Survivors of childhood cancers at increased risk of other cancers later in life
Survivors of childhood cancers are four times more likely than the general population to develop a new cancer according to a recent study by cancer research scientists.
The researchers followed the health of over 18,000 childhood cancer survivors for an average of 25 years. They found that in middle age, survivors of childhood cancers were at greater risk of developing certain types of new cancers - especially of the digestive or genitourinary systems, such as bowel cancers and kidney cancers. Among the survivors of childhood cancers there were 837 new cancers, almost four times the 216 that would be expected in the same number of people in the general population.
The recent study indicated that 5% of survivors of childhood cancers had developed a new cancer by age 38, as compared with age 54 years in the general population.
Dr Raoul Reulen (of Birmingham University, England), author of the study said:
" We know that survivors of childhood cancer are at increased risk of developing new cancers, but we didn't know what the long term risks were as they reached middle age. By knowing the cancers that survivors are most at risk of we can focus attempts to prevent or pick up cancers earlier hopefully helping them to be treated successfully."
It is interesting to read opinions that "most of the increased risk of developing further cancers can be attributed to the treatments used for the original cancer" (from Cancer Research UK Press Release, 4 Jun 2011). Scientists are currently investigating ways to minimise these effects in the future. Nevertheless, researchers considering recent statistics have reported that cancer survivors who were treated using radiotherapy to the abdomen and pelvis 20 to 30 years ago were three times more likely to develop a new cancer of the digestive system. Given that the risk for developing bowel cancer among this group was similar to those who have a strong family history of the disease the researchers have even suggested that such patients might be be offered colonoscopy screening to detect possible bowel cancers earlier.
Dr Reulen added:
" The increased risk of developing new cancers in survivors is still relatively low overall, but we encourage survivors to take part in the existing screening programmes for bowel, cervical and breast cancer."
The recent study also showed a changing pattern in the cancers being seen amongst survivors as they got older. Digestive and genitourinary cancers are relatively rare among survivors younger than 20 years, but they become more common over time. Overall, five year survival rates for childhood cancer patients has improved over the last 40 years. Today almost 80% of patients survive childhood cancers (for at least 5 years) so there is an increasing need to reduce the late side-effects of some of the treatments they have received.
Dr Lesley Walker, director of cancer information at Cancer Research UK, said:
" Treatments for childhood cancers have undergone major changes and are continually improving leading to the greatly improved survival rates we now see. This important work will help identify earlier those childhood cancer survivors who are at greater risk of developing new cancers.
_The current treatments used today, such as radiotherapy, have been refined to focus on the tumour so are likely to result in fewer cancers in the surrounding areas. Cancer Research UK is continually looking at new treatments that will help more children survive cancer and reduce the long term effects that curative treatments can bring."
Reference to Paper:
Reulen, R.C. et al Long-term risks of subsequent primary neoplasms among survivors of childhood cancer, JAMA (2011).
http://www.cancerresearchuk.org (Press Release)