Although leukemia primarily affects the blood, it can also leave its mark on the skin. In some cases, people with leukemia may develop noticeable skin changes such as lesions, bruises, rashes, and spots. Leukemia cutis is a rare dermatology condition that affects around 3 percent of people living with leukemia. In leukemia cutis, cancer cells affect the skin, resulting in bumps or discolored patches.

In this article, we describe what leukemia cutis is, how it develops, and what it means for your prognosis (outlook).

What Is Leukemia Cutis?

In leukemia cutis, leukemia cells spread to the skin or the layers just below the skin. These leukemia cells can be lymphoblasts, as with acute lymphoblastic leukemia, or myeloblasts, as with acute myeloid leukemia (AML). Leukemia begins when stem cells in the bone marrow, which normally create healthy blood cells, become abnormal. These defective stem cells don’t develop as they should, leading to leukemia cells that grow uncontrollably. Over time, these leukemia cells crowd out healthy blood cells, causing the symptoms of the disease.

Leukemia cutis isn’t usually the first symptom of leukemia. In most cases, leukemia cutis appears after someone has already been diagnosed with leukemia. When leukemia cutis is the first symptom, it’s called aleukemic leukemia.

Most of the time, leukemia cutis shows up as small papules (bumps) on the skin, but larger bumps, called nodules, can also appear. They are usually not painful and can be red or purple or 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 problems in people with leukemia are called leukemids. These skin lesions are not caused by leukemia cells invading the skin. They comprise about 40 percent of skin changes in leukemia and include rashes due to low platelet counts, infections, and side effects of medications.

AML is most commonly associated with leukemia cutis. About 10 percent to 15 percent of people with AML develop leukemia cutis, according to an article in the journal Cancers. Some types of AML are more likely to include leukemia cutis than others. For example, about 50 percent of people with AML develop leukemia cutis. Another rare type of cancer, adult T-cell leukemia/lymphoma, also increases the risk of getting leukemia cutis.

Although it’s rare to be born with leukemia, infants with the condition are more likely than adults to develop leukemia cutis. About 25 to 30 percent of these infants will experience this skin condition. In infants, leukemia cutis is sometimes called “blueberry muffin syndrome” because of the blue-purple dots that appear on the skin. On darker skin tones, these spots may look more like dark brown or grayish patches.

Leukemia cutis is least common in chronic types of leukemia, such as 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, treating just the skin isn’t considered effective.

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

Some cases of leukemia cutis are linked to leukemia that has either relapsed (returned after treatment) or is refractory (has not responded to treatment). Doctors often recommend different treatment options for relapsed and refractory leukemia from those used when cancer is first 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 can also help relieve the symptoms of leukemia cutis.

The Prognosis of Leukemia Cutis

Leukemia cutis is usually seen as a sign of a worse outlook for people with leukemia. One small study of 62 people with AML and leukemia cutis found that the five-year survival rate was 8.6 percent. This figure was compared to 28.3 percent in a similar group with AML but without leukemia cells affecting their skin.

Researchers are studying a new treatment for AML with leukemia cutis. A drug called Annamycin is used to treat AML that hasn’t responded to other treatments. It’s showing promising results in clinical trials, with some patients going into remission. More trials are being conducted in Europe, and there’s hope that one day leukemia cutis won’t be linked to 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 19,600 members come together to ask questions, give advice, and share their stories with others who understand life with leukemia.

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