Metastatic choroidal melanoma to the contralateral orbit 40 years after enucleation

Metastatic uveal melanoma to the contralateral orbit is extremely rare, with only eight cases in the literature having been reported. We reviewed the clinical presentation, the histologic findings of the primary and secondary tumors, and the clinical outcome of these cases and studied an additional case of metastatic choroidal melanoma to the contralateral orbit that occurred 40 years after enucleation for the primary tumor. The long interval between recognition of the primary tumor and the appearance of clinically manifest metastatic disease in the contralateral orbit is the longest reported in the literature to date. The histologic features of the tumor cells of the enucleation specimen and those of the orbital metastasis were similar, consisting of spindle-cell type with minimal atypia. Combined use of immuno-phenotyping and electron microscopy substantiated the diagnosis of melanoma.