Comparison of signs of choroidal melanoma spreading into the retina according to optical coherenct tomography and pathomorphological studies

Abstract

The most common factors determining the unfavorable choroidal melanoma (CM) prognosis are: patient's advanced age, tumor size, epithelioid histotype, developed vascularization and extrascleral tumor extension. Also, there are indications ofan unfavorable vital prognosis when hemorrhages appear in the tumor area. There are suggestions that retinal changes detected by optical coherence tomography (OCT) are comparable to the results of morphological studies, and the structure of the choroid determined by EDI-OCT (enhanced depth imaging) matches its morphological structure. Purpose: to assess the possibility of in vivo detection of morphological signs of CMspreading into the retina according to OCT data. Materials and methods. 5 CM patients aged 55.20 ± 10.57 who subsequently underwent primary enucleation, were tested by OCT that showed the maximum CM elevation of 4.85 ± 1.76 mm, and the maximum diameter of13.09 ± 4.14 mm. Results. The correlation of tomographic and histological picture was obtained in the following signs: destruction of Bruch's membrane, presence of hyperreflective changes at the level of retinal pigment epithelium (deposits and extended areas of its thickening), photoreceptors changes, neuroepithelial detachment, the intraretinal cavities. A partial correlation took place for signs of subretinal transudate and infiltration of the outer layers of the retina. No correlation was obtained for the signs of infiltration of inner retina layers and the inner limiting membrane rupture with CM dissemination on a retinal surface. The cases of divergent interpretation between OCT and morphological studies are as­ sociated with the presence of fibrosis foci due to a formation of superficial tumor necrosis and foci of proliferation of the pigment epithelium with its dissemination into the inner retina layers. Conclusion. Comparison of OCT signs ofM C with pathomorphological data obtained from 5 enucleated eyes made it possible to expand the interpretation of OCT signs of CM spreading beyond the Bruch's membrane with the forma­tion of tumor growth zones in the retina.