We present 2 cases of invasive extramammary Paget disease occuring in the vulva area of a 60 year old female, and in the scrotal and penile area of a 63 year old male patient.
The histologically typical Paget cells were not only seen in the surface epithelium but were also involved in the outer root sheath of the hair follicles. Stromal infiltration of tumor cells into the upper dermis were present in both cases, however, no underlying primary sweat gland carcinoma was present. Metastatic foci of inguinal lymph nodes showed apocrine-type epithelium with abundant eosinophilic granular cytoplasm, which were positive for anti-CEA and GCDFP-15, as well as eccrine-type epithelium containing mucinous secretory materials in the lumen and the cytoplasm.
Ultrastructural findings showed interdigitating plasma membranes with prominent desmosomes between the Paget cells, intracytoplasmic tonofibrils, intracellular tubules, lipid vacuoles, and enlarged mitochondria. Histological, immunohistochemical, and ultrastructural findings suggested that Paget cells showed both eccrine and apocrine differentiation.