Primary pulmonary lymphoma: relationship between clinical features and pathologic findings in 24 cases. The Japan National Chest Hospital Study Group for Lung Cancer.

To elucidate the relationship between the clinical features and pathologic findings of primary pulmonary lymphoma, we reviewed 24 patients with this disease. The pulmonary lymphomas were divided into four groups: (1) B-cell lymphoma composed of small to medium-sized lymphoid cells (19 cases); (2) B-cell lymphoma composed of large lymphoid cells (three cases); (3) T-cell lymphoma (one case); (4) malignant lymphoma of lymphomatoid granulomatosis (LYG) type (one case). Radiographs of the first group revealed a predominance of infiltration associated with ill-defined tumor margins upon gross pathology, corresponding histologically to lymphangitic spread. Air bronchogram and pleural tail or abutment were additional radiographic features. Characteristics of the second group were a nodule or mass evident on radiographs and well-circumscribed tumor margins upon gross pathology. Lack of air bronchogram was an another radiographic feature in this group. Seventeen patients in these two groups underwent complete resection of the tumors and survived without recurrence, whereas four received chemotherapy after biopsy and survived with disease. These results indicate that primary pulmonary B-cell lymphoma is a low-grade malignancy and that complete resection is the only therapy which leads to cure. In a single patient with T-cell lymphoma, the radiographic and pathologic features of the tumor were indistinguishable from those in the first group, but the patient had an unfavorable prognosis. We consider that, from a prognostic viewpoint, it is important to determine the T- or B-immunophenotype of the tumor cells for diagnosis of primary pulmonary lymphoma. The only patient in this series with pulmonary lymphoma of LYG type showed distinctive clinicopathologic findings. We consider that this uncommon disease should be separated from other types of primary pulmonary lymphoma.