Hodgkin-like anaplastic large cell lymphoma (previously designated in the REAL classification) has same immunophenotypic features to classical Hodgkin lymphoma.
In the WHO classification, the majority of Hodgkin-like ALCL cases as defined by the REAL classification are considered to be CHL. However, establishing a histological diagnosis for the gray zone between CHL and ALCL is often confusing. In this study, we re-evaluated such cases by performing immunohistochemistry with antibodies against PAX-5/BSAP, Oct.2, and BOB.1/OBF.1. Expression of PAX-5/BSAP was observed in 88% (76/87) of CHL specimens and none (0/11) of ALK-positive ALCL specimens. Among specimens of Hodgkin-like ALCL and ALK-negative ALCL, expression of PAX-5/BSAP was observed in 77% (20/26) and 18% (3/17), respectively. Most of the PAX-5/BSAP-positive specimens were negative for Oct.2 and/or BOB.1/OBF.1 except for four CHL specimens. Our results may support the WHO classification in which most cases of Hodgkin-like ALCL are classified as CHL. However, the patients with Hodgkin-like ALCL with CHL-immunophenotype (PAX-5/BSAP-positive and negative for Oct.2 and/or BOB.1) did not have a favorable outcome, with a 5-year OS rate of 58%.
Tamaru
Jun-Ichi
J
Department of Pathology, Saitama Medical Center, Saitama Medical University, Kawagoe, Japan. jtamaru@saitama-med.ac.jp
Tokuhira
Michihide
M
Nittsu
Nozomi
N
Nakamura
Shigeo
S
Ichinohasama
Ryo
R
Suzuki
Ritsuro
R
Mori
Hiraki
H
Takagi
Toshiyuki
T
Suzuki
Takahiro
T
Itami
Jun
J
Itoyama
Shinji
S
Mikata
Atsuo
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000077548:Anaplastic Lymphoma Kinase; D014408:Biomarkers, Tumor / Q000235:genetics; D003937:Diagnosis, Differential; D005260:Female; D015973:Gene Expression Regulation, Leukemic; D006689:Hodgkin Disease / Q000175:diagnosis* / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D006801:Humans; D016130:Immunophenotyping; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis* / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D050813:Octamer Transcription Factor-2 / Q000235:genetics; D051757:PAX5 Transcription Factor / Q000235:genetics; D011505:Protein-Tyrosine Kinases / Q000235:genetics; D020794:Receptor Protein-Tyrosine Kinases; D012189:Retrospective Studies; D016019:Survival Analysis; D015534:Trans-Activators / Q000235:genetics
D014408:Biomarkers, Tumor; D050813:Octamer Transcription Factor-2; D051757:PAX5 Transcription Factor; C497281:PAX5 protein, human; C091546:POU2AF1 protein, human; D015534:Trans-Activators; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases