Lymphoma is a disease that originates in the lymph nodes and extra-nodal tissues, and when CT is done, it first includes three sites: CT of the head, CT of the chest, and CT of the abdomen. Clinical manifestations are evident when lymph nodes infiltrate the skull, chest, and upper abdomen. In the head, there may be multiple tumors that indicate lymphoma infiltrating the skull. In the chest, small nodules in the lungs and enlarged mediastinal lymph nodes are also considered to be signs of localized lymphoma infiltration. For the abdomen, it is the lymph nodes of the liver, gallbladder, pancreas, spleen, kidney, and retroperitoneum. Lymph node infiltrations tend to grow by leaps and bounds, so there will be enlargement. For these cases of liver, spleen and kidney, if there is a substantial mass, it is also considered to be a manifestation of lymphoma with infiltration. According to these conditions, lymphoma can be staged, and the specific staging will then be treated according to the situation.