What tests do patients need to focus on in between chemotherapy sessions? The most important one is the white blood cells. White blood cells are related to the patient’s ability to fight infections. The current environmental conditions are poor, and if the patient has chronic respiratory diseases or bad habits such as smoking, the decrease in white blood cells can easily induce infections; in addition, we should pay attention to the red blood cell values to prevent anemia, which can affect the effect of chemotherapy. If patients become anemic, they need to adjust their diet, increase the blood supplementation drugs, and even transfusion in serious cases; platelet decline should also be paid extra attention. Patients with declining platelets are prone to bleeding, such as coughing up blood, blood in the stool, stomach bleeding, and in severe cases, possibly brain bleeding. Platelet drop comes after white blood cell drop, but there are limited medications available to raise platelets and platelets do not rise as fast as white blood cells after medication, so platelet values also need to be focused on. Are there any symptoms of declining white blood cells? Can patients feel it themselves? The most common symptoms are malaise, anorexia, lethargy, and fever. When a patient has significant weakness, heavy eyelids or even reluctance to get up, he or she needs to come to the hospital immediately for a blood test because the patient’s blood count may be at its lowest at this time and requires prompt treatment by the doctor. When the patient has fever symptoms, it indicates that the anti-infection ability is reduced and the potential foci of infection in the body can easily induce the disease again. Therefore, when the patient has the above symptoms, it is better to go to the hospital for blood tests.