Childhood cancer survivors face lifelong cancer risk

Washington, May 27 (ANI): People who have been treated for cancer in childhood have a persistent and high risk for a second primary cancer throughout their lives, according to a new study.

In earlier studies, scientists said that second primary cancer risk after treatment in childhood is higher than that in the general population.

However, follow-up was restricted to a few decades and the incidence in long-term survivors was rarely investigated.

The latest study-led by Dr. Jorgen H. Olsen of the Institute of Cancer Epidemiology, Danish Cancer Society-offers data for incidence of second cancers among childhood cancer patients in the Nordic countries over a full age range, from birth to age 79.

For the study, the researchers analysed a cohort of 47,697 people who were diagnosed with cancer prior to the age of 20, from 1943 to 2005.

Members of the cohort were followed for subsequent primary cancers listed in registries, and the age-specific risk pattern of the survivors was compared with that of the national populations using country and sex standardized incidence ratios (SIRs).

And it was found that the observed incidence rate of new primary cancers was higher than the expected rates, and the relative risk of second primary cancers was statistically significantly increased in all age groups.

They observed a total of 1,180 second primary cancers in 1,088 persons, which yielded a SIR of 3.3, with the brain as the most common site.

Also, the researchers found that the relative risk for second primary cancers in male survivors was statistically significantly higher than in female survivors.

"This study quantified long-term temporal patterns of increased risk of cancer at specific sites in survivors of childhood cancer. The results may be useful in the screening and care of these individuals," wrote the authors.

The study has been published in the latest online issue of the Journal of the National Cancer Institute. (ANI)