Failed or inadequate bone marrow aspiration:: a fast, simple and cost-effective method to produce a cell suspension from a core biopsy specimen

Failure to aspirate bone marrow (BM) diminishes diagnostic accuracy and efficiency because BM cell suspensions are crucial for modern haematological diagnostic methods such as cytomorphology, flow cytometric immunophenotyping (FCI), cytogenetics or fluorescent in situ hybridization (FISH). We mechanically disaggregated unfixed BM core biopsies with the Dako Medimachine in 65 cases of macroscopically suspected dry taps. Cytospins, three-colour FCI and in some cases karyotyping and FISH were performed successfully. Most cytospins (34 of 50; 68.0%) were of good quality, while a further 18.0% showed moderate but still informative quality. FCI showed good quality in 36 of 60 (60.0%) cases; in 13.3% quality was moderate, but diagnostically useful results were obtained. Surprisingly, all four cases of formerly undiagnosed BM-carcinosis could be clearly detected on cytospins. Finally, five of seven (71.4%) attempts yielded analysable metaphases mostly in cases where no metaphases could be obtained from BM or peripheral blood. The described method of mechanical disaggregation of unfixed BM core biopsies compares favourably with other published approaches, allowing the application of all techniques where BM cell suspensions are needed. Thus, it can help to establish the underlying diagnosis in patients with abnormalities in peripheral blood and unsuccessful marrow aspirations.