Although leukemia is a cancer of the blood, people with the condition can develop dermal (skin) symptoms, such as lesions, bruises, rashes, and spots. For example, leukemia cutis is a rare dermatology condition that affects around 3 percent of people living with leukemia. In leukemic cutis, cancer cells affect the skin, resulting in bumps or discolored patches.

Here, we describe what it is, how it develops, and what it means for your prognosis.

What Is Leukemia Cutis?

In leukemia cutis, leukemic cells infiltrate the skin or the subcutaneous layers beneath the skin. These leukemia cells can be lymphoblasts, as with acute lymphoblastic leukemia, or myeloblasts, as with acute myeloid leukemia (AML). All leukemia cells originate as defective stem cells in the bone marrow.

Leukemia cutis generally isn’t a first symptom of leukemia. Most cases occur after a diagnosis. When it does appear as a first symptom, it’s called aleukemic leukemia.

Most of the time, leukemia cutis presents as small papules (bumps) on the skin, but larger bumps, called nodules, can also appear. They are usually not painful, and they can be red or purple, or they can be the same color as your skin. People with AML may experience profuse bleeding, which can cause bruising.

How Common Is Leukemia Cutis?

While the skin is the third most common place for leukemic involvement — after the blood and bone marrow — leukemia cutis is a rare condition. Only about 3 percent of people living with leukemia will develop leukemia cutis. Most skin complications of leukemia are leukemids, lesions that are unrelated to leukemic infiltration of the skin.

AML is the form of leukemia that’s most commonly associated with leukemia cutis. Among people with AML, the prevalence of leukemia cutis is around 10 percent to 15 percent. Some types of AML are more likely to include leukemia cutis than others. For example, acute myelomonocytic leukemia has a 50 percent rate of leukemia cutis. The very rare adult T-cell leukemia/lymphoma is also associated with an increased incidence — or risk of developing — leukemia cutis.

Infants with congenital leukemia are more likely than adults to have leukemia cutis; around 25 percent to 30 percent will develop it. In infants, leukemia cutis is sometimes called “blueberry muffin syndrome” because of the blue-purple dots that appear on the skin.

Leukemia cutis is rarest in chronic leukemias, like chronic myeloid leukemia and chronic lymphocytic leukemia. Not all cases of leukemia cutis result from leukemia — people with other blood cancers such as myelodysplastic syndrome and myeloma can also develop leukemia cutis. Additionally, some evidence suggests that certain chromosome abnormalities in cancer cells are associated with a higher rate of leukemia cutis.

Early Leukemia Cutis

Leukemia cutis often appears in individuals who’ve been living with leukemia for months or even years. However, in 7 percent of cases, leukemia cutis is the first symptom of leukemia.

In its earliest stages, leukemia cutis may appear as a variety of different dermatological conditions. It may develop as:

• Papules — Firm, small bumps
• Nodules— Medium-size bumps
• Plaques — Large patches

These markings can appear red, brown, or purple in adults and blue in babies. The texture of affected skin may become dry and thickened, such as in eczema.

You may also experience ulcers or blisters in your mouth and gums, along with bleeding and irritation.

Where Does Leukemia Cutis Start?

Most of the time, these markings will first appear around the head, neck, abdomen, and back. Leukemia cutis is also likely to occur at a site of injury, such as around a recent accidental wound or even at an injection site.

Diagnosing Leukemia Cutis

Leukemia cutis skin symptoms usually aren’t itchy or sore in the beginning, so you may not even notice them right away. That’s why it’s important to inspect your skin regularly to catch cutaneous symptoms early on. If you experience new symptoms such as those described above, schedule an appointment with your oncologist and dermatologist to discuss how to receive a diagnosis.

If your oncologist suspects you have leukemia cutis, they’ll schedule you for a follow-up appointment with a dermatologist, who can perform a diagnostic skin biopsy. This entails having a small portion of skin from the affected area removed for analysis. A skin biopsy is crucial for determining whether your symptoms are leukemia cutis, another leukemia-related skin condition, or an unrelated dermatologic problem.

How Is Leukemia Cutis Treated?

Treatment of leukemia cutis is led by your oncology team, with a focus on treating the underlying leukemia. Because leukemia cutis is a sign of a malignancy that can affect other parts of the body, dermatological treatment of the skin alone isn’t considered effective.

As with many forms of leukemia, chemotherapy is the first line of treatment. For people who’ve recently been diagnosed with leukemia, treatment can begin with induction chemotherapy, where an intensive medication course is administered. Along with chemotherapy, a person may also receive localized radiation or undergo surgery on the skin to address leukemia cutis lesions.

Some cases of leukemia cutis are associated with relapsed (return of cancer cells after treatment) or refractory (does not respond to treatment) leukemia. Doctors often recommend different treatment options for relapsed and refractory leukemia from those used when cancer is initially diagnosed.

One approach to managing leukemia cutis that isn’t focused on the leukemia itself is the use of antimicrobials to prevent skin infection. These are medications such as antibiotics and antivirals that can prevent and treat infections. Topical steroids and lidocaine mixtures are also considered helpful to ease leukemia cutis symptoms.

The Prognosis of Leukemia Cutis

Leukemia cutis is usually considered to be a poor prognostic sign for people living with leukemia. One small study on 62 people with AML and leukemia cutis found a five-year survival rate of 8.6 percent, compared to 28.3 percent from a matched group with AML but no infiltration of the skin.

Researchers are investigating a treatment of AML with leukemia cutis. Annamycin, a drug used to treat relapsed or refractory AML, is showing promising results in clinical trials that include substantial remission. More clinical trials are underway in Europe. Hopefully, one day leukemia cutis will no longer be associated with a poor prognosis.

Talk to Others Who Understand

MyLeukemiaTeam is the social network for people with leukemia and their loved ones. On MyLeukemiaTeam, more than 12,600 members come together to ask questions, give advice, and share their stories with others who understand life with leukemia.

Have you experienced rashes or skin changes with leukemia? Have you been diagnosed with leukemia cutis? Share your experiences in a comment below or on MyLeukemiaTeam.