[A case of malignant lymphoma associated with diffuse pulmonary involvement successfully treated with rituximab]

A 66-year-old man was admitted to our hospital with a chief complaint of fever. Histopathological examination of the inguinal lymph nodes revealed follicular B-cell non-Hodgkin's lymphoma (NHL). In spite of 9 cycles of chemotherapy (CHOP/COP), progression of the disease was seen. Fever and dyspnea developed. The chest radiograph revealed diffuse pulmonary infiltrates. Transbronchial biopsy revealed pulmonary involvement of diffuse B-cell lymphoma. The tumor cells showed positive staining for CD20. Salvage chemotherapy (ESHAP, EPOCH) was not effective. We decided to perform mono-immunotherapy with the monoclonal CD20 antibody rituximab. One month later, the patient was in almost complete remission without adverse events. It is suggested that rituximab may be effective for refractory NHL with pulmonary involvement.