Flow cytometric features of angioimmunoblastic T‐cell lymphoma

Abstract

Background: The immunophenotypic features of angioimmunoblastic T-cell lymphoma (AILT) have not been well described.Methods: We retrospectively reviewed our institutional experience with the flow cytometric features of 16 cases of AILT.Results: Multiparameter flow cytometry was able to identify a distinct population of immunophenotypically aberrant T cells in 15 of 16 cases. In 13 lymph node specimens, the neoplastic cells ranged from 1.9 to 87% (median 23%) of cells. The ratio of reactive to neoplastic T cells ranged from 0.01 to 20 (median 1.5); reactive T cells outnumbered neoplastic in 9/13 (69%) cases. The neoplastic populations expressed CD2, CD4, CD5, and CD45RO in all cases, lacked expression of CD8 and CD56 in all cases, and showed negative or dim surface CD3 in most cases. CD10 was expressed by the neoplastic populations in 11 of 14 cases at diagnosis; in 3 of these 11 only a subpopulation of the neoplastic cells was CD10(þ). CD10 tended to be absent on neoplastic cells in staging bone marrows. The neoplastic population in all but one of the 15 positive cases possessed multiple immunophenotypic abnormalities and these were generally retained during the follow-up analyses of several cases.Conclusions: These results indicate the potential utility of flow cytometry in the diagnosis and followup of AILT. q

Immunophenotypic and diagnostic characterization of angioimmunoblastic T-cell lymphoma by advanced flow cytometric technology

“…These authors also showed that this aberrant immunophenotype is exceedingly rare in other leukemic T-cell lymphomas and that detection of cells with this immunophenotype in PB had a 94 % positive predictive value for the diagnosis of AITL. The sCD3-/CD4+ immunophenotype in AITL has been shown previously by other investigators as well [7,20,21]. …”

Angioimmunoblastic T-cell lymphoma in bone marrow: a morphologic and immunophenotypic study

“…Unlike lymph nodes involved by AITL, using IHC, we also did not identify CD21+ or CD35+ FDCs in AITL infiltrates in BM. Our results, in large part, are consistent with what has been observed by other groups [17][18][19]27]. These results suggest that the immunophenotype of AITL is attributable, in large part, to its microenvironment, and therefore, immunophenotypic analysis is relatively less helpful for the workup of AITL in BM compared with lymph nodes.…”

Abnormal immunophenotype of the T‐cell‐receptor beta Chain in follicular‐helper T cells of angioimmunoblastic T‐cell lymphoma

“…Immunophenotypic aberrancies for T-cell-associated antigens (CD2, CD3, CD4, CD5, and CD7) and for CD45 have been reported previously, and our results confirm those findings (8)(9)(10)(11). Testing for CD94, CD161, and killer-cell immunoglobulin-like receptors was not helpful in our cases of AITL, in contrast to the diagnostic utility for clones of large granular lymphocytes in the blood (12).…”