Large B-cell lymphoma with Hodgkin's features.
OBJECTIVE
To describe the features of a series of nine cases of diffuse large B-cell lymphoma (DLBCL) showing morphological and immunophenotypic features that are intermediate with Hodgkin's lymphoma (HL).


RESULTS
Most cases (6/9) presented as mediastinal tumours affecting young males, while the other three cases arose in extramediastinal locations. Histopathologically, tumours showed diffuse large cell areas in a polymorphous background, with pleomorphic cytology and the common presence of Hodgkin's and Reed-Sternberg cells. Immunophenotypically, tumours shared features of DLBCL and classical HL, with expression of CD30, CD15 (6/9), and a full B-cell profile including CD45RB, CD20, CD79a and OCT2. Epstein-Barr virus-latent membrane protein expression was found in 2/9 cases. The majority of tumours had immunohistochemical features consistent with activation of the NF-(kappa)B pathway, including nuclear location of the c-REL/p65 subunit, overexpression of phosphorylated I(kappa)B(alpha), and overexpression of NF-(kappa)B targets. Finally, 2/9 cases showed 3q27 (BCL6) rearrangement, and 1/9 had p53 gene mutations, both of which are rarely detected in classical HL.


CONCLUSIONS
These findings suggest that DLBCLs with HL features constitute a distinctive subgroup of aggressive lymphomas whose neoplastic growth and peculiar characteristics could be facilitated by a particular microenvironment found in the mediastinum.
Lymphoma Group, Molecular Pathology Programme, Centro Nacional de Investigaciones Oncologica (CNIO), Madrid, Spain. jfgarcia@cnio.es
J F
JF
García
M
M
Mollejo
M
M
Fraga
J
J
Forteza
J A
JA
Muniesa
M
M
Pérez-Guillermo
C
C
Pérez-Seoane
T
T
Rivera
P
P
Ortega
M A
MA
Piris
D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D004268:DNA-Binding Proteins / Q000032:analysis / Q000235:genetics; D003937:Diagnosis, Differential; D005260:Female; D015321:Gene Rearrangement; D006689:Hodgkin Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D019394:Ki-67 Antigen / Q000032:analysis; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D011518:Proto-Oncogene Proteins / Q000032:analysis / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D051560:Proto-Oncogene Proteins c-bcl-6; D014157:Transcription Factors / Q000032:analysis / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics
D015703:Antigens, CD; D004268:DNA-Binding Proteins; D019394:Ki-67 Antigen; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051560:Proto-Oncogene Proteins c-bcl-6; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53