Retinoblastoma (Rb) is a rare form of cancer that rapidly develops from the immature cells of a retina, the light-detecting tissue of the eye. It is the most common malignant cancer of the eye in children, and it is almost exclusively found in young children.

Though most children survive this cancer, they may lose their vision in the affected eye(s) or need to have the eye removed. The man in the picture is Peter Michael Falk, a well-known American actor, who suffered from this form of cancer at an early age. When he was 3 years old, his right eye was removed. He wore an artificial eye for the rest of his life.

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