This document discusses newer tumor markers that can be used for cancer diagnosis, prognosis, and monitoring treatment. It describes various types of biochemical entities that serve as tumor markers, including nucleic acids, proteins, sugars, lipids, and whole tumor cells. Specific examples of tumor markers are discussed, such as enzymes, hormones, oncofetal antigens, tumor-associated proteins, carbohydrate antigens, and genetic markers. The ideal properties of tumor markers and their clinical applications are also summarized.