Positive d2-40 lymphatic vessels indicates the possible presence of primary tumor metastasis to lymphatic vessels or lymphatic origin tumor. d2-40 is a specific lymphatic vessel endothelial cell marker commonly used in clinical practice, which can show the infiltration of tumor into lymphatic vessels and assist in determining the stage and prognosis of the tumor; when the primary tumor has metastasis or lymphatic vessel infiltration, cancerous tissues can usually be found in the small blood vessels outside the tumor or in the lymphatic vessels, which will be manifested as d2-40 lymphatic vessel positivity. When the patient has lymphogenic hemangioma, such as splenic lymphangioma and other diseases, due to the congenital local lymphatic vessel development abnormality, the splenic lymphangioma is constantly expanding, showing cystic, spongy, etc.; the results will also be reported as d2-40 lymphangioma positive when the pathology is performed. A single test result of d2-40 lymphangiectasia is not a basis for the diagnosis of the disease, and the patient should consult the medical oncology department in a timely manner, so that the professional doctor can make a comprehensive assessment with the patient’s condition and relevant auxiliary examinations, and carry out standardized treatment after a clear diagnosis.