Morphological studies of 84 untreated patients subjected to laparotomy for the staging of non-Hodgkin's lymphomas.

Abstract

The pathologic findings in 84 untreated patients subjected to laparotomy and open iliac crest bone marrow biopsy for the staging of malignant lymphomas other than Hodgkin's disease at Stanford University Medical Center are presented. Fifty-one (61%) of these 84 patients had lymphomatous involvement of one or more sites below the diaphragm. The applicability of the histopathologic classification of Rappaport, Winter, and Hicks was confirmed by virtue of the constancy of the histologic features in multiple lesions in 43 patients (84%) (including 1 patient with a composite lymphoma). Six patients, however, showed two different histologic patterns in two or more sites, and in two additional patients with a composite lymphoma, the initial composite pattern was not reproduced in other sites. Three patients had the remarkable association of a non-Hodgkin's lymphoma with Hodgkin's disease either within the same lymph node (composite lymphoma) or in a separate site. In the remaining 75 patients (excluding the 9 patients with multiple histologies), 43 had nodular lymphomas and 32 diffuse lymphomas. The nodular lymphomas showed a tendency for widespread dissemination by virtue of their involvement of the abdomen in 31 patients (72%) and bone marrow in 12 patients (28%). In contrast, diffuse lymphomas involved the abdomen in only 11 patients (28%). Diffuse histiocytic lymphomas showed a low incidence of early dissemination, involving the spleen and abdominal lymph nodes in only 5 (28%) and the bone marrow in 2 (11%) of 18 patients. This clearly indicates that evaluation of stage of the disease alone does not suffice in assessing response to therapy and long-term survival, in view of the poor prognosis of diffuse histiocytic lymphomas despite their initial localized involvement. It also emphasizes the importance of differentiating lymphomas according to cytologic type and architectural pattern. Occult abdominal disease was located in mesenteric lymph nodes (56%), splenic hilar lymph nodes (54%), para-aortic lymph nodes (40%), and spleen (34%). Thirteen of 25 spleens involved by lymphoma weighed less than 200 grams. Granulomas similar to those previously described by us in patients with Hodgkin's disease were observed in 5 patients.