Adenoma of the nipple, focusing on the contrast-enhanced magnetic resonance imaging findings: report of a case.

A woman in her 50s was referred to our hospital for an investigation of a right breast tumor. The tumor was palpated below the nipple, but there was no erosion or nipple discharge. Mammography showed a well-defined high-density tumor, measuring 2 cm in diameter, without calcification, and ultrasonography showed a low-echoic mass with a fluid component with posterior echo enhancement and a lateral shadow. Contrast-enhanced magnetic resonance imaging (CE-MRI) demonstrated a 1.3 × 0.8 cm solid component and a gradually increasing time-intensity curve. We performed lumpectomy and the pathological findings were adenoma of the nipple. The pattern of the time-intensity curve might be attributed to moderate fibrosis of the tumor. Contrast-enhanced MRI is therefore considered to be very useful in the diagnosis of breast disease because it can show the nature and extent of the breast lesion; however, we should be aware that various patterns have been observed on CE-MRI for adenoma of the nipple.