In simple terms, retinoblastoma is an eye cancer that develops in the immature cells of the retina. Though it is rare—with approximately 300 children diagnosed in the U.S. each year—it is the most common eye cancer in children. This malignant intraocular cancer rarely occurs in adults. Retinoblastoma can occur in one or both eyes and is caused by genetic mutations in the nerve cells of the retina. The retina is comprised of nerve tissue and is the part of the eye that’s responsible for sensing...