title: Assessment of cell proliferation by Ki-67 staining and flow cytometry in fine needle aspirates (FNAs) of reactive lymphadenitis and non-Hodgkin's lymphomas.
abstract: This study was undertaken to assess cell proliferation in FNAs from a series of 57 non-Hodgkin's lymphomas (NHL) and 11 cases of reactive lymphadenitis using Ki-67 staining and flow cytometry (FCM). The results were compared and correlated to the cytomorphological subgrouping according to Kiel classification. The mean percentages of Ki-67 positivity were 16.6% and 61.1% for low and high grade lymphomas, respectively (P < 0.001). The mean S-phase fraction (SPF) determined by FCM was 4.61% for low grade and 12.9% for high grade lymphomas (P < 0.001). The figures for Ki-67 positivity and S-phase fraction in reactive lymphadenitis were 16.8% and 40%, respectively. We observed a strong correlation in low grade lymphomas between Ki-67 and SPF. A good correlation was also found in reactive lymphadenitis. In high grade lymphomas, however, with highly scattered Ki-67 and S-phase values, this correlation was lost. In some cases this discrepancy can be explained by a rich admixture of non-neoplastic, non-proliferating cells in aspirates from diploid tumours. In addition, the existence of a minor aneuploid tumour cell population of high proliferation such as that in Ki-1 lymphomas will not be accurately analysed by FCM but is easily assessed by Ki-67 staining. However, the main reason seems to be a high variability between the fraction of cells in S-phase and the total number of cells in G1, S and G2 in individual tumours.
authors.affiliation: Unit of Molecular Pathology, Institute of Pathology and Molecular Immunology of the University of Porto, Portugal.
authors.forename: F
authors.initials: F
authors.lastname: Schmitt
authors.forename: E
authors.initials: E
authors.lastname: Tani
authors.forename: B
authors.initials: B
authors.lastname: Tribukait
authors.forename: L
authors.initials: L
authors.lastname: Skoog
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D004396:Coloring Agents; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008199:Lymphadenitis / Q000276:immunology / Q000473:pathology*; D008228:Lymphoma, Non-Hodgkin / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D016196:S Phase / Q000276:immunology
chemical_list: D004396:Coloring Agents; D019394:Ki-67 Antigen