Definition

A fast-growing type of cancer that usually occurs in the lungs but may also occur in many other parts of the body, such as the cervix, ovary, bladder, prostate, liver, pancreas, and stomach. These cancer cells usually look like small, oval-shaped oats when viewed under a microscope. Oat cell cancer tends to spread quickly to other parts of the body and usually has a poor prognosis (chance of recovery). Also called small cell carcinoma.