TAMOXIFEN-INDUCED CHORIORETINAL CHANGES An Optical Coherence Tomography and Optical Coherence Tomography Angiography Study

Purpose: To study structural chorioretinal changes in tamoxifen-treated patients. Methods: Cross-sectional case-control study comparing structural chorioretinal aspects in tamoxifen-treated patients and healthy controls. Enhanced depth spectral domain optic coherence tomography with choroidal binarization and optic coherence tomography angiography were performed. Individual retinal layer thickness and chorioretinal vascular components were compared. Subgroup analysis regarding history of chemotherapy was performed. Results: Two hundred eyes of 100 TAM-treated patients (Group 1) and 80 eyes of 40 healthy controls (Group 2) were included. Of the 200 spectral domain optic coherence tomography scans from patients, 2 showed structural changes attributable to tamoxifen. Group 1 showed significantly lower values in choroidal parameters and in total retinal, ganglion cell layer, inner plexiform layer, outer nuclear layer, and retinal pigment epithelial thicknesses as well as an increased thickness in the outer plexiform layer. The subgroup not submitted to chemotherapy maintained significant reductions in total retinal thickness, ganglion cell layer, retinal pigment epithelium, outer nuclear layer, outer retinal layer, choroidal parameters, as well as an increased thickness in the outer plexiform layer, in comparison with Group 2. Conclusion: Subclinical structural retinal changes could indicate early retinal pigment epithelial and photoreceptor damage. The new finding of choroidal thinning could point toward another important pathophysiologic process in tamoxifen-induced toxicity.