Primary lymphosarcoma of the lung. Report of a case and summary of the literature.

That lymphogenous diseases may involve the lung parenchyma is well known. This involvement is usually found in cases with wide dissemination. The incidence varies widely 1 up to 33%. Occasionally, isolated organ lymphomas may be seen. An incidence up to 10% in bowel and stomach has been reported. 2 The lung, however, in spite of its abundant lymph supply, 3 rarely is the primary site. In two large series of malignant lymphomas, totaling 814 cases, only one case was considered as having arisen from the pulmonary parenchyma. 2,4 In fact, there has been much doubt in the past as to whether the lymphosarcoma arose from the lung parenchyma or began from the hilar nodes and then involved the lung. However, the reported cases during the last two decades have proved that, even though it is rare, primary lymphosarcoma may arise from the lung parenchyma itself. The following case is regarded