A total of 116 patients, all of whom had systemic metastases from posterior uveal melanoma, were evaluated to identify potential indicators for time to systemic metastasis. In the multivariate Cox proportional hazards model with clinically available variables, the age at initial treatment for uveal melanoma, gender and diameter of the primary tumor were revealed to be independent predictive factors for time to systemic metastasis. Age older than 60 years, male gender, and diameter of the primary uveal melanoma more than 10 mm were proved to be independent unfavorable factors. The estimated median time to systemic metastasis for the most unfavorable group (age > 60, male, diameter > 10 mm) was 20.2 months in contrast with 76.1 months for the most favorable group (age < or = 60, female, diameter < or = 10 mm). Although the results of this study cannot be applied to all patients with posterior uveal melanoma, predictive factors for time to systemic metastasis in those patients who have recurred supplement the information obtained from prognostic factors for the likelihood of metastasis or survival. They contribute not only to our understanding of the biology of metastasizing posterior uveal melanoma, but also in developing appropriate strategies for follow-up and treatment.