Neuroblastoma starts in young nerve cells, called neuroblasts. Normally these cells develop into the nerves that control your child’s automatic functions, such as the heart beat and blood pressure, and the way your child’s body reacts to stress. This part of the nervous system is called the sympathetic nervous system. In neuroblastoma, the neuroblasts never mature. Instead, they divide and grow into tumors.
Typically neuroblastoma tumors develop in the nerves of the adrenal glands, which are located on top of the kidneys and release hormones. But these tumors can begin anywhere in the body. The chest, neck, pelvis, and spinal cord are other common sites.
Most children with neuroblastoma develop the disease before they turn five years of age. Many are between one-and-a-half and two years old. In some children the disease starts before birth. In these cases, as in most cases of neuroblastoma, parents and doctors usually don’t know the disease is there until tumors grow large enough to be felt.
As neuroblastoma advances, it can metastasize, or spread, to other areas of the body. It usually spreads to the lymph nodes (part of the immune system), bones, bone marrow (where blood cells are made), liver, or skin. For most children, the neuroblastoma has spread to at least one of these areas by the time the disease is diagnosed.
The symptoms of neuroblastoma vary depending on where the tumors occur. They may cause a lump which may press on nerves causing pain or weakness. Tumors in the abdomen may push out the abdomen or cause constipation. Anemia (not enough oxygen-carrying red blood cells) may develop if tumors affect the bone marrow. This can cause fatigue. Tumors around the eyes may cause bulging or dark circles. Some children have symptoms caused by problems with the sympathetic nervous system. These may include fast heart beat, high blood pressure, sweating, diarrhea, and flushed skin.
The symptoms listed here can also be caused by other non-cancerous conditions, so it’s important to see a doctor if your child has symptoms that concern you.