What is langerhans cell histiocytosis (LCH)?
Langerhans cell histiocytosis (LCH) is a rare disorder that begins in LCH cells. LCH cells are a type of white blood cell called a dendritic cell that is usually involved in helping the body fight infection. They are in all parts of the body: the blood, bone, skin, liver, spleen and intestines.
Sometimes mutations (changes) develop in genes that control how these cells work. These include mutations or changes in the DNA of the BRAF, MAP2K1, RAS and ARAF genes. These changes/mutations may cause too many LCH cells to grow and build up in certain parts of the body, where they can damage tissue or form lesions.
What are the symptoms of langerhans cell histiocytosis?
Symptoms may include:
- Localized pain
- Bone lesions
- Swelling or a bump/mass over a bone that is affected
- Fractures, particularly when the tumor is in a weight-bearing bone
- Spine issues such as painful scoliosis or kyphosis
- Enlarged liver or spleen
- Diabetes insipidus
- Skin issues, including a skin rash or cradle cap (a scalp rash often in infants)
- Ear pain or recurring ear infections
- Low-grade fever
- Weight loss and tiredness
What causes LCH?
Causes of langerhans cell histiocytosis include:
- Having a parent who was exposed to certain solvents
- Having a parent who was exposed to metal, granite or wood dust in the workplace
- Having a family history of cancer or LCH
- Having a personal history or family history of thyroid disease
- Having infections as a newborn
- Smoking, especially in young adults
- Being of Hispanic descent
- Not being vaccinated as a child
How do you diagnose langerhans cell histiocytosis?
How we go about diagnosing LCH depends on the symptoms. We may use the following tests and procedures:
- A physical exam
- Blood counts are drawn and checked to look at all the blood cell types and numbers
- Blood chemistry and liver function will help determine the involvement of other organs
- BRAF gene testing: A laboratory test in which a sample of blood or tissue is tested for certain changes in the BRAF gene
- Urinalysis: looking at urine concentration
- Bone marrow aspiration and biopsy: The removal of bone marrow and a small piece of bone by inserting a hollow needle into the hipbone to look for LCH cells.
- X-rays of all the bones looking for any lesion: LCH can affect any bone and while often there is pain and/or swelling, sometimes there isn’t PET/CT and MRI of the brain can also be performed based on what areas are involved.
How do you treat LCH?
Children with LCH should have their treatment planned by a team of health care providers who are experts in treating childhood cancer or LCH. Our team of oncologists is here for you and your family to review treatment options and answer any questions you may have.
Treatment can include:
- Radiation therapy
- Photodynamic therapy
- Targeted therapy
- Other drug therapy
- Stem cell transplant
- New types of treatment that are tested in clinical trials
What are the outlook and long-term effects of this condition?
After treatment, our team monitors for many years to look for recurrence. We will run similar studies done at the time of diagnosis should we suspect we need to test.