Onkológia 6/2012

Establishing diagnosis of hairy cell leukemia (HCL) and identification of the extent of the minimal residual disease (MRD) with flow cytometry of bone marrow aspirate and immunochemistry of trephine biopsy

In the process of establishing diagnosis of hairy cell leukemia (HCL) and identification of the extent of the minimal residual disease (MRD), after treatment in our clinical environment, we use immunophenotypic examination of bone marrow aspirate using flow cytometry (FC) (CD11c, CD25, CD103, HC2), as well as the process of immunochemistry (IHC) staining of trephine biopsy with antibodies against antigens CD20 and DBA44. In retrospect we focused on the comparison of the relevance of the two methodologies in cases when both exams were completed from a single collection of bone marrow. We found 109 paracenteses suitable for result comparison among 32 patients diagnosed with HCL. After the investigation we found statistically important consistent difference which underrates results of FC relative to IHC. The immunophenotypic analysis identified and qualified the pathological clone at level of less than 1 % of the cells, but on the other hand the IHC values reflected more accurately the stage and progress of the disease. In cases of bone marrow infiltration over 1 – 5 % the results of individual specimen collections showed less dispersion of values compared to the FC methodology. Therefore, IHC examination of trephine biopsy specimens should be a part of a diagnostic puncture as well as one of the methods for determination and quantification of MRD.

Keywords: hairy-cell leukemia, flow cytometry, imunochemistry.