Lymphoproliferative disorders in the bone marrow: histologic criteria for classification and staging.

Malignant lymphoproliferative disorders (LPD) were investigated in bone marrow biopsies of 1565 untreated patients. Marrow involvement was found in 90 per cent of multiple myeloma (MM), 70 per cent of non-Hodgkin lymphomas (NHL) and 10 per cent of Hodgkin disease (HD). In MM and NHL there were five major entities according to the predominant proliferative cell type: 1. plasmacytic, 2. lymphocytic, 3. hairy cell, 4. immunocytic and 5. centrocytic. On the basis of bone marrow histology they were classified into 3 distinct sub-types each of which had an independent prognostic significance. The mode of spread of all the LPD fell into one of six architectural patterns which together with the tumour cell burden (the quantity of infiltration in the biopsy) also had a significant predictive value. Consequently, bone marrow biopsy is a valuable diagnostic tool for histologic classification and clinical staging of any patient with LPD.