Enlargement of melanocytic iris lesions.

We evaluated the natural history of 175 melanocytic lesions (nevus or melanoma) of the iris which were managed initially by observation without surgical intervention. Only eight of the 175 lesions (4.6%) enlarged during a median follow-up interval of 3.9 years. Univariate Cox regression analysis revealed that tumor location in the medical portion of the iris (P = 0.047) and pigment dispersion from the lesion onto the adjacent iris and trabecular meshwork (P = 0.056) were the only significant clinical conditions predictive of tumor enlargement. Based on these findings, we recommend conservative management of most melanocytic lesions of the iris.