malignancies that have neither metastasized nor invaded beyond the layer of tissue where they arose); 2) locally invasive malignancies; or 3) complex tumors intermixed with other malignancies such as extramammary Paget disease, melanoma, and squamous cell carcinoma. Furthermore, benign papillary hidradenoma tumors may be confused clinically with cancerous tumors and recent studies have indicated that other types of tumors have often been mistakenly diagnosed as papillary hidradenomas. Papillary hidradenomas, particularly ectopic papillary hidradenomas, require further study to better define the criteria for their diagnosis. Presentation
In a review of 264 women diagnosed with anogenital papillary hidradenomas, patients ranged in age from 25 to 82 years (median: 49 years); in 25 cases where the information was available, the tumors had been present for 2–120 months (median: 12 months) with 13 patients reporting their tumors presence for less than 1 year before diagnosis. All patients had a solitary tumor in the anogenital area except for one patient who presented with four clustered tumors. Most tumors involved the vulva (71.6%) and areas around the anus (14%) or space between the anus and vulva, i.e. the perineum (3.8%). Their lesions ranged in size from 0.2 to 2 centimeters (cm.) in largest dimension (median: 0.7 cm.). Smaller studies on one or a few females with anogenital papillary hidradenomas found that the tumors commonly presented as asymptomatic, well-confined, skin-colored, red, or bluish nodules in women of Caucasian origin between the ages of 25–66 years. The nodules were solid or cystic; 0.4 to 2.5 cm.
A papillary hidradenoma, also termed hidradenoma papilliferum or mammary-like gland adenoma of the vulva, is a rare, but nonetheless most common benign tumor that occurs in and between anal and genital regions (i.e. anogenital  area) of females. These hidradenomas are sharply circumscribed, nodular tumors that usually develop in womens anogenital area (particularly the vulva) but uncommonly occur in other sites in women and men. Papillary hidradenomas that develop outside of the anogenital region are termed ecctopic papillary hidradenomas or ectopic hidradenoma papilliferums.Anogenital papillary hidradenomas are regarded as tumors that form in anogenital mammary–like glands (MLAGs); MLAGs are a type of apocrine gland. MLAGs were once classified as abnormally located breast tissue glands (see accessory breast tissue@ https://doi.org/10.53347/rID-11125) but are now considered to be normal components of the anogenital region. Microscopically, papillary hidradenomas often resemble certain types of breast tumors. Ectopic papillary hidradenomas are thought to be tumors of apocrine glands which have an as yet unclear relationship to MLAGs.Typically, papillary hidradenomas are solitary, slow-growing, small tumors that may have been present for months to many years before the time of diagnosis. The tumors are usually symptomless but may be intermittently or constantly painful, become ulcerated, and exhibit minor levels of bleeding. The pain resulting from these tumors may be simple tenderness, more or less constant usually mild pain, or, in females, dyspareunia, i.e. pain during and just after sexual intercourse.Rarely, papillary hidradenomas have progressed to what appear to be 1) in situ malignancies (i.e.