Cancer is a disease initiated by a series of genetic mutations affecting the intrinsic cellular program, leading to out-of-control cell growth and tissue invasion, variety of substances including cell surface antigens, cytoplasmic proteins, enzymes, hormones, oncofetal antigens, receptors, oncogenes and their products are produced by some cancers or by the body in response to the presence of cancer, these substances are called cancer markers and are specific for a particular tumor. Different tumor marker, their properties, method of estimation and their accuracy in diagnosis of cancer is...