Hemoglobin (Hb): It is the measure of “anemia”, which is the functional component of red blood cells and plays the role of carrying oxygen to supply tissues, and the normal value for children is 110-140g/L. For children receiving anti-tumor treatment, the level of hemoglobin is usually slightly lower than the normal value due to anemia caused by various reasons. The level of hemoglobin is generally slightly lower than the normal value. After chemotherapy, red blood cells are killed and hemoglobin is reduced. Generally, when hemoglobin is <70g/L, children may show obvious pallor and weakness, and resistance to infection is also reduced, and the symptoms become more and more obvious as the hemoglobin value decreases. He Kejun, Department of Pediatric Hematology and Oncology, Shanghai Xinhua Hospital Platelet count (PLT): Platelets are important members of blood cells involved in blood clotting. The normal range of platelet count is 100-300 (×10^9/L). After intense chemotherapy, platelet counts often drop below 50 (×10^9/L), and the lower the value, the greater the risk of bleeding. When the platelet count is below 20, deep red bleeding spots the size of a pinpoint can be seen on the skin. At the same time, the child is prone to nosebleeds, bleeding gums, even blood in the stool, hematuria, and most frighteningly, intracranial bleeding, which is often fatal. When the platelet count is very low, the doctor will arrange for the child to receive a transfusion of single-collection platelets for supplementation (due to the low stock of platelets, an appointment is needed in advance). C-reactive protein (CRP): CRP can also be measured at the same time as the peripheral blood test. CRP values are generally associated with infections, especially bacterial infections, and can be very high in severe bacterial infections. Therefore, if a child has a fever or some signs of infection, such as cough or diarrhea, it is necessary to bring a CRP test along with the routine blood test to help the doctor determine the type and severity of the infection.