Leukemia is a type of cancer that affects the blood and bone marrow. People with leukemia may have skin-related issues, such as a rash or bruising.

When a person has leukemia, their body produces too many white blood cells. As they continue to grow, they crowd out the other cells in the blood, such as the red blood cells and platelets.

These changes can lead to various skin symptoms. Treatment for leukemia can also affect the skin.

Skin symptoms that can occur with leukemia include:

This article looks at some skin changes that can occur with leukemia, how to identify them, and which treatment, if any, may help.

The following images show some ways in which leukemia can affect the skin. More detail is below.

Here are some of the skin rashes and symptoms a person may experience with leukemia.

Petechiae and purpura

Petechiae are tiny spots that happen when small blood vessels called capillaries break under the skin. They are less than 2 millimeters across. Larger areas are known as purpura.

Petechiae and purpura can be early signs of leukemia, although they may happen for many other reasons.

Leukemia disrupts the production of platelets, which usually enable blood to clot. As platelet levels fall, it becomes harder for them to block any burst capillaries. As a result, the blood can leak out into the skin.

Petechiae and purpura may appear red, purple, or brown. On darker skin, they can be harder to spot, but they may be easier to see on lighter areas, for example, the soles of the feet or palms of the hands.

To distinguish petechiae from a skin rash, a person can press down on the affected area using a finger or thumb. Petechiae and purpura will not change color, but a rash will turn white.

Petechiae and purpura do not need specific treatment.

Easy bruising

Easy bruising and bleeding are common symptoms of leukemia. A person may notice them before they receive a diagnosis.

Bruises are common after an injury, but they may be a sign of leukemia if:

  • they happen even after a small knock, or a person cannot remember doing anything to cause them
  • they appear in unusual places, such as the back or hands
  • there are many bruises, or they happen often
  • they take longer than usual to disappear
  • they occur along with easy bleeding

As with petechiae, the body cannot prevent blood vessels from bleeding under the skin when an injury occurs. However, these bruises are different from petechiae. They look like regular bruises.

Why else might a person bleed easily?

Leukemia cutis

Leukemia cutis can occur in the later stages of leukemia. It is more likely with chronic lymphocytic leukemia and acute myeloid leukemia (AML) but can occur with other types.

The skin develops small bumps that look like a rash.

A person may notice:

  • papules on the skin
  • nodules that feel firm or rubbery
  • plaques

In some cases, the following may occur:

  • erythema, which makes the skin look red or darker in color, depending on the person’s skin tone
  • erythroderma — a widespread skin inflammation that can be life threatening
  • skin ulcers
  • blistering

The lesions may be red, brown, yellow, blue, gray, or purple. On darker skin, they can be harder to see. As with petechiae and purpura, they may be more visible on lighter areas, such as the hands and feet.

With deeper lesions, the skin color may not change.

If chemotherapy and other treatments for leukemia are effective, the symptoms of leukemia cutis will disappear.

Easy bleeding

People with leukemia often bleed more easily than before. This is because the blood does not clot effectively due to low platelet levels.

The individual may notice:

Sweet syndrome

Sweet syndrome can occur with various health conditions, including leukemia and other cancers. Doctors do not know precisely why it occurs.

It can lead to:

  • inflamed plaques or nodules on the skin of varying sizes and in a pattern that is not symmetrical
  • pustular lesions, ulcers, and blisters
  • mouth ulcers, in some cases
  • fever
  • joint pain
  • fatigue
  • headache
  • eye inflammation

Skin changes can affect the face, neck, chest, and back. They are more likely in the upper extremities, such as the hands, but can also occur in the lower extremities.

Steroid treatment may help manage Sweet syndrome.

Mastocytosis

Mastocytosis is a rash that occurs with some types of leukemia. It happens when there is too much mast cell activity. Mast cells play a role in the immune system and are present in connective tissue.

The mast cells trigger the release of compounds that stimulate the blood vessels.

The symptoms can resemble those of an allergic reaction. They can affect all the body’s systems.

