RAPIDLY GROWING CHOROIDAL METASTASIS SIMULATING IMMUNE-RELATED CHOROIDAL ADVERSE REACTION

PURPOSE: To describe a clinical case of a patient with multifocal breast cancer and a choroidal metastasis rapidly growing despite targeted cancer therapy and simulating immune-related choroidal adverse reaction. METHODS: The patient received multimodal imaging including wide-field color fundus photography, spectral domain optical coherence tomography (OCT), ultra-widefield OCT angiography, fundus autofluorescence, fluorescein angiography, indocyanine green angiography. Additionally, MRI imaging and B-scan ultrasonography was performed. RESULTS: A 35-year-old woman with medical history of metastatic multifocal breast cancer on the fifth course of adjuvant targeted therapy with trastuzumab and docetaxel was presented with flickering in the right eye. Fundus examination revealed central flat choroidal lesion with serous retinal detachment. OCT demonstrated a bacillary layer detachment and mild choroidal thickening. After fluorescein angiography and B-scan ultrasonography a Vogt-Koyanagi-Harada-like reaction was suspected. No response was observed after initiation of systemic glucocorticosteroids. The lesion and associated subretinal exudation rapidly progressed for over a month when the lesion demonstrated signs of choroidal metastasis and extraocular metastasis were identified. CONCLUSION: Choroidal metastases can develop despite ongoing systemic cancer therapy as a result of acquired resistance. A rapid growth of choroidal metastasis may simulate Vogt-Koyanagi-Harada-like reaction and requires extensive multimodal imaging and close follow-up.