Not only local parameters but also genetic determinants like the HLA genes may play a role in the development and clinical behavior of malignant tumors. In skin melanoma the presence of HLA-B40 is associated with a poor prognosis. We tested the hypothesis that the clinical behavior of uveal melanoma is influenced by the HLA type of the patient. The HLA types of 44 patients with uveal melanoma had been determined before operation with a view to using the cornea of the enucleated eye for an HLA-matched corneal transplantation. We compared the ABO and HLA types of the patients with the development of metastases and with the ten-year patient survival. An association was observed between the presence of HLA-B40 and death due to metastasis of uveal melanoma. We conclude that the HLA type of the patient may influence the clinical behavior not only of skin melanoma but also of uveal melanoma.