[Bone marrow biopsy in non-Hodgkin's lymphoma: experience with 259 samples]

A study performed on 259 cases of bone-marrow biopsy specimens from 121 patients with non-Hodgkin's lymphoma (NHL) is presented after an introduction dealing with several well-known facts. Specific involvement of the initial samples was present in 53.45% of the cases. Such involvement was more frequent in stages III and IV, although no difference was found between the clinical forms, A or B. Stage progression due to positive bone-marrow biopsy occurred in 26% of the patients, and in 25% of these it was from stages 0 to II onto stage IV. Low-grade lymphomas showed higher bone-marrow involvement than high-grade ones (p = 0.025); specific involvement significantly influenced survival in only high-grade lymphomas, not in the low-grade ones, when the series was considered as a whole. Absolute compatibility between lymph-node and bone-marrow cellularity was found in 71% of the cases, and in 85% was taken into account. Six possible histological lesions are described herein, while for practical purposes, the use of 5 patterns of involvement is recommended, namely, interstitial, nodular, patchy, mixed nodular-patchy, and diffuse. Patchy pattern associated to low-grade and skin-involvement lymphomas. Although those patterns had non-significant influence on survival, this last was found when comparing diffuse pattern with the remainders; similarly, the diffuse pattern correlated with significantly lower haemoglobin rates. Finally, fibrosis was present in 58% of the positive biopsies and in 94% of the lesions, it being thus considered as a marker of bone-marrow involvement.