What is Hodgkin lymphoma in children?
Hodgkin lymphoma in children starts in the lymphatic system, the network of vessels that run through the body and carry fluid that contains white blood and other important cells of the immune system. Lymph nodes respond to infections by releasing white blood cells called lymphoid cells into the bloodstream to fight them. When someone has lymphoma, many abnormal lymphoid cells or lymphomas are produced within a particular lymph node.
These are the same cells that become cancerous in people who have leukemia, another form of blood cancer. The difference is that leukemia develops in the bone marrow and affects the normal production of blood cells. Lymphoma, on the other hand, develops in the lymphatic system and does not affect the normal production of blood cells.
In patients with lymphoma, cancer cells clump together in the lymph nodes and form tumors. These cells can also spread to the bloodstream and spread cancer throughout the body, including to other lymph nodes.
Hodgkin lymphoma tends to affect the lymph nodes in the head and neck, while Non-Hodgkin lymphoma can affect any lymph node or related tissue in the body.
Causes of Hodgkin lymphoma in children
Normally speaking, childhood cancer, like adult cancer, is caused by the uncontrolled repetition of our body’s own cells. In a healthy body, cells grow and divide only when necessary to replace old or damaged cells. When cancer develops, old cells do not die, and/or new cells grow when they are not needed.
As these new cells divide without stopping, they can develop into a tumor or another form of cancer. Hodgkin lymphoma in children, which accounts for about 6% of all childhood cancers diagnosed in the United States, is a form of cancer that usually begins in white blood cells that the body uses to fight viruses, bacteria, and other foreign invaders.
Symptoms of Hodgkin lymphoma in children
Hodgkin lymphoma in children is a cancer of the lymphatic system, the most common symptom is one or more swollen lymph nodes. Lymph nodes are bean-sized clusters of lymphatic tissue in the neck, armpit, chest, and groin. A lump in one of these areas that does not go away over time increases in size, and/or spreads to additional areas of the body can be an indicator of Hodgkin lymphoma in children.
Swollen lymph nodes caused by Hodgkin lymphoma in children are usually not painful or uncomfortable. However, swollen lymph nodes in the chest can press on the lungs and/or windpipe (windpipe), causing coughing or shortness of breath, especially when lying down.
However, it is important to note that most swollen lymph nodes are caused by infection, Non-Hodgkin lymphoma, as the lymph nodes are responsible for filtering the lymph in the blood responsible for fighting viruses and bacteria in the body. Swollen lymph nodes caused by an infection are usually uncomfortable or painful to the touch and will return to normal size once the infection is under control.
Other symptoms of childhood Hodgkin lymphoma include:
- Skin itch
- General fatigue
- Fever of unknown cause (not related to infection)
- Unexplained weight loss/anorexia (10% of body weight in the 6 months before diagnosis)
- Night sweats
Three of these symptoms (unexplained fever, unexplained weight loss, and deep night sweats) are classified as B symptoms and are used to determine the “stage” of the disease as well as to assign risk. In general, patients with B symptoms are at higher risk and therefore require a more intensive treatment protocol.
The different types of childhood cancers:
- Childhood brain tumor cancer (brain stem tumors)
- Spinal cord tumor cancer
- Childhood neuroblastoma cancers
- Hodgkin Lymphoma Cancers
- Non-Hodgkin lymphoma cancers
- Wilms tumor (kidney tumors)
- Bone cancer (including osteosarcoma and Ewing’s sarcoma)
- Leukemia cancers: Acute lymphocytic (lymphoblastic) leukemia (ALL), Acute myelogenous leukemia (AML), and Juvenile myelomonocytic leukemia (JMML)
- Hepatoblastoma (liver cancer)
- Rhabdoid tumors
Diagnosis of Hodgkin lymphoma in children
Symptoms of Hodgkin lymphoma in children include persistent swelling (lasting a few weeks) of a single lymph gland, usually in the neck, armpit, or groin. Coughing or shortness of breath may occur if the glands in the chest are affected. Fever, sweating, itching, and weight loss can also occur. The exact diagnosis will be established by removing part or all of an affected lymph gland so that the cells can be inspected in the laboratory.
This is known as a biopsy and is usually done under general anesthesia. More tests, such as X-rays, CT scans, and MRIs, and Blood tests are done to determine the exact size and position of the lymphoma and whether it has spread. This is known as staging.
Hodgkin lymphoma can be defined as stages 1, 2, 3, or 4, followed by A or B.
- Stage 1: One area of the lymph nodes is affected in one place (either above or below the diaphragm, the muscle that separates the chest cavity from the abdominal cavity).
- Stage 2: Indicates that two or more areas are affected but, again, only above or below the diaphragm.
- Stage 3: Involves the lymph nodes above and below the diaphragm and possibly the spleen as well.
- Stage 4: Hodgkin lymphoma is the worst stage because it means that cancer has spread (to the liver, lungs, or bone marrow).
- A or B: Is added to the number to indicate if there are symptoms of systemic Hodgkin lymphoma (fever, weight loss, night sweats). A is used when there are none of these symptoms. B means that the symptoms are present and this implies that the child is worse and needs more treatment.
Treatment for Hodgkin lymphoma in children
The main treatment for Hodgkin lymphoma is chemotherapy. Radiation therapy is also sometimes required. If cancer has not spread beyond its original site, radiation therapy alone may be used after surgery to remove the affected lymph nodes. The type and amount of treatment given depend on the stage of the disease at the time of diagnosis.
When chemotherapy is used, it is usually given every few weeks for several months.
When radiation therapy is used, it is usually given for a few minutes each day for a period of two to four weeks. Treatment can last from a few months to two years, liable on the exact type of lymphoma and the stage to which it has proceeded.
Side effects and complications of Hodgkin lymphoma in children
Treatment of Hodgkin lymphoma often causes side effects. These will depend on the particular treatment used and the part of the body being treated, but may include:
- Hair loss
- Reduced resistance to infection
- Bruising and bleeding
A small number of children can develop late side effects, sometimes many years later, caused by lymphoma treatment. The main risks arise from the use of radiation therapy, which can affect growth and cause infertility. The risk of infertility is higher among children and the risk increases if both radiation therapy and chemotherapy are used. There is a risk of hypothyroidism associated with irradiation to the neck.
Both radiation therapy and chemotherapy have been associated with heart and lung complications. There is an increased risk of second cancers in those who survive childhood cancer, which is believed to be associated with the treatments used.
Your child’s doctor will explain the possible risks of any given treatment before starting treatment. Every effort will be made to minimize the risk of these types of complications.
Non-Hodgkin lymphoma be prevented?
Most children diagnosed with Non-Hodgkin lymphoma have no risk factors or lifestyle issues that could have been changed in any way to avoid the development of this disease. While it is entirely natural and very common to search for a cause or somewhat to blame when a child is diagnosed with NHL (or any type of cancer), parents and guardians must know that there is nothing that they could have done differently to prevent this disease.
There are two notable exceptions. First, a small percentage of diagnoses are associated with a compromised immune system such as HIV infection. HIV-positive mothers are refreshed to take active steps during and after pregnancy to reduce the risk of temporary HIV along to their children.
Second, NHL may develop as second cancer stopping from a prior cancer treatment or immune-suppressing drugs taken to enable an organ transplant. Clearly, in these cases, the small risk of developing NHL in the future must be weighed against the need to treat a possibly life-threatening disease in the present.