Blastic plasmacytoid dendritic cell neoplasm (BPDCN) previously known as natural killer (NK) cell leukemia/lymphoma is a rare, clinically aggressive hematologic malignancy that most commonly manifests as cutaneous lesions with or without bone marrow involvement and leukemic dissemination.

Common misdiagnoses for BPDCN include non-Hodgkin lymphoma (NHL), acute myeloid leukemia (AML), leukemia cutis (a nonspecific term used for cutaneous [skin] manifestation of any type of leukemia), melanoma (a type of skin cancer), and lupus erythematosus (chronic inflammatory disease that occurs when your body's immune system attacks your own tissues and organs).

Diagnostic testing: Diagnosis of BPDCN is difficult and the condition is often misdiagnosed.

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  A history and physical exam;

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  Skin biopsy showing infiltration of medium-sized (i.e., immature) blast cells into the dermis; and

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  Bone marrow biopsy.

Physical findings: Individuals with BPDCN may present with:

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  Skin lesions (nodules, tumors, red or purple papules, bruise-like patches, and/or ulcers);

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  Swollen lymph nodes;

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  Hepatomegaly (enlarged liver);

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  Splenomegaly (enlarged spleen);

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  Anemia (decreased red blood cells);

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  Thrombocytopenia (abnormally low platelet level); and

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  Leukopenia (decreased white blood cells).

ICD-9: 202.9

ICD-10: C86.4

The skin is the most frequently involved site of disease. However, BPDCN usually progresses with bone marrow involvement and a decrease in red blood cell, white blood cell and platelet counts. The lymph nodes and spleen may also be involved. Rashes without symptoms can also occur.

Due to the high rates of recurrence following initial therapy and the short overall survival times of individuals with BPDCN, prognosis of the disease is poor.

The average age at diagnosis is 60 to 70 years.

Treatment sometimes includes therapies that are used for AML, acute lymphoblastic leukemia (ALL), or lymphoma.

The length for which a patient responds to these treatments is usually short. After a relapse, second remissions with conventional chemotherapy are difficult to achieve. Allogeneic hematopoietic stem cell transplant (allo-HCT), especially if offered in first remission, may result in longer remissions. The current recommendation is for BPDCN patients to be evaluated for an allo-HCT as soon as possible and to begin searching for a donor.

Other treatment regimens that include intrathecal chemotherapy and hematological stem cell transplantation in initial treatment regimens and newer non-chemotherapeutic drug treatments may improve this situation.

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  Skin biopsy showing infiltration of medium-sized (i.e. immature) blast cells into the dermis; and

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  Bone marrow biopsy.

Suggested Listings for Evaluation:

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