Histopathologic, immunohistochemical, ultrastructural, and cytogenetic analysis of oncocytic uveal melanoma

The histological findings of malignant melanoma may be highly variable, and the tumor can mimic many other neoplasms. Oncocytic change is defined histologically by abundant, eosinophilic, finely granular cytoplasm due to densely packed mitochondria. Oncocytic change has rarely been described in dermal nevi, meningeal melanocytoma, cutaneous melanoma, or metastatic melanoma. To our knowledge, we give the first description of exclusively oncocytic uveal melanoma.