Blood cancer is clinically called leukemia, which can be divided into acute and chronic. In the initial stage of acute leukemia, there may be sudden high fever, sore throat and bleeding; in the initial stage of chronic leukemia with symptoms, patients may show pale face, weakness, fatigue, enlarged lymph nodes, bleeding and so on. 1. Leukemia is a malignant neoplastic disease originating from the hematopoietic system. Early stage of acute leukemia often presents with sudden high fever, sore throat, swollen and painful gums, cough, diarrhea and other symptoms similar to flu. In addition, bleeding may occur, such as bleeding spots on the skin, nosebleeds, and bleeding gums. Due to disease progression, patients may also develop severe anemia, such as pallor and fatigue. 2. Chronic leukemia starts slowly. Symptomatic patients often show weakness, fatigue, dizziness, loss of appetite, pallor, and may touch enlarged lymph nodes. Some patients may also experience heavy menstrual periods and bleeding that is difficult to stop. Early symptoms of leukemia are often atypical and easily overlooked. When the patient has fever, anemia, bleeding and other symptoms, please consult a doctor in time, under the guidance of the physician to clarify the diagnosis.