Neuroblastoma is a form of cancer that starts in certain types of very primitive developing nerve cells found in an embryo or fetus. (The term neuro indicates "nerves," while blastoma refers to a cancer that affects immature or developing cells). This type of cancer occurs in infants and young children. It is rarely found in children older than 10 years.
How Neuroblastomas Grow:
Neuroblastomas are cancers that start in early nerve cells of the sympathetic nervous system, so they can be found anywhere along this system.
A little more than 1 out of 3 neuroblastomas start in the adrenal glands. About 1 out of 3 begins in the sympathetic nerve ganglia of the abdomen. The rest start in sympathetic ganglia of the chest or neck or in the pelvis.
In rare cases, a neuroblastoma may have spread so widely by the time it is found that doctors can't tell exactly where it started.
Neuroblastomas can behave strangely. Sometimes the cells die without any cause and the tumor disappears. Tumor disappearance is much more common in very young infants than in older children. Another behavior that is unusual for childhood tumors is that the cells sometimes mature spontaneously into normal ganglion cells and stop dividing. This causes the tumor to become a ganglioneuroma.
Other Autonomic Nervous System Tumor:
Ganglioneuroblastoma is a tumor that has both malignant and benign parts. It contains neuroblasts (immature nerve cells) that can grow and spread abnormally, as well as areas of more mature tissue that are similar to ganglioneuroma.
Signs or Symptoms Caused by Hormones from the Tumor:
Neuroblastoma is one of the few cancers in children that release hormones that can cause strange changes in the body. These changes are called paraneoplastic syndromes.
Symptoms of paraneoplastic syndromes can include:
- fever (in about 1 out of 4 children)
- constant diarrhea
- high blood pressure (causing irritability)
- rapid heartbeat
- reddening (flushing) of the skin
- sweating
Low-risk group: Low-risk children have a 5-year survival rate of around 90% to 95%.
Intermediate-risk group: In intermediate-risk children, the 5-year survival rate is around 85% to 90%.
High-risk group: The 5-year survival rate in high-risk children is around 30%.
