Serous Retinopathy Associated With Combination MEK and Fibroblast Growth Factor Receptor Inhibitor

Purpose: To present a case of a chemotherapy regimen combining a fibroblast growth factor receptor (FGFR) and mitogen-activated protein kinase kinase (MEK) inhibitor leading to serous retinopathy. Methods: A retrospective chart review of a single case was performed. Results: A 67-year-old man with pancreatic and prostate cancer developed bilateral multifocal pockets of subretinal fluid while on an experimental chemotherapy regimen combining an MEK inhibitor (trametinib) and an FGFR inhibitor (erdafitinib). Conclusions: Given that FGFR lies upstream to the mitogen-activated protein kinase signaling pathway, retinal toxicity may be more severe and more common with FGFR–MEK combination therapy. Future studies are necessary to guide ophthalmic surveillance.