A case of cutaneous melanoma metastatic to the vitreous cavity: possible pathomechanism and review of the literature

Background Isolated vitreous metastases are extremely rare and the pathogenesis of metastasis is still unclear. Here we present the detailed description of the disease progression in a 68-year-old patient with vitreous seeding of a metastatic cutaneous melanoma beginning at a very early stage. Methods Interventional case report and review of the literature. Results The initial retrohyaloidal metastatic lesion was identified adjacent to a small epiretinal hemorrhage. As the disease progressed golden brown spherules appeared in the posterior vitreous emanating from the area of the lesion. Further progression led to a dense metastatic infiltration of the entire vitreous cavity and a decline of the visual acuity to 20/1200. Diagnostic and therapeutic pars plana vitrectomy was performed to confirm the diagnosis and preserve the eye and useful vision. Conclusions For the first time the formation of vitreous metastases derived from cutaneous melanoma was carefully studied beginning at a very early stage. This made it possible to analyze the rare mechanism of vitreous metastasis, which has not been conclusively known till now. The features of metastatic cutaneous melanoma to the vitreous are discussed in context of a review of the literature that resulted from the study of 17 patients with 22 affected eyes.