A 34-year-old woman reports a single episode of blood-stained nipple discharge from one breast. Examination reveals a small, discrete subareolar nodule. Excision biopsy shows arborizing papillary fronds composed of fibrovascular cores covered by a double layer of cuboidal to columnar cells within a dilated duct. What is the most likely diagnosis?

• A Solitary intraductal papilloma ✓
• B Encapsulated papillary carcinoma
• C Juvenile fibroadenoma
• D Ductal carcinoma in situ, papillary pattern

Explanation

Solitary intraductal papilloma is the classic cause of serosanguineous nipple discharge in a premenopausal woman and presents as a small subareolar lesion. It consists of papillary fronds with a benign two-cell layer (epithelium plus myoepithelium) on fibrovascular cores. The presence of a preserved myoepithelial layer distinguishes it from papillary carcinoma, which lacks myoepithelial cells and occurs in older women.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.