“What is my child’s prognosis?” This seemingly simple but critical question is often among the first that parents will ask their child’s oncologist after hearing that their child has been diagnosed with cancer.
Yet, while the question may be simple, answering it can be extremely complicated. In general terms, oncologists can provide statistics relating to 5-year survival rates for many different types of brain tumours in children.
These general statistics, however, cannot predict an outcome for any one child. Each child’s individual prognosis will depend on the unique circumstances of their tumor and its response to treatment.
What is a 5-year survival rate and why doesn’t it tell the whole story?
The 5-year survival rate refers to the percentage of children who live at least five years after they have been diagnosed with a brain tumour. As a simple statistic, it can provide some basic information about our ability to treat many different types of brain tumors.
However, as with all “simple statistics”, it has three significant limitations:
- It only takes into account children who were treated at least five years ago. It does not take into account significant improvements in today’s treatment options.
- It can indicate prognosis for a particular class of brain tumors, but does not show differences in prognosis rates for specific tumor types.
- It does not account for each child’s unique diagnosis and key prognosis factors so, as noted above, it cannot predict an outcome for any one child.
As noted above, while five-year survival rates can be useful in general terms, each child’s prognosis will depend heavily on a unique assessment of her or her prognosis factors. These factors will impact the treatment approach and help determine your child’s potential for long-term survivorship.
Key Prognosis Factors for Childhood Brain Tumors Include:
- The type of tumour
- The grade of the tumour, or how quickly it is likely to grow
- The size of the tumour
- The location of the tumour
- Whether the tumour can be removed completely with surgery (if at all)
- Whether the tumorous cells have particular gene mutations
- Whether the tumour has spread to other parts of the brain or spinal cord via the cerebrospinal fluid
- Whether tumorous cells have spread beyond the central nervous system
The child’s age
- The child’s functional abilities as impacted by the brain tumour
Unlike many other forms of cancer, brain tumours rarely spread to areas of the body outside the central nervous system. Instead, brain tumours can be life-threatening because of the damage they can inflict on the delicate and highly critical tissues of the brain and spinal cord.
For this reason, doctors do not use two prognosis factors commonly used when discussing other types of childhood cancers: benign v. malignant and “staging”.
Five-Year Survival Rates for Common Types of Brain Tumors in Children
Based on information from the Central Brain Tumor Registry of the United States (covering children treated between 1995 and 2010), we can provide five-year survival rates for some of the most common types of brain tumors diagnosed in children.
As noted above, however, it is important to remember that these statistics do not accurately represent the chances of long-term survival for any one specific child.
- Philocytic astrocytoma: 95%
- Oligodendroglioma: 90% – 95%
- Fibrillary (diffuse) astrocytoma: 80% – 85%
- Ependymoma (including anaplastic ependymoma: 75%
- PNETs (including medullablastoma and pineoblastoma): 60% – 65%
- Anaplastic astrocytoma: 30%
- Glioblastoma: 20%
SOURCE: American Childhood Cancer Organization (ACCO)