Bone marrow biopsy in chronic lymphocytic leukemia: a review of its prognostic importance.

In recent years important advances have been made in predicting the survival of patients with chronic lymphocytic leukemia (CLL). Other prognostic factors in addition to clinical staging systems have proved to be of value. Among them, bone marrow biopsy has emerged as a particularly useful prognostic tool. Patients with nondiffuse bone marrow involvement survive longer than those with diffuse involvement. This parameter is useful for subclassifying clinical stages in low- (nondiffuse patterns) and high- (diffuse patterns) risk groups. The use of a combined clinicopathological staging system for CLL seems advisable.