Background: Microcystic adnexal carcinoma (MAC) is a histologically aggressive appendageal neoplasm that often pursues a beguilingly indolent clinical course. MAC has previously been reported only once in a black patient.
Objective: To present the second MAC ever recorded in a black patient.
Methods: We describe a MAC of substantial dimension occurring in a black patient. The literature was subsequently examined for MAC occurring in ethnic patients.
Results: This MAC is remarkable not only for its occurrence in a black patient, but also because it is one of the largest MACs ever recorded (8 cm), it occurs in a relatively less common site (scalp), and its latency period before diagnosis is the longest ever definitively documented (31 years).
Conclusion: MAC is rare among non-Caucasians. Its relatively indolent clinical growth, especially in sites that are poorly accessible to patient observation, may lead to significant delay in diagnosis and treatment.