Late Effects

On average approximately 10,400 North American children (between birth and 14 years of age) develop childhood cancer each year.

More than 80% of these children will be long term survivors who have been cured of their cancer.  This was very different 20 – 30 years ago, when the majority of children did not survive their illness.

In general, cure rates have been improved by using:

  • Multiple treatments:
    • Chemotherapy
    • Surgery
    • Radiation therapy
  • Therapy intensification (using higher total doses of chemotherapy over a shorter period of time)
  • Improved supportive care

Though this approach has greatly improved the chance of curing the cancer, it has become obvious over the past 10 to 20 years that survivors of childhood cancer are at risk for many significant long-term health risks or “late effects” as a result of this treatment.

Late effects are generally classified as side effects that occur more than 5 years after diagnosis – though there is debate about this definition.  For example, acute myeloid leukemia (AML) related to treatment with a chemotherapy drug called Etoposide often occurs within 3 years of therapy and is considered a treatment related side effect.

It was previously estimated that two thirds of childhood cancer survivors have at least one chronic health problem related to their previous cancer therapy and up to one third of these late effects would be major, serious or life threatening. However, a recent study from the St. Jude Children’s Research Hospital published in JAMA showed that these health problems are more common. Here is the article:

Clinical Ascertainment of Health Outcomes among Adults Treated for Childhood Cancer

They recalled and assessed just over 1700 adult childhood cancer survivors and found that at age 45 years, there was a:

  • 95.5% cumulative prevalence of any chronic health condition
  • 80.5% cumulative prevalence for a serious/disabling or life-threatening chronic condition

This study also showed that the risk of long-term health problems in cancer survivors increases with age and time from therapy.

Late effects can cause serious problems both physical and psychological which affect childhood cancer survivors for the rest of their lives.  These psychological problems after treatment for childhood cancer cannot be underestimated and we have been involved in research into this problem:

Parents' perspectives

At present there is no comprehensive clinical program in British Columbia to address the needs of childhood cancer survivors and we are advocating for change.


Information about late effects

There are some great on line resources about these long-term health problems together with information on screening and prevention programs.

The Children’s Oncology Group website is well set out and gives clear information about late effects:

Children's Oncology Group website



The National Cancer Institute has an excellent late effects resource:

National Cancer Institute