Occult neoplastic epithelial proliferations identified in 4 nipples (Table 1) included primary disease with 1 case of lobular carcinoma in situ involving TDLU in the nipple (Figure 2, A) and 1 case of Paget disease with lesion measuring 0.1 cm (Figure 2, B); and extension of underlying malignancy with 2 cases of pagetoid spread of spatially remote invasive ductal carcinoma (IDC) along lactiferous ducts (Figure 2, C and D).
In a recent report, Paepke et al (16) described their successful experience with NSM in patients with retroareolar tumors by performing careful dissection of lactiferous ducts proximal to the nipple.
Papillomas typically occur in major lactiferous ducts and develop within the wall of the duct.
Papillomas are discrete benign papillary tumors that develop from the epithelium of the lactiferous ducts. They often have a cystic component, which may contain clear fluid, blood, or clot, which formed as a consequence of ductal dilatation.
Papillary lesions of the breast include the spectrum of benign, high-risk, and malignant pathologies and, thus, may involve major or smaller lactiferous ducts. An understanding of the range of pathologic entities will aid the radiologist in considering these lesions on imaging studies.
Microscopic sections from both right and left nipples showed LCIS involving lobules with pagetoid spread into lactiferous ducts. No intraductal or invasive duct carcinoma was found in either nipple.
(7-9) This report describes a unique case of synchronous bilateral Paget disease of the nipple derived from LCIS, which involved underlying lactiferous ducts and lobules in the nipple.