Choroidal cancer is a type of eye cancer that occurs in the choroid, a layer of blood vessels and connective tissue between the retina and the sclera. This cancer primarily affects adults and can lead to vision problems or loss if not detected early. Symptoms may include blurred vision, dark spots in the field of vision, or changes in the appearance of the eye. The most common form of choroidal cancer is melanoma, which arises from pigment-producing cells. Diagnosis typically involves a comprehensive eye examination, imaging tests, and sometimes a biopsy. Treatment options may include radiation therapy, surgery, or laser therapy, depending on the size and location of the tumor.