Comparison of prognosis after enucleation vs cobalt 60 irradiation of melanomas.

Between December 1962 and May 1979, growth of choroidal and ciliary body melanomas was documented in 34 patients prior to enucleation. Twenty-seven of the 34 patients underwent enucleation during the same time period (1967 through 1976), when primary treatment with a cobalt 60 episcleral plaque was employed in a nonrandomized fashion in 21 patients with similar-sized melanomas. Comparison of these two groups of patients, none of whom was unavailable for follow-up and all of whom were followed up for a minimum of 66 months, showed that the probability of dying of metastatic melanoma within five years after cobalt 60 therapy was 50% compared with 16% after enucleation. Factors of potential importance in explaining this difference included nonrandomization, small number of patients in both groups, and greater frequency of anterior location of tumors in the cobalt 60 group (76% vs 22%). A randomized, controlled clinical trial is required to determine the relative safety of treatment for uveal melanomas.