melanotic schwannoma

(redirected from melanocytic schwannoma)

melanotic schwannoma

A rare form of schwannoma characterised by heavy deposition of melanin pigment (Fontana-Masson, S-100, HMB-45, all +ve) linked to melanosomes and premelanosomes. It is often (50% of cases) associated with Carney syndrome (myxomas in various sites, spotty pigmentation, endocrine hyperactivity).

Prognosis
Most melanotic schwannomas behave benignly; they may metastasise.
References in periodicals archive ?
Melanotic schwannoma was first described by Millar (22) in 1932 as a malignant melanotic tumor of ganglion cells, which was subsequently termed melanocytic schwannoma in 1975 by Fu et al.
Non psammomatous melanocytic schwannoma presenting as a subcutaneous nodule: a rare presentation of a rare lesion.
Another entity that needs attention in differential diagnosis is psammomatous melanocytic schwannoma. This entity is seen as a finding of the Carney complex.