Case Report: Paraneoplastic melanoma-associated retinopathy mimicking posterior uveitis.

Introduction: Melanoma-associated retinopathy (MAR) is a rare paraneoplastic ocular manifestation of cutaneous or mucocutaneous melanoma. We describe a novel case of MAR that mimicked an inflammatory or infiltrative retinopathy. Patient presentation: A 68-year-old female developed bilateral, painless, floaters over six months with accompanying photopsia. Bilateral posterior uveitis was noted, and bilateral vitrectomies were non-diagnostic for malignancy. A systemic evaluation revealed a subcutaneous lesion on the medial aspect of her right thigh. Biopsy of the lesion was consistent with melanoma. The patient was diagnosed with melanoma-associated retinopathy (MAR). Conclusion and importance: MAR is a vision-threatening paraneoplastic disorder that more commonly arises in patients with an existing diagnosis of melanoma. Most cases of MAR have normal or near normal fundus examinations at onset. Our case is interesting because the fundus presentation mimicked a posterior uveitis and vitrectomy was non-diagnostic. Clinicians should be aware of paraneoplastic MAR and the potential for "masquerade syndrome." Systemic search for underlying neoplasms including occult melanoma or carcinoma is warranted in such cases.