One of about 400 patients with ODM followed for life is estimated to develop uveal melanoma. Excessive melanocytes in the uveal tract in ODM may provide the biologic basis for susceptibility to the development of uveal melanoma. Patients with ODM should be monitored ophthalmoscopically, especially during the susceptible period, for the development of uveal melanoma. The authors suggest that a national registry of ODM patients be created and prospective data collected to better assess the risk of developing uveal melanoma.