The COMS randomized trial of iodine 125 brachytherapy for choroidal melanoma, III: Initial mortality findings

Objectives: To report initial mortality findings from the Collaborative Ocu lar Melanoma Study (COMS) randomized clinical trial of iodine 125 brachythe rapy vs enucleation for treatment of choroidal melanoma. Methods: Patients were evaluated for eligibility at 43 participating clinic al centers in the United States and Canada. Eligible consenting patients we re assigned randomly at the time of enrollment to enucleation or I-125 brac hytherapy. Patients were examined at specified intervals after enrollment f or data collection purposes. Findings presented herein are based on data re ceived by September 30, 2000. Data for each patient were analyzed with the treatment group to which the patient was assigned randomly at the time of e nrollment. Results: During the 11 1/2-year accrual period, 1317 patients enrolled; 660 were assigned randomly to enucleation and 657 to I-125 brachytherapy. Only 2 patients in the enucleation arm were found to have been misdiagnosed whe n histopathology was reviewed centrally. All but 17 patients (1.3%) receive d the assigned treatment. Adherence to the brachytherapy protocol was excel lent, with 91% of patients treated per protocol. Based on time since enroll ment, 1072 patients (81%) had been followed for mortality for 5 years and 4 16 (32%) for 10 years. A total of 364 patients had died: 188 (28%) of 660 p atients in the enucleation arm and 176 (27%) of 657 patients in the brachyt herapy arm. The unadjusted estimated 5-year survival rates were 81% and 82% , respectively; there was no clinically or statistically significant differ ence in survival rates overall (P =.48, log-rank test). The adjusted estima ted risk ratio for I-125 brachytherapy vs enucleation was 0.99 (95% confide nce interval [CI], 0.80-1.22). Five-year rates of death with histopathologi cally confirmed melanoma metastasis were 11% and 9% following enucleation a nd brachytherapy, respectively; after adjustment, the estimated risk ratio was 0.91 (95% CI, 0.66-1.24). Conclusions: Mortality rates following I-125 brachytherapy did not differ f rom mortality rates following enucleation for up to 12 years after treatmen t of patients with choroidal melanoma who enrolled in this COMS trial. The power of the study was sufficient to indicate that neither treatment is lik ely to increase or decrease mortality rates by as much as 25% relative to t he other.