Langerhans cell histiocytosis (LCH) is a rare, cancer-like condition. It happens when a person’s body makes too many immature Langerhans cells. These cells are a type of immune cell known as histiocytes. When these cells build up, they can form tumors or damage tissue, bone and organs.

Langerhans cell histiocytosis can show up anywhere in the body. It is most common in the skin and bones. It also can affect bone marrow, lymph nodes and organs, including the lungs, liver, brain and spleen.

The disease is more common in children than adults. It occurs in about one out of every 200,000 children. It’s most often diagnosed between the ages of 1 and 3.

Langerhans cell histiocytosis is the most common type of histiocytic disorder. These are conditions in which the body makes too many histiocyte cells. Other histiocytic disorders include juvenile xanthogranuloma (JXG), Rosai-Dorfman disease (RDD) and Erdheim-Chester disease (ECD).

Langerhans Cell Histiocytosis Causes

The causes of Langerhans cell histiocytosis are unknown. It is not an inherited condition.

Langerhans Cell Histiocytosis Symptoms

Symptoms of Langerhans cell histiocytosis can vary a lot, from mild to severe. The symptoms will depend on how advanced the disease is and which tissues and organs are affected. Not all children with LCH have the same symptoms.

Other health problems can cause these symptoms. That is why it’s important for a child with these symptoms to see a doctor to find out the potential cause.

Symptoms of LCH can include:

• Pain, swelling or a lump in a bone that does not go away
• Broken bone from a minor injury or for no obvious reason
• Loose teeth (when not expected) or swollen gums
• Ear infections, cysts in the ear or fluid draining from the ear
• Skin rash, such as on the scalp or buttocks
• Swollen lymph nodes (glands) on the neck
• Liver problems, which can include jaundice (yellowing of the skin or whites of the eyes), fluid in the belly, diarrhea or vomiting
• Bulging eyes or other eye problems
• Cough and trouble breathing
• Weight loss for no obvious reason
• Not gaining weight or growing normally
• Not wanting to eat or having problems feeding
• Needing to urinate more often than normal and being very thirsty
• Fever, fatigue and weakness

Langerhans Cell Histiocytosis Diagnosis

Doctors who specialize in cancer typically diagnose and treat Langerhans cell histiocytosis. To diagnose LCH, your child’s doctor will remove a small section of the affected area (a biopsy). Another doctor (pathologist) will perform tests on the biopsy and look for signs of disease.

The doctor may also ask your child to have a PET scan to determine if Langerhans cell histiocytosis is affecting other parts of the body.

Once the doctors confirm an LCH diagnosis, it’s important to have additional testing done such as DNA sequencing. This can help show which gene changes (mutations) in the Langerhans cells may be causing the disease.

These tests can help your child’s care team create a personalized treatment plan.

Langerhans Cell Histiocytosis Treatment

Not all patients with Langerhans cell histiocytosis need treatment. If the disease is limited to the skin or one bone lesion, it likely will go away on its own.

If Langerhans cell histiocytosis is affecting more than one part of your child’s body, the care team will recommend a personalized treatment plan. For example, your child will need treatment if we find the disease on the skin and the liver, or if we find multiple bone lesions.

The standard treatment for Langerhans cell histiocytosis is to use a combination of chemotherapy drugs. Chemotherapy is given through the veins (intravenously) and is usually done at an outpatient clinic.

Because this standard treatment doesn’t work for everyone, Cincinnati Children's offers an alternative, first-line therapy. It is an oral drug (either dabrafenib or trametinib) that blocks certain gene mutations that cause Langerhans cell histiocytosis. This “gene inhibitor” therapy, which was pioneered at Cincinnati Children’s, has been successful in 100% of patients. It does not cause the side effects of chemotherapy.

Langerhans Cell Histiocytosis Prognosis

Langerhans cell histiocytosis can be severe and difficult to treat when it involves the organs or bone marrow. Some patients can also develop long-term side effects, such as neurological problems, bone defects, hearing loss or stunted growth.

However, most Langerhans cell histiocytosis patients respond well to personalized treatment. Thanks to the gene inhibitor treatment offered at Cincinnati Children’s, Langerhans cell histiocytosis is no longer a life-threatening disease. In patients who have undergone this treatment at Cincinnati Children’s, all have responded positively. All patients have had fewer side effects than the standard chemotherapy treatment.