[Apocrine hidrocystoma associated with gouty tophi of the pinna].

Background: Apocrine hidrocystomas, also known as apocrine cystadenomas, are bening cystic tumours derived from the secretory portion of apocrine sweat glands.
Clinical Case: A 78-year old female was referred to our division for assesment an asymptomatic translucent, well-defined cystic lesion located on the upper helix. The histological features were consistent with apocrine hidrocystoma coexisting with gouty tophi.
Conclusions: We report the second case of apocrine hydrocystoma located in the pinna, outside of ear canal and the first case of its association with gouty tophi described. It is difficult to know which lesion was first established and if the tophi may lead to ductal obstruction and subsequent cystic retention.