Langerhans cell histiocytosis is a type of cancer that can damage tissue or cause lesions to form in one or more places in the body.
Langerhans cell histiocytosis (LCH) is a rare cancer that begins in LCH cells (a type of dendritic cell which fights infection). Sometimes there are mutations (changes) in LCH cells as they form. These include mutations of the BRAF gene. These changes may make the LCH cells grow and multiply quickly. This causes LCH cells to build up in certain parts of the body, where they can damage tissue or form lesions.
LCH is not a disease of the Langerhans cells that normally occur in the skin.
LCH may occur at any age, but is most common in young children. Treatment of LCH in children is different from treatment of LCH in adults. The treatments for LCH in children and adults are described in separate sections of this summary.
Check the list of NCI-supported cancer clinical trials that are now accepting patients with childhood Langerhans cell histiocytosis. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your child's doctor about clinical trials that may be right for your child. General information about clinical trials is available from the NCI website.
Family history or having a parent who was exposed to certain chemicals may increase the risk of LCH.
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk with your doctor if you think you may be at risk. Risk factors for LCH include the following:
Tests that examine the organs and body systems where LCH may occur are used to detect (find) and diagnose LCH.
The following tests and procedures may be used to detect (find) and diagnose LCH or conditions caused by LCH:
The following tests may be done on the tissue that was removed:
The signs and symptoms of LCH depend on where it is in the body.
These and other signs and symptoms may be caused by LCH or by other conditions. Check with your doctor if you or your child have any of the following:
Skin and nails
LCH in infants may affect the skin only. In some cases, skin-only LCH may get worse over weeks or months and become a form called high-risk multisystem LCH.
In infants, signs or symptoms of LCH that affects the skin may include:
In children and adults, signs or symptoms of LCH that affects the skin and nails may include:
Signs or symptoms of LCH that affects the mouth may include:
Signs or symptoms of LCH that affects the bone may include:
Lymph nodes and thymus
Signs or symptoms of LCH that affects the lymph nodes or thymus may include:
Signs or symptoms of LCH that affects the pituitary gland may include:
Signs or symptoms of LCH that affects the thyroid may include:
Central nervous system (CNS)
Signs or symptoms of LCH that affects the CNS (brain and spinal cord) may include:
Liver and spleen
Signs or symptoms of LCH that affects the liver or spleen may include:
Signs or symptoms of LCH that affects the lung may include:
Signs or symptoms of LCH that affects the bone marrow may include:
There are different types of treatment for patients with Langerhans cell histiocytosis (LCH).
Different types of treatments are available for patients with LCH. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Whenever possible, patients should take part in a clinical trial in order to receive new types of treatment for LCH. Some clinical trials are open only to patients who have not started treatment.
Clinical trials are taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI website. Choosing the most appropriate treatment is a decision that ideally involves the patient, family, and health care team.
Children with LCH should have their treatment planned by a team of health care providers who are experts in treating childhood cancer.
Treatment will be overseen by a pediatric oncologist, a doctor who specializes in treating children with cancer. The pediatric oncologist works with other pediatric healthcare providers who are experts in treating children with LCH and who specialize in certain areas of medicine. These may include the following specialists:
Some cancer treatments cause side effects months or years after treatment for childhood cancer has ended.
Side effects from cancer treatment that begin during or after treatment and continue for months or years are called late effects. Late effects of cancer treatment may include the following:
Some late effects may be treated or controlled. It is important to talk with your child's doctors about the effects cancer treatment can have on your child. (See the PDQ summary on Late Effects of Treatment for Childhood Cancer for more information.)
Many patients with multisystem LCH have late effects caused by treatment or by the disease itself. These patients often have long-term health problems that affect their quality of life.
Nine types of standard treatment are used:
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly onto the skin or into the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy).
Chemotherapy agents given by injection or by mouth are used to treat LCH. Chemotherapy agents include vinblastine, cytarabine, cladribine, and methotrexate. Nitrogen mustard is a drug that is put directly on the skin to treat small LCH lesions.
Surgery may be used to remove LCH lesions and a small amount of nearby healthy tissue. Curettage is a type of surgery that uses a curette (a sharp, spoon-shaped tool) to scrape LCH cells from bone.
When there is severe liver or lung damage, the entire organ may be removed and replaced with a healthy liver or lung from a donor.
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. External radiation therapy uses a machine outside the body to send radiation toward the cancer. In LCH, a special lamp may be used to send ultraviolet B (UVB) radiation toward LCH skin lesions.
Photodynamic therapy is a cancer treatment that uses a drug and a certain type of laser light to kill cancer cells. A drug that is not active until it is exposed to light is injected into a vein. The drug collects more in cancer cells than in normal cells. For LCH, laser light is aimed at the skin and the drug becomes active and kills the cancer cells. Photodynamic therapy causes little damage to healthy tissue. Patients who have photodynamic therapy should not spend too much time in the sun.
In one type of photodynamic therapy, called psoralen and ultraviolet A (PUVA) therapy, the patient receives a drug called psoralen and then ultraviolet A radiation is directed to the skin.
Biologic therapy is a treatment that uses the patient’s immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body’s natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy.
Interferon is a type of biologic therapy used to treat LCH of the skin. Immunomodulators are also a type of biologic therapy. Thalidomide is an immunomodulator used to treat LCH.
Targeted therapy is a type of treatment that uses drugs or other substances to find and attack LCH cells without harming normal cells. Imatinib mesylate is a type of targeted therapy called a tyrosine kinase inhibitor. It stops blood stem cells from turning into dendritic cells that may become cancer cells. Other types of kinase inhibitors that affect cells with the BRAF gene, such as dabrafenib and vemurafenib, are being studied in clinical trials for LCH.
A family of genes, called ras genes, may cause cancer when they are mutated (changed). Ras genes make proteins that are involved in cell signaling pathways, cell growth, and cell death. Ras pathway inhibitors are a type of targeted therapy being studied in clinical trials. They block the actions of a mutated ras gene or its protein and may stop the growth of cancer.
Other drug therapy
Other drugs used to treat LCH include the following:
Stem cell transplant
Stem cell transplant is a method of giving chemotherapy and replacing blood-forming cells destroyed by the LCH treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient or a donor and are frozen and stored. After the chemotherapy is completed, the stored stem cells are thawed and given back to the patient through an infusion. These reinfused stem cells grow into (and restore) the body's blood cells.
Observation is closely monitoring a patient's condition without giving any treatment until signs or symptoms appear or change.
New types of treatment are being tested in clinical trials.
Information about clinical trials is available from the NCI website.
Patients may want to think about taking part in a clinical trial.
For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.
Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.
Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.
Patients can enter clinical trials before, during, or after starting their treatment.
Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.
Clinical trials are taking place in many parts of the country. See the Treatment Options for Childhood LCH and the Treatment Options for Adult LCH sections for links to current treatment clinical trials. These have been retrieved from NCI's clinical trials database.
When treatment of LCH stops, new lesions may appear or old lesions may come back.
Many patients with LCH get better with treatment. However, when treatment stops, new lesions may appear or old lesions may come back. This is called reactivation (recurrence) and may occur within one year after stopping treatment. Patients with multisystem disease are more likely to have a reactivation. More common sites of reactivation are bone, ears, or skin. Diabetes insipidus also may develop. Less common sites of reactivation include lymph nodes, bone marrow, spleen, liver, or lung. Some patients may have more than one reactivation over a number of years.
Follow-up tests may be needed.
Some of the tests that were done to diagnose LCH may be repeated. This is to see how well the treatment is working and if there are any new lesions. These tests may include:
Other tests that may be needed include:
Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.
Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.