What's your diagnosis?

A 32-year-old, married, non-promiscuous female presented with extremely itchy, skin-colored lesions over her genitalia for the past two months [Figure 1]. There was no history of menstrual flare or summer exacerbation. The patient had been treated with topical corticosteroids, with no response. Examination of the genitalia revealed multiple, small, skin-colored papules distributed symmetrically over the labia majora. Similar skin lesions were not found anywhere else on the body. The histopathology from one of the papules showed many small ducts lined by two rows of flat to cuboidal cells in the dermis [Figure 2].

Figure 1

Multiple skin coloured papules on vulva

Figure 2

Multiple ducts lined by two rows of flat to cuboidal cells

What's your diagnosis?

Answer: Vulvar Syringomas

Syringomas are benign appendageal tumors of the intraepidermal eccrine sweat ducts, which are seen more commonly in females than in males. They present as multiple, small, firm, skin-colored papules commonly over the periorbital and malar region. More widespread skin lesions have been described involving the chest, abdomen and extremities. Vulvar syringomas may occur as part of generalized skin lesions or rarely, are localized only to the vulva.[1] They are usually asymptomatic and thereby go unnoticed by the patient, however, occasionally vulvar syringomas can be extremely pruritic.[2]

Syringomas may show cyclical changes in their size and symptoms during the menstrual period and pregnancy. The presence of estrogen and progesterone receptors in these tumors shown by immunohistochemistry could explain their cyclical exacerbations.[3-5] The histopathology of the syringomas is diagnostic and includes normal epidermis with dilated, cystic eccrine sweat ducts lined by two rows of epithelial cells, embedded in the fibrous stroma in the dermis. Some of these ducts have comma-like tails, resembling tadpoles.

The diagnosis of vulvar syringomas should be considered in patients with papular lesions on the vulva, vulvar pain syndrome or vulvar pruritus.[6] There are a wide range of conditions which may mimic vulvar syringomas including fox-fordyce disease, steatocystoma multiplex, lymphangioma circumscriptum, senile angiomas, condyloma acuminata, lichen simplex chronicus and contact dermatitis, which can easily be differentiated on histopathology.

The treatment is mainly surgical in the form of excision, electrosurgery, cryotherapy or ablative CO2 lasers. Pruritus if present is troublesome, not controlled effectively by topical corticosteroids and antihistaminics.[1]