Café-au-lait macules (CALMs)

What are café-au-lait macules?

Café-au-lait macules (CALMs), or café-au-lait spots, are flat, oval lesions (marks) on the skin. Café-au-lait means "coffee with milk" in French. The name refers to the colour of the spots, as they are at least a shade darker than your child’s skin tone.

Café-au-lait macules commonly appear at birth but may develop later, during the first year of life. Their colour varies from light brown to dark brown.

How do CALMs affect the body?

CALMs are benign (harmless). They do not hurt or itch and never progress to anything serious such as skin cancer. The spots can become darker throughout childhood or with sun exposure, but this is not a cause for concern.

How common are CALMs?

The size and number of café-au-lait macules vary from child to child. About one in five healthy children have one or two CALMs. Up to one in 100 children have three CALMs.

How are CALMs diagnosed?

CALMs are easily diagnosed by a skin examination. "Typical" CALMs range from light to dark brown and are well defined, even coloured and often round or oval. They vary in size and can appear anywhere on the skin, although they rarely appear on the face.

How are CALMs treated?

No therapy is needed for CALMs. If your child is concerned about how their CALMs look, you can consider covering the CALMs with camouflage make-up to make them less noticeable. Some people consider laser treatment to reduce the colour, but this is painful and expensive. It also carries side effects and may not be very effective in reducing the colour of the CALMs.

Are CALMs ever a feature of another condition?

CALMs can sometimes indicate an underlying genetic disorder. See your child’s doctor if your child has:

• six or more CALMs measuring more than 5 mm before puberty
• six or more CALMs measuring more than 15 mm during puberty

If a genetic disorder is present, tiny CALMs, which look like freckles, may be visible under the arms or around the groin.

The most common genetic disorder linked with multiple CALMs is neurofibromatosis type 1 (NF-1). Other conditions with CALMs as a symptom include McCune-Albright syndrome, tuberous sclerosis, Noonan syndrome, Legious syndrome and Fanconi anaemia.

When to see a doctor for CALMs

See your child’s doctor or dermatologist if your child has:

• an undiagnosed pigmented lesion
• more than six café-au-lait macules measuring more than 5mm before puberty or more than 15 mm after puberty
  
• freckling around the armpit or groin
• CALMs with lumps and bumps on the skin
• other family members with multiple CALMs or a diagnosis of NF-1
• many CALMs with any learning problems or speech, language or other developmental delays
  

​Further information

Children's Tumor Foundation

Dermnet New Zealand Trust: Facts about the skin

Neurofibromatosis Society of Ontario