Metastatic Malignant Melanoma
Ovarian involvement may occur via hematogenous route in patients with disseminated malignant melanoma. Metastases may be detected decades after the excision of the primary lesion. Sometimes, the primary lesion undergoes regression or remains occult even after a thorough search. Primary ovarian melanomas do occur - usually arising in a teratoma - however, they are extremely rare. Metastatic melanoma to the ovary can mimic juvenile granulosa cell tumor or hypercalcemic type small cell carcinoma. Immunostains for S-100, HMB-45, and Melan-A (Mart-1) can be used in challenging cases. All three stains should be positive in melanomas.