A patient's face with one side drifting into purple blood cells representing a hematologic neoplasmA patient's face with one side drifting into purple blood cells representing a hematologic neoplasm
Why is it important to talk
about BPDCN and CD123?
Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN)
Quick look at BPDCN
  • BPDCN is a rare and clinically aggressive hematologic malignancy with poor outcomes1-3
  • BPDCN is characterized by variable dermatologic and hematologic manifestations and can easily be mistaken for more common hematologic malignancies4-8
  • Cooperation with dermatologists and hemato-oncologists is key for a correct diagnosis of BPDCN2,9
  • Biopsies of skin, bone marrow or secondary sites are critical for accurate diagnosis of BPDCN6,9,10
  • The marker triad – CD123, CD4 and CD56 – helps confirm the diagnosis of BPDCN*1,4,6,7,11,12
* The diagnosis of BPDCN requires immunophenotyping and fundamentally relies on the demonstration of CD4, CD56, CD123, CD303, and TCL1 expression, together with a lack of expression of markers for B cells, T cells, myeloid or monocytic cells, and NK cells.4,10
Early diagnosis is critical for BPDCN patients and multidisciplinary cooperation is required3,13
Consider adding the CD123 marker to your hematologic diagnostic panels4,10,11
What is BPDCN?
BPDCN is a rare and clinically aggressive hematologic malignancy with poor outcomes1-3
2001
Blastic NK-cell
lymphoma
(WHO classification)
Nomenclature based
on blastic appearance
and CD56 expression15
2008
BPDCN
(WHO classification)
Classified as a subset of
AML and related
precursor neoplasms9
2016
BPDCN
(WHO classification)
Classified as a unique
neoplasm under myeloid
neoplasms and acute
leukemia17
1995
Agranular CD4+
NK-cell leukemia
First description of
unique agranular
morphology14
2005
CD4+ / CD56+ hematodermic
neoplasm
(WHO-EORTC classification)
Nomenclature based on
immunophenotype and skin
involvement15,16
1995
Agranular CD4+
NK-cell leukemia
First description of unique
agranular morphology14
2001
Blastic NK-cell lymphoma
(WHO classification)
Nomenclature based on blastic
appearance and CD56 expression15
2005
CD4+ / CD56+ hematodermic
neoplasm (WHO-EORTC
classification)
Nomenclature based on
immunophenotype and skin
involvement15,16
2008
BPDCN (WHO classification)
Classified as a subset of AML and
related precursor neoplasms9
2016
BPDCN (WHO classification)
Classified as a unique neoplasm
under myeloid neoplasms and
acute leukemia17
BPDCN typically presents in older men
 
~75%
of patients with BPDCN are men1,6
Most often diagnosed at
60 to 70 years
of age, BPDCN can develop at any age1,4,6
Affects all races and geographic locations4
Despite an initial response to chemotherapy in the first-line setting, BPDCN remains an aggressive leukemia and patients are faced with a dismal prognosis and poor outcomes1,2
  • Historically, median overall survival is approximately 8 to 14 months after diagnosis1,18
  • Mean time between onset of lesions and diagnosis of BPDCN was 6.2 months5
Historical overall survival rate for patients diagnosed with BPDCN
BPDCN requires early diagnosis to help improve patients’ poor outcomes and provide them with appropriate treatment.3,4
BPDCN presents with variable dermatologic and hematologic manifestations4-8
~85% to 90%
of patients present with skin lesions of variable dermatologic presentation5-7,19
  • Skin lesions vary in size, shape, and color, and are often nonpruritic6
  • Tumor cells predominantly infiltrate the dermis, sparing the epidermis6,10,19
~60% to 90%
of patients present with leukemic disease20
 
  • Primary sites of involvement include bone marrow and peripheral blood6,21
  • Secondary sites of involvement include lymph nodes and viscera4,6
Close cooperation with dermatologists and pathologists is key for a correct diagnosis of BPDCN.3
BPDCN’s similarity to other hematologic malignancies may contribute to misdiagnosis5
BPDCN may be confused with3,4,8,21-23
Acute myeloid leukemia (AML) Diffuse large B-cell lymphoma (DLBCL)
Chronic lymphocytic leukemia (CLL) Peripheral T-cell lymphoma (PTCL)
Adult T-cell leukemia/lymphoma (ATL/ATLL) Leukemia cutis
Chronic myelomonocytic leukemia (CMML) Cutaneous T-cell lymphoma (CTCL)
Diffuse large B-cell lymphoma (DLBCL)
Peripheral T-cell lymphoma (PTCL)
Leukemia cutis
Cutaneous T-cell lymphoma (CTCL)
How to diagnose BPDCN?
Biopsies of skin, bone marrow or secondary sites are critical for accurate diagnosis of BPDCN6,9,10
An early skin biopsy can help patients obtain an accurate and timely diagnosis of their hematologic malignancies.4,13
Punch biopsy of a skin lesion
Punch biopsy of a skin lesion showing BPDCN
Punch biopsy of a skin lesion showing BPDCN (H & E stain, ×40). Inset shows medium-sized malignant cells sparing the epidermis (H & E stain, ×1000).9
Reprinted by permission of SAGE Publications, Inc.
Bone marrow core biopsy
Bone marrow core biopsy showing diffuse infiltration by BPDCN
Bone marrow core biopsy showing diffuse infiltration by BPDCN (H & E stain, ×600).9
Reprinted by permission of SAGE Publications, Inc.
Multidisciplinary cooperation reducing the lapse between lesion presentation and diagnosis may improve patient outcomes.3,13
The marker triad – CD123, CD4 and CD56 – helps confirm the diagnosis of BPDCN*1,4,6,7,11,12
  • In BPDCN, CD123 is a useful diagnostic marker and therapeutic target4,18
    – CD123 is highly expressed on BPDCN cells (~ 95 %) and negligibly expressed on healthy cells1,7,11,12,18
    – CD123 can be identified through any biopsy of malignant cells24
A graphic showing that BPDCN testing should include CD123, in combination with CD4 and CD56
* The diagnosis of BPDCN requires immunophenotyping and fundamentally relies on the demonstration of CD4, CD56, CD123, CD303, and TCL1 expression, together with a lack of expression of markers for B cells, T cells, myeloid or monocytic cells, and NK cells.4,10
Early and accurate diagnosis is critical to reach complete remission.5
Consider adding the CD123 marker to your hematologic diagnostic panels4,10,11
Abbreviations
AML = acute myeloid leukemia;
ATL/ATLL = adult T-cell leukemia/lymphoma;
BPDCN = blastic plasmacytoid dendritic cell neoplasm;
CD = cluster of differentiation;
CMML = chronic myelomonocytic leukemia;
CLL = chronic lymphocytic leukemia;
CTCL = cutaneous T-cell lymphoma;
DLBCL = diffuse large B-cell lymphoma;
MDS = myelodysplastic syndrome;
NK = natural killer;
pDC = plasmacytoid dendritic cell;
PTCL = peripheral T-cell lymphoma;
TCL1 = T-cell leukemia/lymphoma protein 1A;
WHO = World Health Organization.
References
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