Malignant transformation of multifocal tapioca iris nevus in a child.

A 31-month-old white boy was evaluated for multiple iris lesions in his left eye, initially suspected to be juvenile xanthogranuloma and later diagnosed as tapioca nevi. Four years later the tumors enlarged. There was invasion throughout the anterior segment into the angle and related secondary elevation in intraocular pressure. Fine-needle aspiration biopsy disclosed spindle-B melanoma. Treatment with custom-designed iodine-125 plaque radiotherapy resulted in tumor regression and stabilization of intraocular pressure.