Hodgkin lymphoma is a type of cancer that affects the lymphatic system. This highly sophisticated filtering system helps the body's immune system remove bacteria, viruses, and other unwanted substances.
The lymphatic system includes the lymph nodes (glands), thymus, spleen, tonsils, adenoids, and bone marrow, as well as the channels (called lymphatics or lymph vessels) that connect them. When lymphoma happens, cancer cells develop in a person's lymphatic system and start to grow uncontrollably.
The different types of lymphomas are grouped into two broad categories: Hodgkin lymphoma and non-Hodgkin lymphoma. Lymphomas that involve a type of cell known as a Reed-Sternberg cell are classified as Hodgkin lymphoma. The different subtypes of Hodgkin lymphoma are classified based on how the cancerous tissue looks under a microscope.
Age is a risk fact for Hodgkin lymphoma — it tends to mostly affect teens and people older than 55. It also can happen in people with severe immune deficiencies from things such as inherited immune defects, human immunodeficiency virus (HIV) infection, treatment with immunosuppressive drugs after organ transplants, or Epstein-Barr virus.
Usually, the causes of lymphoma are unknown and no lifestyle factors have been definitely linked to childhood lymphomas.
So, neither parents nor kids have control over the things that cause the disease. Most lymphomas come from noninherited mutations (errors) in the genes of growing blood cells. However, there is a very slightly increased risk of Hodgkin lymphoma if other family members have had the disease. Regular pediatric checkups can sometimes spot early symptoms of lymphoma.
The most common first symptom of Hodgkin lymphoma is a painless enlargement of the lymph nodes (often called "swollen glands") in the neck, the underarm area, or the groin.
If cancer involves the lymph nodes in the chest, pressure may trigger an unexplained cough, shortness of breath, or problems in blood flow to and from the heart.
About a third of patients have other nonspecific symptoms, including fatigue (tiredness), poor appetite, itching, or a rash. Unexplained fever, night sweats, and weight loss are also common. Many patients have no other symptoms at all.
One of the things doctors might look for if they suspect lymphoma is enlargement of the lymph nodes. They may first try to treat swollen lymph nodes with antibiotics, because infections are the most common cause of this.
But if the lymph nodes stay swollen, a child may be referred to an oncologist (cancer doctor), who might recommend imaging studies and a biopsy (tissue sample) of the lymph nodes.
During a biopsy, a tiny bit of tissue is removed from the body and sent out to a laboratory for analysis. If Hodgkin lymphoma is suspected, one of these biopsies may be done:
Core biopsy: the doctor uses a hollow needle to remove a small amount of tissue from the lymph node.
Excisional biopsy or incisional biopsy: the doctor opens the skin to remove the entire enlarged lymph node (excisional) or only part of it (incisional).
Depending on the type of biopsy ordered, the doctor might use local anesthesia (where only a part of the body is numbed) or, most commonly, general anesthesia (in which a patient is asleep) to ensure there is no pain.
If the doctor suspects Hodgkin lymphoma, more tests will be done to see if the cancer has spread. These can include:
a chest X-ray
a computed tomography (CT or CAT) scan, a type of X-ray that rotates around the patient and creates a picture of the inside of the body from different angles
a bone marrow biopsy to check for cancer in the bone marrow
a positron emission tomography (PET) scan, which can tell the difference between normal and abnormal cells
Treatment for Hodgkin lymphoma is very effective for most kids. The choice of treatment is largely determined by staging. Staging is a way to categorize or classify patients according to how extensive the disease is at the time of diagnosis.
There are four stages of lymphoma, ranging from Stage I (cancer involving only one area of lymph nodes or only one organ outside the lymph nodes) to Stage IV (cancer has spread, or metastasized, to one or more tissues or organs outside the lymphatic system). The stage at diagnosis can help medical professionals choose the best therapy and predict how someone with lymphoma will do in the long term.
Treatment may involve radiation (the use of high-energy rays to shrink tumors and keep cancer cells from growing), chemotherapy (the use of highly potent medical drugs to kill cancer cells), or both, depending on the type and stage of the cancer as well as the age and overall health of the child.
For children whose cancer comes back after treatment or who do not respond well to treatment, doctors may do stem cell transplants (also called bone marrow transplants) to replace cells damaged by chemotherapy or radiation. These transplants involve taking the cells from bone marrow or blood (either taken from the patient or donated by another person) and transplanting them to the patient after chemo. There are also some very effective drugs that have helped improve the chances of a cure.
Researchers are constantly working on new treatments for cancer. Some parents enroll their child in clinical trials, which are ways to test new cancer treatments or compare their effectiveness with existing treatments. If your child has Hodgkin lymphoma, the doctor can tell you whether this is a good idea for the particular type he or she has.
Short-Term and Long-Term Side Effects
Treatment for Hodgkin lymphoma is powerful. It destroys good cells along with bad, which can create certain side effects.
Intensive lymphoma treatment affects the bone marrow, causing anemia and easy bleeding, and increasing the risk for serious infections. Chemotherapy treatments have side effects — some short-term (such as hair loss, increased infection risk, and nausea and vomiting) and some long-term (such as heart, thyroid, and kidney damage, reproductive problems, or the development of another cancer later in life) — that parents should discuss with the doctor.
The majority of kids with Hodgkin lymphoma are cured, meaning they will have long-term cancer-free survival. However, those with higher-stage disease are at risk for more long-term side effects as a result of more intensive treatment.
After treatment is finished, it's important for anyone who has had Hodgkin lymphoma to have regular checkups throughout life to watch for recurrence of the lymphoma and for late side effects of treatment.