Use of image analysis and immunostaining of bone marrow trephine biopsy specimens to quantify residual disease in patients with B-cell chronic lymphocytic leukemia

Marrow residual disease (RD) in patients with B-cell chronic lymphocytic le ukemia (B-CLL) who are in complete remission (CR) after treatment with puri ne analogues is reported to have a prognostic value, but sample dilution, f actors interfering with marrow aspiration, or undetectable immunoglobulin r earrangement can affect the assessment of RD by molecular or immunologic me thods. As demonstrated for hairy cell leukemia and follicular lymphoma, bon e marrow trephine biopsy specimen immunostaining (BMT/IS) can successfully detect residual malignant cells. The aim of this study was to use BMT/IS an d computerized image analysis (CIMA) of bcl-2-positive cells to quantify RD in B-CLL patients in CR, after achievement of CR and more than 1 year late r. This methodology was compared with other conventional techniques, i.e., cytologic, flow cytometric, cytogenetic, and molecular analysis. BMT/IS rea dily detected RD in every trephine biopsy specimen examined, either after C R or at distant follow-up. CIMA allowed an objective quantification of resi dual B-CLL cells, as evidenced by the correlation with semiquantitative pol ymerase chain reaction results. Both analyses indicated a progression of RD , This finding was also supported (but inconsistently) by the other techniq ues. CIMA with an interstitial labeling index, therefore, seems to be a rep roducible and sensitive method to detect persistence and progression of RD in patients with B-CLL. This method could apply to other hematologic malign ancies infiltrating the bone marrow.