The simple diagnostic test for cancer has been an elusive Holy Grail that the Galahads of science have pursued for many years. Several procedures have initially shown great promise, but almost all have fallen by the wayside as more meticulous experimentations have disclosed a lack of specificity and an inability to differentiate between normal and oncologic biochemistry. Clinical enzymology has been one of the areas most assiduously investigated. Many biochemists, including the author, felt that because of the nature of the enzyme action, early detection of cancer might be accomplished by the investigation of enzyme activity in body fluids. It was the hope of most clinical enzymologists that there would be a sufficient increment in enzyme levels at the site of origin of the carcinoma so that the changes could be easily detected in the body fluids.