Cytokeratin 19 fragment and CA724 belong to the tumor markers, the elevation suggests the possibility of tumor, if it is a tumor, it is more serious and needs further examination and treatment; if it is caused by apoptosis, it is generally not serious and can be restored to normal after body repair. After the apoptosis of alveolar epithelial cells, the fragments of keratin contained in the cells are degraded and turned into soluble substances as cytokeratin 19 fragment, which is the first choice of marker for NSCLC, with high sensitivity and specificity, and it is of great significance to the monitoring and prognosis judgment of NSCLC. CA724 is a non-specific tumor marker with high sensitivity for gastric cancer, non-small cell lung cancer, ovarian tumors, etc. It is commonly used to detect various gastrointestinal tumors and lung tumors. In addition to tumors, organ damage and apoptosis conditions caused by other reasons can also cause elevated tumor markers, which can return to normal after the body repairs. When cytokeratin 19 fragment and CA724 are elevated, we should be alert to the presence of tumors, and suggest to improve CT, gastroenteroscopy and other related examinations to clarify whether there is a tumor. If it is determined that there is a tumor, it is a serious situation, and surgery and chemotherapy should be carried out in time. If the possibility of tumor can be excluded, the situation is not serious.