A patient operated for malignant melanoma developed night blindness and a sensation of shimmering light, strong enough to make him unable to work. Shortly afterwards, melanoma metastases became apparent. A full-field ERG examination showed absence of rod responses but normal cone amplitudes, suggesting a malfunctioning rod system in the retina. The patient was not on chemotherapy. A few similar cases have previously been reported. The disease appears to differ from the cancer-associated retinopathy (CAR) syndrome, which affects mainly the photoreceptor cells.