The Collaborative Ocular Melanoma Study: an overview

The Collaborative Ocular Melanoma Study (COMS) is a 3-arm study that includes two multicenter randomized clinical trials designed to compare the effectiveness of brachytherapy to enucleation for treatment of medium-size choroidal melanomas, and the effectiveness of enucleation with and without preoperative external-beam radiotherapy for large choroidal melanomas. The third arm is an observational study of small choroidal melanomas. Patient accrual ran from 1987 to 1998.

A review of COMS published reports was conducted.

There is no difference in 5-year all-cause mortality for large- and medium-size choroidal melanomas with COMS-designated treatments. Preoperative radiation for large choroidal melanomas does not improve survival. The accuracy of the clinical diagnosis of choroidal melanoma is excellent.

Data from the trials are still being collected and analyzed, but primary outcomes will unlikely change significantly in the future. Similar rates of mortality after treatment with enucleation and brachytherapy shift the emphasis of selection of therapy to secondary outcomes such as preservation of vision. The findings highlight the need to better understand the biological mechanisms and timing of hematogenous dissemination to achieve an appreciable impact on choroidal melanoma survival.