Melanoma-Associated Retinopathy 28 Years After Diagnosis

Abstract

This case report describes the 28-year follow-up of a man diagnosed with melanoma-associated retinopathy when he was in his 30s.

To date, at least 60 case reports of melanoma-associated retinopathy (MAR) have been published, and these patients have the associated autoantibodies targeting epitopes common to melanoma and bipolar cells.¹ The classic symptoms of MAR include flickering and shimmering in the peripheral vision that progresses to constriction of the visual field.^1,2,3 In most MAR cases, the fundus photograph appears normal, and visual acuity and color vision test results are also typically normal.^1,2 These findings create a diagnostic dilemma for the physician. Objective measures of bipolar cell function can be fundamental to making the diagnosis, with on-off responses during electroretinography (ERG) showing a characteristic b-wave depression.⁴ This result can be supported by immunohistochemical analysis, indirect immunoassay, and Western blotting for autoantibodies to bipolar cells⁵; however, although these laboratory tests are used in investigative studies, they have not been established as clinically useful.

Case Description

This case was first reported in 1988, when a man in his 30s reported to his ophthalmologist that he had been experiencing left-eye photosensitivity, visual aura, constriction of the peripheral visual field, and impaired night vision.^2,3 An ERG revealed a decrease in bipolar cell function, which had previously been described in cases of antibodies targeting the retina. This result led to an extensive search for a primary source of cancer that uncovered metastatic melanoma 2 years after the onset of his visual symptoms. He underwent surgical cytoreduction for melanoma. Treatment is generally cytoreduction, chemotherapy, radiotherapy, and intravenous immunoglobulin therapy.⁶ Twenty-eight years later, the patient returned to our clinic for follow-up. His only concern was nyctolopia, worse in the left eye, which had been present and stable since his initial presentation, although it had improved after the treatment for melanoma. An ophthalmologic examination was notable only for lattice degeneration of the retina in his left eye. Follow-up ERG testing showed residual b-wave depression of the on-off response (bipolar cell function) in the left eye compared with the right eye. A comparison with his ERG obtained 28 years earlier showed marked improvements in both eyes (Figure). The on-off responses, however, indicated a persistent deficit in the response of the left eye compared with that of the right eye, which had preserved waveform morphologic features.

Figure. Electroretinogram (ERG) of a Normal Eye, and Initial and 28-Year Follow-up ERGs.

Waveforms from scotopic, photopic, maximal, on-response, and off-response ERG modes are presented. Arrowhead indicates diminished b-wave of the on-response in the left eye. On-response and off-response ERGs were not obtained at initial presentation.

Discussion

Patients with MAR survive a mean of 5.9 years (range, 1-19.5 years).¹ Despite a positive result for the lymph node biopsy performed 28 years earlier, this patient has not shown other signs of metastatic melanoma. Although no enzyme-linked immunosorbent assay was conducted to show autoimmunity to bipolar cells, the patient demonstrated the classic visual symptoms of MAR and visual improvement after melanoma treatment. The visual symptoms in this patient, while improved, still persisted despite treatment. Moreover, the on-off response specific for bipolar cell impairment indicated residual damage to the on-response in the left eye. This case provides a 28-year follow-up in a patient with MAR.