Childhood cancers are rare, making up less than 1 percent of all cancers. However, it’s the second leading cause of death in children, behind accidents.

Childhood cancer affects not just the child, but also his or her whole family. When cancer strikes a kid, it’s different than adult cancers in some ways.

Here are five things to know about childhood cancer.

1. Leukemias are the most common type of childhood cancer

The types of cancer most often seen in adults are rare in kids. Leukemia, a cancer of the bone marrow or blood, is the most common form of childhood cancer, accounting for about 30 percent of childhood cancers.

Other types of cancer include brain and central nervous system cancers, neuroblastoma that begins in nerve cells, nephroblastoma that begins in one or both kidneys, lymphoma that affects the lymph nodes, as well as cancers that affect the muscles, eyes and bones.

2. Cancer causes and risks are sometimes unknown

While adults can sometimes curb their diets, stop smoking and refrain from drinking alcohol to prevent some types of cancers, childhood cancers aren’t often caused by lifestyle factors. Many times the cause of a childhood cancer isn’t known.

“There’s evidence that some childhood cancers are caused by genetic mutations or changes in DNA that happen very early in life,” said Michal A. Miller, M.D., a pediatric oncologist at Geisinger Health System.

3. Treatment is different in children than in adults

Just like cancer in adults, cancer in children is treated based on the form and the severity. Treatments typically include chemotherapy, surgery, radiation therapy, immunotherapy and stem cell therapy.

Children usually recover faster than adults, so they may be able to endure higher doses of chemotherapy. However, because children are growing and developing quickly, their bodies may react differently to some medicines.

4. Children with cancer are often treated in specialized centers

The types of cancer and treatments are different in children than in adults. Because of this, many children are treated in specialized children’s cancer centers — a department, or even a whole hospital, devoted to treating kids with cancer.

Children’s cancer centers usually treat patients up to 20 years old, and medical professionals provide specialized care just for kids. Just like treatment for adults, kids treated in cancer centers can take part in clinical trials for types of treatment.

5. Survival rates are increasing

While the incidence of childhood cancer has risen slightly over the past several decades, advances in science and treatment mean that survival rates are also increasing. The five-year survival rate for children with cancer now averages over 80 percent, meaning that over 80 percent of kids with cancer live at least five years after being diagnosed.