Prognostic Implications of the Largest Basal Tumor Diameter vs the TNM Staging System in Association With the Gene Expression Profile for Uveal Melanoma

To the Editor Walter and coworkers¹ suggest in JAMA Ophthalmology that the prognostic value of gene expression profiling (GEP) could be improved by considering the largest basal tumor diameter (LBD) of choroidal and ciliary body melanomas, which was the only additional independent prognosticator. Stepwise statistical analysis identified 12 mm as the threshold that best separated progression-free survival: when the LBD was below the threshold, class 2 melanomas had a better prognosis, and only 2 of 11 class 1 melanomas metastasized.