What is neuroblastoma?
A neuroblastoma is a malignant tumor that most frequently occurs in children under five years of age. It is the most common malignant abdominal tumor seen in children.
Neuroblastoma arises from neural crest cells that may be in the adrenal gland (just above the kidney) or sympathetic nervous tissue. A neuroblastoma may be located anywhere that sympathetic nervous tissue is found. Most frequently a neuroblastoma is seen in the abdomen, chest, neck or pelvis. The cause of neuroblastoma is not known. It is not contagious, and nothing you have done or not done is responsible for your child's tumor.
What are the symptoms of neuroblastoma?
Because the site of the tumor can vary, the symptoms of the disease may vary. Often the tumor is felt while a parent is bathing or dressing a child or during a routine visit to the doctor. There could be other signs; if the tumor is in the pelvis it could press on the bladder, making it difficult for the child to urinate. In the chest, the tumor may cause a persistent cough, difficulty in breathing or infections in the lung tissue. If the tumor presses on the spinal cord it may cause leg or arm weakness or paralysis. A tumor in the neck may cause a lump in the neck and/or may cause pressure on nerves, which lead to the drooping of an eyelid.
Neuroblastoma often spreads to other sites such as the lymph nodes, liver, lungs, bone, and bone marrow. If this is the case, your child may have bone pain, a lump on the skin, and/or one eye may look as if it is bruised or bulging outward. Your child may not have any of these signs at all and may only be irritable and appear to be in pain.
How is neuroblastoma diagnosed?
When neuroblastoma is suspected, a thorough medical history will be taken and a thorough physical examination will be performed. In order to determine the stage of the disease, your child will also need to undergo various tests and procedures. The tests may include some or all of the following:
- Blood tests. A complete blood count and blood chemistries test may be ordered.
- Urine test for VMA (vanillymandelic acid) and HVA (homovanillic acid). This test measures the amount of these catecholamines in the urine. Catecholamines are substances that are sometimes produced and secreted by neuroblastoma tumors. Urine will be collected with a collection bag or a urinary catheter if your child is not toilet trained. This test is done before, during, and after treatment to help determine if the tumor is gone or if it is returning.
- Bone marrow aspiration/biopsy. A sample of bone marrow is taken from the hip bone to determine if tumor has spread to the bone marrow.
- X-rays. A chest x-ray and/or skeletal survey may be performed.
- Bone scan. A test where a small amount of radioactive dye is injected by IV followed by a scan of the body to see if the disease has spread to the bones or other tissue.
- MIBG scan. This test is similar to a bone scan. A special dye (MIBG) is given IV and is absorbed only by tumor tissue on the body.
- Ultrasound. To determine the extent of the tumor. The ultrasound test uses high frequency sound waves to look for body structures.
- Computed tomography (CT scan). A test that produces images of the scanned body parts. The chest and abdomen are usually scanned to look at the extent of this type of tumor. Frequently, dye is injected to help the radiologist outline areas of tumor.
- Surgical biopsy. Is often necessary to obtain a small sample of the tumor. The biopsy will be done under general anesthesia. The tumor sample will be examined by a pathologist. A pathologist is a doctor that diagnoses cancer by examining tumor tissue under a microscope and by conducting biology tests on the tissue. It may take several days to receive the results.
A careful diagnosis is essential to determine the best treatment possible. Part of diagnosing neuroblastoma is classifying it into one of the following stages to indicate the extent of the disease:
- Stage I. The tumor is only in the place where it first began to grow and is completely removed during surgery.
- Stage II. The tumor has spread away from its original place, but remains only on one side of the body.
- Stage III. The tumor has spread from its original place to a neighboring area in the opposite side of the body with or without involvement of lymph nodes.
- Stage IV. The tumor has spread from its original place to a distant area such as the bone, bone marrow, liver or lymph nodes.
- Stage IV-S. Same as Stage I or II with bone marrow and/or liver and/or skin involvement, in a child 12 months or age or less.
How is neuroblastoma treated?
For treatment, children with neuroblastoma are assigned to one of three risk categories: low, medium, and high. The risk assignment is based on the tumor's stage, the child's age, and the results of biology tests done on the tumor tissue by the pathologists. Children with higher risk disease have a greater chance of the tumor coming back and therefore need to have more intensive chemotherapy.
Treatment usually includes a combination of chemotherapy, surgery, and for some patients, radiation therapy. Your doctor will explain the specific treatment for your child. The goal for surgery is to completely remove the tumor without damaging vital structures around the tumor. Sometimes chemotherapy is used to shrink the tumor before surgery, allowing for surgery that is less extensive later.
Chemotherapy is given intravenously (into a vein). The goal of drug therapy is to find tumor cells wherever they are, destroy them, and prevent their future growth. Each drug has side effects that will be described specifically to you. The chemotherapy is given through a central venous catheter, which is a thin tube inserted into a large vein. The catheter will be used throughout treatment to give your child IV chemotherapy and take blood samples. This means fewer needle pokes and less pain for your child.
Radiation therapy is given in addition to chemotherapy for children with high-risk neuroblastoma or those with diagnosis and staging where recurrence of the tumor is likely. Throughout the course of therapy and after treatment is completed, various follow-up studies such as blood and urine tests, CT scans and x-rays will be done to closely monitor your child.
Stem cell transplant is another treatment option for children diagnosed with high-risk neuroblastoma. The goal of this treatment is to maximize the dosages of chemotherapeutic agents used against the tumor cells. These higher dosages of chemotherapy also destroy the normal bone marrow cells, prohibiting their recovery. Bone marrow is responsible for the production of immature stem cells that grow into blood cells the body needs including red blood cells, white blood cells, platelets, plasma cells and other important cells. The bone marrow is restored to the child by using his or her own stem cells that are removed and saved before the chemotherapy is given, allowing the return of normal bone marrow function.
What research is currently underway?
Current clinical trials are looking at the role of monoclonal antibodies in the treatment of high-risk neuroblastoma. A monoclonal antibody is a single clone of carefully designed cells produced in a laboratory to attach to specific defects in cancer cells. The antibodies are infused via a central line catheter into the child's blood stream to kill cancer cells or prevent their spread or growth. Monoclonal antibodies mimic the antibodies your body naturally produces as part of your immune system's response to germs, vaccines and other invaders. Together you and your doctor can decide whether any of the monoclonal antibody treatments available may be right for you.
About treatment for neuroblastoma at Children's
Children's cancer and blood disorders program consistently achieves treatment results ranking it as one of the top 10 programs in the U.S. Children's treats the majority of children with cancer and blood disorders in Minnesota and provides patients with access to a variety of clinical trials and the very latest treatment options that may not be available at all centers. Your child's doctor will talk in detail with you about any new treatment that might be a match for your child. Then you decide whether you want to try this option. Through our renowned solid tumors program, patients experience unparalleled family support, a nationally renowned pain and palliative care team, and compassionate, coordinated care.
If you are a family member looking for a Children's hematologist or oncologist or wanting to schedule an appointment, please call our clinic at Children's – Minneapolis at (612) 813-5940.
If you are a health professional looking for consultation or referral information, please call Children's Physician Access at 1-866-755-2121 (toll-free) and ask for the on-call hematologist/oncologist.