Hydrocystoma

Alternative names: sweat cyst; Moll gland cyst (apocrine); “Robinson type” (multiple eccrine).

First description: multiple eccrine hidrocystomas described by Robinson (1893) ; the apocrine (cystadenoma/hidrocystoma) delineated by Smith & Chernosky (1974) .

Epidemiology: Middle-aged and older adults; female predominance in multiple eccrine forms; periocular facial location; rare orbital/conjunctival/caruncular involvement. Exacerbated by heat/humidity (seasonality).

Syndromic associations (red flag): multiple periocular apocrine lesions may be a marker of Schöpf–Schulz–Passarge syndrome (SSPS) (ectodermatosis) and, more rarely, of Goltz-Gorlin related forms.

Codes:

• ICD-10-CM: Cysts of eyelid H02.821–H02.824 according to eyelid/half-face; oncological alternative by periocular cutaneous site D23.11–D23.12.

• ICD-11: EK70.3 (Hydrocystoma) .