Incidence and characteristics of CD4(+)/HLA DRhi dendritic cell malignancies.
OBJECTIVE
Recent reports suggest that CD4(+)/CD56(+)/lineage(-) hematopoietic neoplasias are aggressive types of malignancies involving lymphoplasmacytoid/DC2 dendritic cells (DC). Here, we report on the incidence of DC malignancies and their clinical, biological, phenotypic and cytogenetic characteristics.


METHODS
From a large series of 392 patients with acute myeloblastic leukemia (AML) and 739 with non-Hodgkin's lymphoma (NHL), five cases (three presenting as acute leukemia and two as NHL) showed clinical, morphologic and phenotypic features compatible with a DC malignancy.


RESULTS
The overall incidence of DC malignancies among all AML and NHL cases was 0.76% and 0.27%, respectively. At presentation, these patients displayed cutaneous nodules, splenomegaly and lymph node involvement with variable levels of peripheral blood (PB) and/or bone marrow (BM) infiltration in association with anemia and thrombocytopenia. Cytologic studies showed immature appearing blast cells with negative cytochemistry reactions for both myeloperoxidase and esterases. A highly suggestive DC phenotype based on co-expression of CD123(hi)/HLADR(+)/lin(-)/CD56(+)/CD45(dim) associated with a germline configuration of both the IgH and TCRgamma genes was found in all except one patient who was CD56(-). Expression of other markers compatible with a DC origin was found in all cases.


CONCLUSIONS
We show that DC-derived malignancies can present as either cutaneous lymphoma or acute leukemia, although their incidence is extremely low (<< >1%). While most of these DC neoplasias probably correspond to the malignant counterpart of DC2/lymphoplasmacytoid DC, neoplasias of myeloid DC might also exist, chemotherapy followed by consolidation with ASCT is apparently the most effective strategy for achieving a durable remission in these individuals.
Bueno
Clara
C
Servicios de Citometria y Hematologia, Hospital Universitario de Salamanca, Centro de Investigacio' del Cancer, Universidad de Salamanca, Salamanca, Spain.
Almeida
Julia
J
Lucio
Paulo
P
Marco
Josefa
J
Garcia
Raimundo
R
de Pablos
Jose Maria
JM
Parreira
Antonio
A
Ramos
Fernando
F
Ruiz-Cabello
Francisco
F
Suarez-Vilela
Dimas
D
San Miguel
Jesus F
JF
Orfao
Alberto
A
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D015704:CD4 Antigens / Q000096:biosynthesis* / Q000276:immunology; D003713:Dendritic Cells / Q000737:chemistry* / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006684:HLA-DR Antigens / Q000096:biosynthesis* / Q000276:immunology; D006801:Humans; D016130:Immunophenotyping; D015994:Incidence; D007938:Leukemia / Q000453:epidemiology; D015470:Leukemia, Myeloid, Acute / Q000453:epidemiology* / Q000235:genetics* / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology* / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology / Q000379:methods*; D010641:Phenotype; D016896:Treatment Outcome
D015704:CD4 Antigens; D006684:HLA-DR Antigens