Children who survive cancer are at risk of having learning difficulties and poor achievement in school, finds new research from B.C. cancer experts.

The study, funded by the Canadian Cancer Society and published in the journal Cancer, finds that cancer survivors often complete less education and are more likely to need special education services.

The study looked at almost 800 childhood cancer survivors from the British Columbia Cancer Registry who had survived for more than five years after diagnosis and who attended B.C. schools from 1995 to 2004. Researchers led by Mary McBride, a researcher at the B.C. Cancer Agency, compared them with a randomly selected group of about 8,300 B.C. school children.

They found that while some cancer survivors had no lingering after-effects, those who had been diagnosed with central nervous system tumours, such as brain cancer, appeared to have troubles with math and reading.

Survivors were also significantly more likely than healthy children to receive special education -- 32.5 per cent vs. 14.1 per cent. And the research found that girls and those who had received radiation (particularly radiation of their brains) were at increased risk for poor educational outcomes.

Brandon Radnai is a cancer survivor who is still living with the effects, nine years after he was treated for Stage 4 medulloblastoma, a brain tumour that had spread down his spine.

He underwent surgery, aggressive chemotherapy and 41 radiation treatments. Despite his poor initial outlook, Brandon survived. But he lives with ongoing health challenges.

Brandon recently had surgery on his back to help with pain and improve mobility. He has trouble keeping weight on and needs food supplements and growth hormones. And while he wears hearing aids because of the damage to his hearing, he is increasingly becoming deaf.

Barbara Kaminsky, the CEO Canadian Cancer Society BC and Yukon, says that while advances in treatment have increased the survival rate of children diagnosed with cancer to over 80 per cent, many of these children never fully recover.

"We've celebrated our cancer survival rates, but these positive outcomes have come at a price, because for some of these cancer survivors, they don't have the same quality of life as others would have," Kaminsky told CTV.ca.

"So on the one hand, while young people tend to respond very well to treatments, on the other, it leaves them with after-effects."

The "adverse late effects" that childhood cancer survivors can face may be related to the disease itself or the aggressive treatments or both. Cancer treatment tends to be harsh, particularly on a young body that is still developing, says Kaminsky.

"A lot of people who have been critical of our traditional cancer therapy of radiation, surgery and chemotherapy describe it as 'burn, cut and poison.' And although that sounds harsh, there is a degree of truth to that.

"So what we need to do, obviously, is fund better research so that we can have positive outcomes in terms of survival but also have the patients who survive thrive as healthy human beings."

There has been plenty of anecdotal knowledge over the years that childhood cancer survivors can have intellectual deficits. But with more survivors returning to the education system, the full picture is only now emerging.

"It's only been in recent times, we are getting good quality data," says Kaminsky. "Often, when people are no longer receiving treatment, they leave the system, so we haven't had good data on their functioning.

"This type of research that follows people years after their treatment is very important."

This study is believed to be the first population-based research to use standardized measures to examine educational late effects of survivors of all childhood cancers.

The findings have important implications for survivors, their families and educators, who need to be aware of potential educational difficulties, says the Canadian Cancer Society BC and Yukon.

Regular monitoring of progress within the school system is essential to proving appropriate management of this group.