Malignant melanoma and the central nervous system. A guide for classification based on the clinical findings.

Twenty-seven cases diagnosed as having malignant melanoma affecting the central nervous system have been studied. In 20 patients the tumours represented secondary spread from elsewhere, but there were six who had a primary melanoma either of the spinal cord, leptomeninges, or brain. Confusion exists in the literature about how to differentiate primary from secondary tumours but this suggests several clinical factors which may indicate that the lesion is probably a primary one. This method of categorizing the cases is supported by the differences in duration of symptoms and survival times for each group and a simple classification can therefore be proposed.