 years and tumor size of 0.5 to 4.0 cm. Two cases sought medical help for breast mass, and one case for nipple discharge. All cases presented with hypoechoic mass lesion in ultrasound scan. One case underwent modified radical mastectomy, one case underwent nipple-sparing modified radical mastectomy plus primary breast prosthesis reconstruction, and one case underwent simple mastectomy. The pathologic types included solid carcinoma in two cases and small cell carcinoma in one case. Immunohistochemical staining showed chromogranin A (CgA) and synaptophysin (Syn) positive in all the three cases and neuron-specific enolase (NSE) positive in two cases. Patients were followed up for 6 to 32 months, one case died of liver metastases at 6 months after excision, and 2 cases survived with tumor free status. Conclusion: Neuroendocrine tumor of the breast is a rare and special type of breast cancer. Its clinical features and imaging characteristics are usually nonspecific. Pathological and immunohistochemical examinations are considered as gold standard for its diagnosis. The comprehensive treatment with surgical treatment is the main method. Small cell neuroendocrine breast cancer has a poor prognosis.