[Pathology of the nipple-areola complex : I. Paget's disease of the nipple, variants, and differential diagnoses]. / Pathologie der Mamillenregion : I. Morbus Paget der Mamille, Varianten und Differenzialdiagnosen.

The classical Paget's disease of the nipple is histologically characterized by tumor cell infiltration originating in intraductal or invasive breast carcinoma, immunohistologically by a frequent overexpression of HER2 and clinically by eczema-like changes of the nipple and areola. Variants with different histological, immunohistological, and clinical features are observed in nonclassical forms of Paget's disease, such as isolated Paget's disease of the nipple, anaplastic Paget's disease, Paget's disease with invasion, and pigmented Paget's disease of the nipple. In the differential diagnosis of Paget's disease, benign changes have to be considered, including Toker cell hyperplasia, nipple eczema, and rare dermatoses.

[Pathology of the nipple-areola complex : Part II. Tumors, tumor-like lesions, and supernumerary breast lesions]. / Pathologie der Mamillenregion : Teil II: Tumoren, tumorartige Läsionen und Überschussbildungen.

The nipple-areola complex is the origin of various morphologically distinct tumors and tumor-like lesions, which can be delineated from the special structures of the nipple, in particular the intramammary ducts, skin-appendages, and the intramammary stroma. Benign tumors are most frequent and this includes epithelial tumors such as mammary adenoma and syringomatous tumor of the nipple. Less commonly observed are benign mesenchymal tumors such as leiomyoma of the nipple, or tumor-like lesions like pseudo-lymphoma. With excess formations of the nipple, the different forms of polythelia and polymastia have to be considered.