Neuroendocrine carcinoma of the breast: mammographic features correlated with sonography and histopathological findings

Abstract

The purpose of this study was to describe the X-ray features of the neuroendocrine carcinoma (NEC) of breast to raise the awareness for the disease. The mammography, sonography and clinicopathologic features in a total of 16 cases of pathologically proven breast neuroendocrine carcinoma in Fudan University Cancer Hospital were analyzed retrospectively. All the 16 patients were women with a mean age of 67.3 years old (ranged from 45 to 75 years old). Twelve patients had palpable masses and the other four patients had outflow from the nipple. Pathological diagnosis included endocrine ductal carcinoma in situ (E-DCIS) in 4 cases, E-DCIS with microinvasion in 5, and invasive solid neuroendocrine carcinoma in 7. On mammography, 9 of 16 cases exhibited round or slightly lobulated masses. Five of the 16 cases exhibited irregular or asymmetric opacities. Two of the 16 cases had negative findings. The borders of the 14 masses detected on mammography were vague in 7, partly unclear in 3 and clear-cut in 4 cases. Malignant microcalcification was not found in all cases. The accuracy rates of preoperative qualitative diagnosis for NEC with mammography and sonography were 68.8% (11/16) and 81.3% (13/16), respectively. Given the application of combined mammography and sonography, the accuracy rates could be improved to 87.5% (14/16). A round mass and irregular or asymmetric opacities without malignant calcification are the most frequent appearances of mammography in neuroendocrine carcinoma of the breast. Combination of mammography and sonography may be useful to improve the accuracy of diagnosis and early detection of neuroendocrine carcinoma of the breast.