[T-cell/histiocyte-rich B-cell lymphoma: histology, immunophenotype and differential diagnosis].
OBJECTIVE
To study the histology, immunophenotype and differential diagnosis of T-cell/histiocyte-rich B-cell lymphoma (TCRBCL).


METHODS
A review of 245 cases of so-called Hodgkin lymphoma diagnosed during the period from 1980 to 2000 in 3 hospitals in Guangzhou, 8 cases were reclassified as TCRBCL, according to the 2001 World Health Organization classification of lymphoid neoplasms. An additional 8 cases of TCRBCL were retrieved from consultation files, as well as routine biopsy cases encountered between 2000 and 2004. Immunohistochemical studies were performed on paraffin-embedded tissue by SP technique in order to study the immunophenotype of the large neoplastic cells (CD20, CD79a, CD3, CD45RO, CD15, CD30, CD10, bcl-6 and EMA) and background non-neoplastic cells (CD3, CD8, CD20, CD45RO, CD79a, CD57, CD68, CD21, CD35, cyclin D1, TIA-1). In-situ hybridization for EBER 1/2 and immunoglobulin heavy chain gene rearrangement study were also performed in 4 and 4 cases respectively.


RESULTS
Among the TCRBCL cases studied, there were 8 males and 8 females. The age of patients ranged from 10 to 68 years old (mean = 40.3 years old). All had lymphadenopathy and hepatosplenomegaly. On presentation, 3 cases belonged to stage II, 10 cases stage III and 3 cases stage IV. Histologically, scattered atypical large neoplastic cells were seen in a background of small lymphocytes and sometimes histiocytes. The large cells exhibited CD20+, CD79a+, EMA+, CD15- and CD30- phenotype. On the other hand, the background small lymphocytes were CD3 and CD45RO-positive. Most of these background T cells expressed CD8 and TIA-1, while they were mostly CD57-negative. The histiocytic cells were CD68-positive; and CD21 and CD35-positive follicular dendritic cell meshworks were absent. In-situ hybridization for EBER 1/2 showed negative nuclear signals. Immunoglobulin heavy chain gene rearrangement study revealed clonal pattern in all the 4 cases tested.


CONCLUSIONS
TCRBCL is a rare subtype of lymphoma, with distinctive histology and immunophenotype. The above features are helpful in delineating this entity from Hodgkin lymphoma, reactive lymphoid hyperplasia and lymphomatoid granulomatosis.
Department of Pathology and Laboratory, Guangdong Provincial People's Hospital, Guangzhou 510080, China. yanh_liu@yahoo.com
Yan-hui
YH
Liu
Heng-guo
HG
Zhuang
Han-liang
HL
Lin
Qiu-liang
QL
Wu
Dong-lan
DL
Luo
Xin-lan
XL
Luo
D000293:Adolescent; D000328:Adult; D000368:Aged; D018951:Antigens, CD20 / Q000378:metabolism; D051925:CD79 Antigens / Q000378:metabolism; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006689:Hodgkin Disease / Q000473:pathology; D006801:Humans; D016130:Immunophenotyping; D016393:Lymphoma, B-Cell / Q000276:immunology / Q000473:pathology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000378:metabolism; D009367:Neoplasm Staging; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology*
D018951:Antigens, CD20; D051925:CD79 Antigens; D018396:Mucin-1