title: Flow cytometric evaluation of CD38 expression assists in distinguishing follicular hyperplasia from follicular lymphoma.
abstract: The distinction of follicular lymphoma (FL) from reactive follicular hyperplasia (FH) can be a diagnostic challenge in flow cytometry. In this study, the median fluorescent intensity (MFI) of CD38 as assessed by flow cytometry on B and T cell subpopulations in 102 lymph nodes specimens with histopathologically confirmed FL was compared with 55 cases of FH. The MFI of CD38 was highly significantly reduced in the neoplastic B cells in FL when compared with the reactive germinal center B cells in FH (P < 1.0E-16). The MFI of CD38 did not differ between the non-neoplastic B-cells in FL and nongerminal center B-cells in FH (P = 0.14) or between T-cells and non-neoplastic B-cells in FL (P = 0.63). A marginal increase in the MFI of CD38 was seen for T cells in FL compared with FH (P = 0.04). An increased difference in the MFI of CD38 was identified for T-cells compared with nongerminal center B-cells in FH (P = 0.005). No difference in CD38 expression was seen between Grades 1, 2, or 3 FL. The study also confirmed increased expression of CD10 (P < 1.0E-9), decreased CD19 (P < 1.0E-22), and CD20 (P < 1.0E-16) in FL in comparison with FH, as has been previously reported. This study identified decreased CD38 as a common finding in FL in comparison with FH and provides an additional tool to help differentiate FL from FH by flow cytometry.
authors.affiliation: Department of Laboratory Medicine, University of Washington Medical Center, Seattle, Washington 98195, USA.
authors.forename: Kristin
authors.initials: K
authors.lastname: Mantei
authors.forename: Brent L
authors.initials: BL
authors.lastname: Wood
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000378:metabolism*; D001402:B-Lymphocytes / Q000378:metabolism / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism; D003937:Diagnosis, Differential; D005434:Flow Cytometry / Q000379:methods*; D005453:Fluorescence; D006801:Humans; D016130:Immunophenotyping; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology*; D008224:Lymphoma, Follicular / Q000175:diagnosis* / Q000378:metabolism; D019310:Pseudolymphoma / Q000175:diagnosis* / Q000378:metabolism; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D051997:ADP-ribosyl Cyclase 1