草莓影视

A risk factor is anything that increases the chances of getting a disease such as cancer. Different types of cancer have different risk factors.

Lifestyle-related risk factors such as body weight, physical activity, diet, and the use of tobacco and alcohol play a major role in many adult cancers. But these factors usually take many years to influence cancer risk, and they are not thought to play much of a role in childhood cancers, including neuroblastomas.

No environmental factors (such as being exposed to chemicals or radiation during the mother’s pregnancy or in early childhood) are known to increase the chance of getting neuroblastoma.

Age

Neuroblastoma is most common in infants and very young children. It is very rare in people over the age of 10 years.

Heredity

Most neuroblastomas do not seem to run in families. But in about 1% to 2% of cases, children with neuroblastoma have a family history of it.

In children with this familial form of neuroblastoma (those with an inherited tendency to develop this cancer), the average age at diagnosis is younger than the age for sporadic (not inherited) cases. Children with familial neuroblastoma sometimes develop more than one of these cancers, often in different organs (for example, in both adrenal glands or in more than one sympathetic ganglion).

It’s important to distinguish neuroblastomas that start in more than one organ from neuroblastomas that start in one organ and then spread to others (metastatic neuroblastomas), because tumors that develop in several places at once are likely to be familial. This might mean that family members should consider genetic counseling and testing (see Genetic Testing: What You Need to Know).

Having birth defects (congenital anomalies)

Some studies have shown that children with certain birth defects might have an increased risk of developing neuroblastoma. Some of the link between birth defects and neuroblastoma might be related to changes in genes that happen during fetal development.

Genes are instructions in each of our body's cells that tell them what to do. The development of a fetus, which happens in a mother's womb, is controlled by genes that tell the cells how to grow and divide. If cell growth and development doesn't happen normally in the fetus, it can lead to a birth defect. Changes in genes during fetal development might also increase the risk of some kinds of childhood cancers, like neuroblastoma. For more about genes and causes of neuroblastoma, see What Causes Neuroblastoma?