Skin symptoms include:

  • flushing
  • itching
  • a rash
  • swelling under the skin, known as angioedema

Anaphylaxis may also occur. This is a life threatening emergency in which an allergic reaction causes severe symptoms, including difficulty breathing.

Anaphylaxis is a severe allergic reaction that can be life threatening. The symptoms develop suddenly and include:

  • hives
  • swelling of the face or mouth
  • wheezing
  • fast, shallow breathing
  • a fast heart rate
  • clammy skin
  • anxiety or confusion
  • dizziness
  • vomiting
  • blue or white lips
  • fainting or loss of consciousness

If someone has these symptoms:

  1. Check whether they are carrying an epinephrine pen. If they are, follow the instructions on the side of the pen to use it.
  2. Dial 911 or the number of the nearest emergency department.
  3. Lay the person down from a standing position. If they have vomited, turn them onto their side.
  4. Stay with them until the emergency services arrive.

Some people may need more than one epinephrine injection. If the symptoms do not improve in 5–15 minutes, or they come back, use a second pen if the person has one.

There is no specific treatment for mastocytosis that occurs with leukemia. A doctor may prescribe antihistamines or other medications.

Mouth sores

Leukemia often causes mouth problems. Sores, oral infections, and other symptoms may be early signs of leukemia.

Oral symptoms of leukemia include:

  • swelling of the gums or in the cheeks
  • bleeding from the gums
  • mouth ulcers
  • petechiae in the mouth
  • paleness in the mucous membranes, such as inside the cheeks
  • reduced ability to move the jaw, known as trismus or lockjaw

Topical treatments and over-the-counter pain medications can help manage discomfort due to mouth sores. A doctor may recommend a medicated mouthwash. In some cases, steroids can help.

Pale skin

People with leukemia can also develop anemia.

This can cause the skin to appear pale or greyish if a person has darker skin.

Red blood cells contain a protein called hemoglobin, which carries oxygen from the lungs to the rest of the body. A reduction in hemoglobin lowers the amount of oxygen circulating in the body.

As well as paleness, this can lead to:

  • fatigue and weakness
  • body aches
  • difficulty breathing
  • faintness or dizziness
  • a rapid heartbeat

Anemia can happen for many reasons, including leukemia and treatments for leukemia, such as chemotherapy or radiation therapy.

A blood transfusion can boost red blood cells if anemia is severe.

Which skin symptoms can occur with AML?

In addition to a rash, leukemia can cause a range of symptoms, including:

  • easy bruising and bleeding
  • fever
  • frequent infections
  • anemia
  • bone or joint pain
  • fatigue and weakness
  • unexpected weight loss
  • breathlessness
  • pale skin
  • swollen lymph nodes, for instance, under the arms or in the neck or groin

Rashes and other skin problems can occur for many reasons.

However, a person should see a doctor if they:

  • are bleeding or bruising more easily than before
  • have purple patches on the skin that could be petechiae
  • start developing frequent mouth sores and other oral problems
  • have other symptoms, such as fatigue, that could indicate a problem

These may be early signs of leukemia.

A person should also contact their treatment team if they have a diagnosis of leukemia and are concerned about new skin symptoms.

Learn more about other possible causes of skin rashes here.

Here are some questions people often ask about leukemia skin symptoms.

What does a leukemia rash look like?

This will depend on the rash, but leukemia and other health conditions can cause tiny red spots called petechiae on the skin or purple areas called purpura. The patches will not disappear if a person presses on them.

What does leukemia bruising look like?

A person with leukemia may bruise more easily than before and in unusual places. They may also develop petechiae or purpura — red or purple patches that, like bruises, result from bleeding under the skin.

Is a rash a symptom of leukemia?

Petechiae and purpura can be the first sign of leukemia a person notices. However, they can also result from other conditions. People with leukemia can also be more prone to infections, including skin infections.

A wide range of factors can lead to a rash, easy bruising, and other skin symptoms. However, people with leukemia may be more susceptible to certain skin changes.

If a person notices new or unusual skin symptoms, they should seek medical advice. A doctor can often prescribe effective treatment for skin rashes, but they may also wish to see if there is an underlying cause.