(papillary hidradenoma) is a
benign tumour and was previously regarded as an apocrine tumour.
some authors this tumour is a variant of apocrine adenoma with specific
Now there is
increasing evidence to suggest that it is closely related to the
recently described mammary-like anogenital glands.
Almost always located in the vulval or perianal regions. Ectopic lesions
have been reported on the face, scalp, eyelid, auditory canal and arm.
The tumour usually occurs in middle aged women as small nodules (1cm or less
Histologically, these are circumscribed solid or partly cystic tumour
containing papillary and glandular areas.
There are two types of epithelium
- tall columnar cells with pale eosinophilic cytoplasm and underlying
myoepithelial cell layer.
changes are noted in areas.
Mitotic count is
diastase-resistant granules are present in the apices of the large
The differential diagnosis includes adenocarcinoma.