BPDCN and Leukemia: What’s the Difference?

There are many different types of leukemia, including acute lymphocytic leukemia, acute myeloid leukemia, and chronic lymphocytic leukemia, to name a few. Leukemia is most often recognized as a cancer of the white blood cells, caused by the rapid production of abnormal white blood cells. While leukemia is a well-known form of blood cancer, an aggressive and rare form of blood cancer, plastic plasmacytoid dendritic neoplasm (BPDCN), is often mistaken for leukemia.¹

BPDCN was previously known as natural killer (NK) cell leukemia/lymphoma before its biology and origin were understood. In 2008, the World Health Organization (WHO) established the term “BPDCN.” WHO gave BPDCN its own category in the 2016 WHO revision. Due to little data on BPDCN, there is no established treatment, and it is commonly misdiagnosed as leukemia or lymphoma.²

Signs and symptoms of BPDCN include:

• Swollen lymph nodes
• Stomach pain
• Fatigue
• Skin lesions (presenting as a rash or bruises)

Approximately 80% of BPDCN cases involve the skin as the site of the disease. BPDCN also progresses with bone marrow involvement and a decrease in red blood cells, white blood cells, and platelet counts. The average age of diagnosis is 60-70 years old. ²

While the signs and symptoms of BPDCN are very similar to other forms of cancers, health care providers can biopsy skin, lymph nodes, or bone marrow to look for CD123, a type of protein specifically found in BPDCN cells.³

Leukemia symptoms can vary depending on the type of leukemia, but the most common signs and symptoms include:

• Fever or chills
• Fatigue
• Easy bleeding or bruising
• Petechiae of the skin (red spots)
• Bone pain or tenderness

BPDCN is commonly misdiagnosed as acute myeloid leukemia (AML), a rare blood cancer that accounts for 1% of all new cancer cases. AML starts in the blood and bone marrow and can progress rapidly, with relapse affecting approximately 50% of all patients. Many treatment options can lead to a long-term reduction in symptoms, but without immediate treatment, AML becomes increasingly difficult to manage. The median age of diagnosis is 68, similar to BPDCN,^1,2 which has overlapping symptoms to AML, including bruises, fatigue, weakness, and excessive bleeding.¹

While the difference between BPDCN and leukemia is increasingly difficult to spot, BPDCN presents more on the skin as lesions and bruising, and the protein CD123 can be detected specifically in BPDCN cells through biopsying.

References

1. Types of leukemia. Leukemia Research Foundation. Accessed November 22, 2022. https://leukemiarf.org/leukemia/
2. Blastic plasmacytoid dendritic cell neoplasm. Leukemia & lymphoma society. Accessed November 2022, 2022. https://www.lls.org/leukemia/blastic-plasmacytoid-dendritic-cell-neoplasm
3. Signs and symptoms of BPDCN. Stemline. Accessed November 22, 2022. https://www.elzonris.com/diagnosis#:~:text=Common%20signs%20and%20symptoms%20of,like%20marks%20on%20their%20skin.&text=Nodular%20lesions%2C%20or%20an%20abnormal,appear%20anywhere%20on%20the%20body.