Long bag behind the ear should be alerted to lymphoma, but this symptom is not necessarily caused by lymphoma. The cause of lymphoma is still unclear, or related to infection, immunodeficiency, heredity, etc. This disease is mainly characterized by progressive and painless lymph node enlargement. There are a large number of lymph nodes behind the ear, so once there is a long bag, no obvious pain when touching it, and accompanied by unexplained persistent fever, night sweating, weight loss, etc., you have to be vigilant against lymphoma. However, this kind of bag behind the ear is not necessarily caused by lymphoma, for example, some patients usually do not pay attention to the hygiene behind the ear, which leads to the blockage of sebaceous gland of hair follicles and the formation of sebaceous cysts, and the large cysts are round, with the surface and the skin adhered to each other, which looks like a bag behind the ear. In addition, when germs invade the lymph nodes behind the ear and cause lymph node enlargement and pain, it also looks like a bag. When you find a bag behind the ear, you should go to a specialized hospital in time, follow the advice of a specialist, make a clear diagnosis and standardize the treatment, in order to prevent delay and aggravation of the condition.