Skip to content
How It Works
Explore
Ask a Question Resources Pricing
Who It's For
Patients
Decode results, prep for appointments, weigh options.
Caregivers & advocates
Carry the research load for someone you love.
Providers & clinicians
Resources for patients in your practice.
Log In Sign Up
PubMed This is a summary of 13 peer-reviewed journal articles Updated
Dermatology

What Do BPDCN Skin Lesions Look Like? Signs to Know

At a Glance

BPDCN skin lesions often look like persistent dark purple, plum-colored, or reddish-brown bruises. They may be flat patches, raised plaques, or firm nodules and can appear anywhere, but appearance alone cannot diagnose BPDCN; a skin biopsy and laboratory testing may be needed.

In this answer

4 sections

01

What Do the Lesions Look and Feel Like?

02

Where Do They Appear?

03

How Are They Diagnosed?

04

What to Do If You Notice Changes

The skin lesions of Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN) most commonly appear as dark purple, plum-colored (violaceous), or reddish-brown spots on the skin [1][2]. These lesions are often the very first sign of the disease [3][4]. While their appearance can vary from person to person, they often resemble bruises that remain persistent rather than fading away like normal bruises do [5].

It is important to remember that BPDCN is an extremely rare cancer. The vast majority of bruises or purple skin lesions are not BPDCN.

What Do the Lesions Look and Feel Like?

BPDCN skin involvement generally shows up in one of three main ways, and a person may have just a single lesion or many spread across their body [1][6]:

  • Bruise-like patches: Flat areas of discolored skin that may look like everyday bruises but do not change colors and fade away over time.
  • Plaques: Slightly raised, discolored, thickened areas of skin.
  • Nodules: Firm, raised, plum-colored or reddish-brown solid lumps on or just under the skin [2][5].

Unlike many other rashes or skin conditions, BPDCN lesions are usually asymptomatic—meaning they often do not itch, hurt, or cause discomfort [7][8]. However, for some people, they might feel slightly tender to the touch or be mildly itchy [9]. The presence or absence of symptoms cannot be used to diagnose BPDCN.

Where Do They Appear?

These spots can appear anywhere on the body [3]. They are most frequently reported on the:

  • Chest, back, and trunk
  • Arms and legs
  • Face and scalp [4][6]

Skin lesions can be the only noticeable sign of BPDCN at first, but the disease can also involve the blood, bone marrow, and lymph nodes.

How Are They Diagnosed?

Because BPDCN skin lesions look so much like ordinary bruises, benign skin conditions, or other cancers that affect the skin (such as leukemia cutis, which is when leukemia cells infiltrate the skin), doctors cannot diagnose the disease just by looking at them [10][11].

If BPDCN is suspected based on your skin spots, a skin biopsy is usually needed to confirm what the lesion is [12]. During a biopsy, a small sample of the lesion is removed for testing. A specialized doctor called a pathologist will look at the cells under a microscope and perform specific tests (called an immunophenotyping panel). They look for a specific combination of proteins (markers like CD4, CD56, CD123, and CD303) found on BPDCN cells [2][13]. No single marker is unique to BPDCN, which is why a full panel is required.

In some cases, BPDCN may be diagnosed from a blood or bone marrow sample instead of a skin biopsy if the disease is present in those areas.

What to Do If You Notice Changes

If you notice a new, unexplained, persistent, or enlarging bruise-like lesion, do not wait a set amount of time for it to fade before seeking medical advice. Contact your dermatologist or primary care doctor for an evaluation.

If you have already been diagnosed with BPDCN:

  • Contact your oncology team about any new or rapidly changing lesions.
  • Ask if you should photograph the lesions to track changes.
  • Follow your care team’s instructions for urgent symptoms like unexplained bleeding, high fever, or severe weakness.

Common questions in this guide

What colors and shapes can BPDCN skin lesions have?
They often appear dark purple, plum-colored, or reddish-brown and may resemble bruises that do not fade normally. They can be flat patches, slightly raised plaques, or firm nodules, and their appearance varies from person to person.
Do BPDCN skin lesions hurt or itch?
Most are not itchy or painful, but some people have mild itching or tenderness. Whether a lesion causes symptoms cannot confirm or rule out BPDCN.
Where do BPDCN skin lesions usually appear?
They can occur anywhere on the body, including the chest, back, trunk, arms, legs, face, and scalp. A person may have one lesion or many lesions spread across the skin.
Can a doctor diagnose BPDCN just by looking at a skin lesion?
No. BPDCN lesions can look like ordinary bruises, harmless skin conditions, or leukemia cutis, so a skin biopsy is usually needed. A pathologist examines the cells and uses a panel of protein tests; blood or bone marrow testing may sometimes be used instead.
When should I have a persistent purple or bruise-like spot checked?
Contact a dermatologist or primary care clinician about a new, unexplained, persistent, or enlarging bruise-like lesion rather than waiting for it to fade. If you already have BPDCN, tell your oncology team about new or rapidly changing lesions and follow their instructions for urgent symptoms.

Questions For You

Answer a question to get research tailored to you. Your answers are private.

