Tumor-specific growth factor. Specific growth factors are a class of independent substances that are different from other tumor markers. They are composed of 4 small molecules (carbohydrate substances, amino acids, metabolites, etc.). It can stimulate the angiogenesis of malignant tumors and promote the growth of malignant tumors and the proliferation of surrounding capillaries, and with the formation and growth of malignant tumors, they are gradually released into the peripheral blood. The TSGF content in the serum at the early stage of tumor will be significantly increased. This feature makes it an ideal indicator for the early diagnosis of broad-spectrum malignant tumors.