inapparently normal bonemarrow trephine specimens frompatients withnodalfollicular lymphoma

Aim-To establish theroleofimmunohistochemistry (using a limited panelof antibodies) in detecting minimalinvolvementby follicular lymphoma in routinely processed bonemarrow trephine specimens, whichshowno obvious morphological (light microscopic) evidence of lymphoma;to determine whetherbcl-2 immunostaining in bone marrow distinguishes betweenbenignandmalignant infiltrates inapatient withnodalfollicular lymphoma. Methods-Twenty seven consecutively selected paraffin wax embedded,formalin fixedbone marrow trephine specimens were stained withthefollowing antibodies: anti-bcl-2, anti-CD79a, anti-CD3, and ic andklight chains, usingtheStreptavidin biotin complextechnique. Results-Five of the 27 cases, which showedno evidence ofinvolvement byfollicularlymphoma on routinestains, showedmonotypicB cells on immunohistochemistry. Two ofthecases were diffuse, whiletheremaining threeshowed mini-aggregates aroundbonytrabeculae. Inallfivecases thelymphomatousinfiltrates were strongly bcl-2positive. Reactive B lymphoidnodulesdidnotshow thesame degreeofbcl-2positivity, and negative cells couldbe discerned within thereactive nodules. Conclusions-There ismeritinstudying