Stage III is divided into stages IIIA, IIIB, and IIIC. In stage IIIC, the tumor (1) has spread to the ciliary body and is size category 4 (more than 18 millimeters wide and may be any thickness; or 15.1 to 18 millimeters wide and more than 12 millimeters thick; or 12.1 to 15 millimeters wide and more than 15 millimeters thick). The tumor has spread through the sclera to the outside of the eyeball. The part of the tumor outside the eyeball is not more than 5 millimeters thick; or (2) may be any size and has spread through the sclera to the outside of the eyeball. The part of the tumor outside the eyeball is more than 5 millimeters thick. The tumor has not spread to the ciliary body.