Aims: Lennert's lymphoma is a rare variant of peripheral T-cell lymphoma (PTCL) not otherwise specified (NOS). The aim of this study was to further characterize this tumour. Methods and results: Historical material of 97 lymphomas with a high content of epithelioid cells, collected at the Kiel Lymph Node Registry were reviewed, by applying immunohistochemistry and current diagnostic criteria. Among all cases revised, various B-cell lymphoma entities (25 cases), Hodgkin lymphomas (21 cases) and PTCL subtypes (48 cases) could be identified. A distinctive subgroup of eight PTCLs was found that were regarded as genuine Lennert's lymphomas. These cases were characterized by mild atypia, a non-activated cytotoxic phenotype [TIA1 cytotoxic granule-associated RNA binding protein (TIA1)-positive + and granzyme B-negative], and a substantial lack of follicular T-helper (T FH) cell markers. Among the other PTCLs, including angioimmunoblastic T-cell lymphoma and PTCL NOS, many cases with positivity for more than three T FH cell-associated molecules were recorded. Conclusions: Our study shows that, according to current criteria, Lennert's lymphoma is a rare but distinctive entity among epithelioid cell-rich lymphomas, differing on grounds of morphology and immunophenotype from other PTCL subtypes. An additional finding is the broad morphological spectrum of epithelioid-cell rich PTCLs showing a T FH cell phenotype
Revising the historical collection of epithelioid cell-rich lymphomas of the Kiel Lymph Node Registry: what is Lennert's lymphoma nowadays? / Hartmann S.; Agostinelli C.; Klapper W.; Korkolopoulou P.; Koch K.; Marafioti T.; Piccaluga PP.; Patsouris E.; Pileri S.; Hansmann ML.. - In: HISTOPATHOLOGY. - ISSN 0309-0167. - STAMPA. - 59:6(2011), pp. 1173-1182. [10.1111/j.1365-2559.2011.04069.x]
Revising the historical collection of epithelioid cell-rich lymphomas of the Kiel Lymph Node Registry: what is Lennert's lymphoma nowadays?
AGOSTINELLI, CLAUDIO;PICCALUGA, PIER PAOLO;PILERI, STEFANO;
2011
Abstract
Aims: Lennert's lymphoma is a rare variant of peripheral T-cell lymphoma (PTCL) not otherwise specified (NOS). The aim of this study was to further characterize this tumour. Methods and results: Historical material of 97 lymphomas with a high content of epithelioid cells, collected at the Kiel Lymph Node Registry were reviewed, by applying immunohistochemistry and current diagnostic criteria. Among all cases revised, various B-cell lymphoma entities (25 cases), Hodgkin lymphomas (21 cases) and PTCL subtypes (48 cases) could be identified. A distinctive subgroup of eight PTCLs was found that were regarded as genuine Lennert's lymphomas. These cases were characterized by mild atypia, a non-activated cytotoxic phenotype [TIA1 cytotoxic granule-associated RNA binding protein (TIA1)-positive + and granzyme B-negative], and a substantial lack of follicular T-helper (T FH) cell markers. Among the other PTCLs, including angioimmunoblastic T-cell lymphoma and PTCL NOS, many cases with positivity for more than three T FH cell-associated molecules were recorded. Conclusions: Our study shows that, according to current criteria, Lennert's lymphoma is a rare but distinctive entity among epithelioid cell-rich lymphomas, differing on grounds of morphology and immunophenotype from other PTCL subtypes. An additional finding is the broad morphological spectrum of epithelioid-cell rich PTCLs showing a T FH cell phenotypeI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.