Metastatic Cutaneous Melanoma Presenting with Choroidal Metastasis Simulating Primary Uveal Melanoma

Abstract

Purpose: To report a case of metastatic cutaneous melanoma presenting with choroidal metastasis simulating primary uveal melanoma. Design: Case report. Method: Presentation of clinical, radiographic, histopathologic, and tumor genetic findings in a patient with cutaneous melanoma with choroidal metastasis. Results: A 50-year-old man with a remote history of stage 1A cutaneous melanoma presented with eye pain, peripheral vision loss, floaters, red eye, and choroidal mass that was originally diagnosed as a primary uveal melanoma at an outside institution; however, subsequent imaging and clinical evaluation demonstrated that this choroidal mass was the first manifestation of widely metastatic cutaneous melanoma (liver, pancreas, lung, bone, brain, and orbit lesions). Histopathologic analysis of the tumor after enucleation was consistent with cutaneous melanoma, and tumor genetic testing was positive for BRAF V600E mutation, confirming the choroidal lesion to be a cutaneous melanoma metastasis rather than a primary choroidal melanoma. Conclusions: Metastatic cutaneous melanoma to the orbit or globe occurs rarely. Tumor genetic testing may help differentiate metastatic cutaneous melanoma from primary uveal melanoma in cases where the diagnosis is uncertain, and can also inform therapy and prognostic counseling.