Related questions

What Is BPDCN's Long-Term Outlook and Survival Rate? Why Is a BPDCN Transplant Recommended While in Remission? How Rare Is BPDCN? Incidence and Who Usually Gets It What Are Tagraxofusp's Common Non-CLS Side Effects in BPDCN? What Is the Pathophysiology of CLS During BPDCN Treatment?
Show more
How Do CD123, CD4, and CD56 Support BPDCN Diagnosis? How Is Capillary Leak Syndrome Managed During Tagraxofusp? What Intensive Chemotherapy Regimens Are Used for BPDCN? What Are the Early Signs of Acute and Chronic GVHD? Why Is BPDCN Frequently Misdiagnosed? Common Mimics What Do TET2, ASXL1, and ZRSR2 Mean in BPDCN NGS Results? What Is the Long-Term BPDCN Survivor Surveillance Schedule? How Does Tagraxofusp (Elzonris) Work Against BPDCN? What Do Plasmacytoid Dendritic Cells Do in Immunity? Which Slides and Reports Does a BPDCN Second Opinion Need? What Should I Ask My Oncologist About BPDCN Expertise? Why Might BPDCN Need Chemotherapy in the Spinal Fluid?

Get notified when new evidence is published on Blastic plasmacytoid dendritic cell neoplasm.

We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Are my skin spots behaving like typical bruises, or do they look suspicious for something else?
  2. 2.If we do a skin biopsy, will the sample be sent to a hematopathologist with experience in rare blood cancers?
  3. 3.What specific panel of markers will the lab look for to help distinguish this from other skin or blood conditions?
  4. 4.How do my skin findings relate to the rest of my body, and will I need bloodwork or a bone marrow evaluation?
  5. 5.What changes in my skin should prompt a same-day call to the clinic?

References

References (13)
  1. 1

    Blastic Plasmacytoid Dendritic Cell Neoplasm: The Dermatologist's Perspective.

    Hirner JP, O'Malley JT, LeBoeuf NR

    Hematology/oncology clinics of North America 2020; (34(3)):501-509 doi:10.1016/j.hoc.2020.01.001.

    PMID: 32336415
  2. 2

    Blastic Plasmacytoid Dendritic Cell Neoplasm: A Single-Center Experience. Clinical Characterization, Mutational Landscape, and Clinical Outcome of Patients Undergoing Hematopoietic Stem Cell Transplantation Intensive Therapy.

    Gil-Lianes J, Mozas P, Baumann T, et al.

    Actas dermo-sifiliograficas 2025; (116(2)):169-175 doi:10.1016/j.ad.2023.09.029.

    PMID: 38852841
  3. 3

    Blastic plasmacytoid dendritic cell neoplasm in a young patient.

    Li JN, Harker D, Vandergriff T, Dominguez A

    Dermatology online journal 2021; (27(1)).

    PMID: 33560790
  4. 4

    Blastic Plasmacytoid Dendritic Cell Neoplasm Presenting With Bruise-Like Macules: Case Report and Literature Review.

    Bai J, Wang S, Fang H, Qiao J

    Pediatric dermatology 2025; (42(5)):1058-1061 doi:10.1111/pde.15931.

    PMID: 40454522
  5. 5

    Blastic Plasmacytoid Dendritic Cell Neoplasm: A Case Series and Review.

    Adnan A, Powell PR, Staples CJ, et al.

    The American Journal of dermatopathology 2021; doi:10.1097/DAD.0000000000001968.

    PMID: 33989217
  6. 6

    Blastic plasmacytoid dendritic cell neoplasm: a short review and update.

    Massone C, Rivoli G, Sola S, Angelucci E

    Dermatology reports 2024; (16(Suppl 2)):9781 doi:10.4081/dr.2023.9781.

    PMID: 39295884
  7. 7

    Blastic plasmacytoid dendritic cell neoplasm: update on therapy especially novel agents.

    Wang S, Wang X, Liu M, Bai O

    Annals of hematology 2018; (97(4)):563-572 doi:10.1007/s00277-018-3259-z.

    PMID: 29455234
  8. 8

    A rare case of blastic plasmacytoid dendritic cell neoplasm with deletion 7q.31, in the setting of heavy pre-treatment with alkylating chemotherapy.

    Kaur V, Swami A, Shebli A, et al.

    Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners 2017; (23(7)):552-556 doi:10.1177/1078155216665245.

    PMID: 27559020
  9. 9

    Skin lesions serve as clues to relapse of pediatric blastic plasmacytoid dendritic cell neoplasm.

    Dreyer S, Mednik S, Truong A, et al.

    Pediatric dermatology 2018; (35(2)):e132-e135 doi:10.1111/pde.13426.

    PMID: 29436012
  10. 10

    Blastic plasmacytoid dendritic cell neoplasm.

    Flynn EN, Dadras SS, Petty A, et al.

    Dermatology online journal 2025; (31(1)) doi:10.5070/D331164962.

    PMID: 40526931
  11. 11

    NPM1 -Mutated Myeloid Sarcoma/Leukemia Cutis Mimicking Blastic Plasmacytoid Dendritic Cell Neoplasm and Heralding Bone Marrow Acute Myeloid Leukemia.

    Hu AY, Wang X, Jorgensen J, et al.

    The American Journal of dermatopathology 2026; (48(3)):221-225 doi:10.1097/DAD.0000000000003205.

    PMID: 41468560
  12. 12

    Blastic plasmacytoid dendritic cell neoplasm of skin, a rare dermatohematologic malignancy-A case report.

    Edjtemaei R, Ghanadan A, Ameli F

    Clinical case reports 2024; (12(9)):e9398 doi:10.1002/ccr3.9398.

    PMID: 39210931
  13. 13

    Acute Myeloid Leukemia With Plasmacytoid Differentiating Cutaneous Lesions: A Case of Double Identity or Active Transformation.

    Lee BJ, Griffin SP, Jeyakumar D, et al.

    EJHaem 2026; (7(1)):e70221 doi:10.1002/jha2.70221.

    PMID: 41613949

This page is for informational purposes only and does not replace medical advice. A dermatologist or oncology team must evaluate persistent lesions; only a biopsy and appropriate testing can determine their cause.