Prognostic Significance of Bone-Marrow Patterns in Chronic Lymphocytic Leukaemia

Abstract

Bone marrow biopsy was performed in 63 [human] cases of chronic lymphocytic leukemia (CLL). The following 4 different histological patterns were observed: interstitial (lymphoid infiltration without displacement of fat cells) in 12 cases; nodular (abnormal lymphoid nodules without interstitial infiltration) in 10 cases; mixed (combination of the first 2 patterns) in 21 cases; and diffuse (replacement of hemopoietic and fat cells by lymphoid infiltration) in 20 cases. Statistical analysis of actuarial curves showed a significant difference of survival probability according to the bone marrow infiltration patterns. In patients with interstitial or nodular patterns the life expectancy is significantly longer than in those with mixed or diffuse patterns. A significant degree of correlation between bone marrow infiltration patterns and different methods of clinical staging in CLL was apparent. The different bone marrow infiltration patterns in CLL probably reflects variations in the amount of lymphoid accumulation during the natural course of this disease. Because of its prognostic significance, bone marrow biopsy should have a place in CLL evaluation and staging.