Most lung nodules do not cause swelling of the upper limbs. Lung nodules caused by malignant tumors may cause swelling of the upper limbs when the superior vena cava is compressed and superior vena cava obstruction syndrome occurs. Lung nodules are nodules with a diameter of less than 3cm, which can be categorized into benign and malignant nodules. When pulmonary nodules are small, they generally have little effect on the lungs and have no or mild clinical symptoms. When the lung nodules are large or widely distributed, symptoms such as cough, chest tightness and shortness of breath may occur, and generally do not cause swelling of the upper extremities. When lung nodules are caused by malignant tumors in the lungs, the malignant tumors compress the superior vena cava, causing superior vena cava obstruction syndrome, which is manifested by venous varicose veins in the face, neck, upper limbs and upper chest, and subcutaneous tissue edema, at which time the manifestation of swelling of the upper extremities may occur. Lung nodules with upper extremity edema may also be caused by cardiogenic edema, hepatic edema, nephrogenic edema, malnutrition edema and other causes. It is recommended that the patient should consult the doctor in time, complete the examination, clarify the cause of the disease, and treat the cause of the disease under the guidance of the specialist.