To present a case of melanoma-associated retinopathy (MAR) associated with an intranasal melanoma.

A 77-year-old Japanese man visited us complaining of night blindness, blurred vision, and color vision difficulties in both eyes. His best-corrected visual acuity was 0.7 in the right and 1.0 in the left eyes. The rod response of the electroretinogram (ERG) was abolished, and the maximum response had a negative waveform. The a-wave of the single-flash cone response was square shaped, and the b-wave was delayed. The ON-response of the long-flash cone ERG was absent, but the OFF-response was preserved. A severe loss of retinal sensitivity was detected by static perimetry. Positron emission tomography showed no abnormal signs. Six months after the initial examination, an intranasal tumor was detected and surgically removed. The final diagnosis based on histopathology was malignant melanoma.

Our case demonstrates that MAR can be associated with an intranasal mucosal melanoma. Thus, in cases where the primary lesion cannot be identified in patients with MAR-like symptoms and signs, we recommend that preferential sites of mucosal melanomas be examined.