Elevated blood calcium has no obvious correlation to the diagnosis of malignant tumors, and has no diagnostic significance, and no amount of elevated blood calcium can generally be diagnosed as cancer. The diagnosis of malignant tumors should be based on physical signs, imaging, cytology, immunology, genomics, pathology and other comprehensive diagnosis, even relatively sensitive blood tumor markers can not rely on a single indicator to diagnose malignant tumors. There are many clinical conditions that can cause elevated blood calcium, such as thyroid disease, which can cause abnormal calcium metabolism. Adrenal disease can cause abnormal calcium metabolism by affecting systemic metabolism. Certain primary bone tumors or metastatic bone tumors can also cause elevated blood calcium. Elevated blood calcium has no practical significance in the diagnosis of cancer. If abnormalities are found, one should go to the hospital in time for diagnosis and treatment under the guidance of professional doctors.