Bone marrow flow cytometry in staging of patients with B-cell non-Hodgkin lymphoma.
BACKGROUND
Bone marrow biopsies are routinely performed for staging patients with B-cell non-Hodgkin lymphoma (NHL). In addition to histomorphological studies, ancillary tools may be needed for accurate diagnosis. We investigated the clinical utility of multiparameter flow cytometric examination of bone marrow aspirates.


METHODS
A total of 248 bone marrow specimens from 232 patients diagnosed with B-cell NHL were examined. Monoclonal antibodies directed against CD19, CD20, CD10 (or CD5), and κ and λ immunoglobulins were used. Multi-stage sequential gating was performed to select specific cells of interest, and the results were compared with bone marrow histology.


RESULTS
The concordance rate between histomorphology and flow cytometry was 91.5% (n=227). Eight cases (3.2%) were detected by flow cytometry alone and were missed by histomorphology analysis, and 6 of these 8 cases showed minimal bone marrow involvement (0.09-2.2%). The diagnosis in these cases included large cell lymphoma (n=3), mantle cell lymphoma (n=3), and mucosa-associated lymphoid tissue (MALT) lymphoma (n=2). Thirteen cases were histopathologically positive and immunophenotypically negative, and the diagnoses in these cases included diffuse large cell lymphoma (n=7), T-cell/histiocyte-rich large B-cell lymphoma (n=2), anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (n=1), follicular lymphoma (n=1), MALT lymphoma (n=1), and unclassifiable lymphoma (n=1).


CONCLUSIONS
Multi-color flow cytometry can be a useful method for assessing bone marrow in staging NHL and also plays a complementary role, especially in detecting small numbers of lymphoma cells.
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Borahm
B
Kim
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Seung-Tae
ST
Lee
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Hee-Jin
HJ
Kim
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Sun Hee
SH
Kim
D000911:Antibodies, Monoclonal / Q000276:immunology; D018941:Antigens, CD19 / Q000276:immunology / Q000378:metabolism; D018951:Antigens, CD20 / Q000276:immunology / Q000378:metabolism; D001853:Bone Marrow / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D016393:Lymphoma, B-Cell / Q000473:pathology*; D008297:Male; D009367:Neoplasm Staging; D015260:Neprilysin / Q000276:immunology / Q000378:metabolism
D000911:Antibodies, Monoclonal; D018941:Antigens, CD19; D018951:Antigens, CD20; D015260:Neprilysin
Bone marrow; Flow cytometry; Immunophenotyping; Non-Hodgkin lymphoma