There are malignant and benign lung lymphomas. Benign ones are called pulmonary pseudolymphoma, malignant ones are called low-grade malignant lymphoma, and most of the lung lymphomas are benign. The best treatment is surgical resection to completely remove the lesion, and chemotherapy and radiotherapy are usually not needed. However, regular postoperative review is still needed to be alert to the recurrence of lymphoma. Some data show that about half of benign lung lymphomas develop into malignant lymphomas, and both chemotherapy and radiotherapy can cause lung pseudolymphoma to develop into malignant lymphoma. There is also a category called highly malignant B-cell lymphoma that is relatively rare and has a poor treatment and prognosis.