Tissue Culture of Uveal Melanomas

Introduction The histogenesis of uveal melanomas has been debated for years. Their derivation from pigmented cells of the uvea 1 is generally accepted but from which pigmented cells has remained in doubt, and the question has been complicated by lack of precise knowledge of the origin of pigment itself. Many investigators who have considered the choroid as a purely mesodermal structure have called these tumors "melanosarcomas." 2-7 Others have considered them of ectodermal origin, derived from the retinal pigment epithelium, 8,9,10 and the work of Wieting and Hamdi 11 suggests that the uveal pigment itself may arise from this epithelium. Redslob 12 attributed an important role to neuroectodermal cells which he saw migrate forward around the optic stalk, and also around the retinal pigment epithelium, during embryonal life. Posteriorly these same cells form the pia arachnoid sheaths of the optic nerve. For this reason Redslob related uveal melanomas to meningoblastomas.