1.Imaging and serological examination are important auxiliary examinations, but they cannot be used as the basis for final diagnosis. 2. The pathological diagnosis method is: HE staining morphology + immunohistochemistry, and genetic diagnosis and flow cytology for difficult cases. 3.The pathological diagnosis standard is WHO 2001 malignant lymphoma classification standard. 4.Bone marrow aspiration cytology examination is essential. Some lymphomas can be diagnosed based on bone marrow and blood images. Some lymph node biopsies are wrongly diagnosed as lymphoma, but after bone marrow aspiration cytology examination, it is found to be other types of leukemia. 5. Before chemotherapy, blood, urine and fecal routine, liver and kidney function, blood sugar, electrolytes, electrocardiogram, mediastinal CT (chest X-ray if no financial condition), abdominal ultrasound, LDH and LDH3, β2 microglobulin, immunoglobulin and bone marrow examination should be performed. The absence of abnormalities on conventional chest radiographs does not mean that the mediastinal lymph nodes are not enlarged. 6. AnnArbor or Cotswolds staging was applied. Non-Hodgkin’s lymphoma occurring in special tissues and organs can be staged exclusively.