There are far fewer child deaths from the most common pediatric eye cancer when surgeons quickly remove the affected eye instead of trying to treat the tumours with chemotherapy, new research shows.
Retinoblastoma is a relatively rare disease that affects about one in every 15,000 children globally.
In Canada, the mortality rate is one per cent, thanks to advanced diagnosis and treatment. Death rates are higher elsewhere in the world.
The new study gives evidence that surgically removing the eye is the best option to prevent the cancer from spreading.
Doctors may mistakenly believe that shrinking the cancerous tumour with drugs can save vision and ease surgery later, researchers say.
Parents often resist enucleation — surgical removal of the eye. While heart-wrenching for families, taking out the eye is most effective, the team discovered.
To reach that conclusion, an international team analyzed 100 eyes removed from retinoblastoma patients at Beijing Tongren Hospital in China from May 2006 to October 2008. They found a startling difference in deaths depending on when an affected eye was removed after diagnosis.
There were no deaths in the patients who had an eye removed promptly. Among the patients who had chemotherapy that delayed the surgical removal of the eye to more than three months after diagnosis, five patients, or nearly 17 per cent, died, the researchers reported in the Journal of Clinical Oncology.
In severe cases, chemotherapy causes a delay that gives the tumour time to grow toward the brain, said the study's principal investigator, Dr. Brenda Gallie, an ophthalmologist at Toronto's Hospital for Sick Children.
"We published it in a major oncology journal so hopefully it will reach the oncologists who need to say, 'Wait a minute, I don't want to treat that child because that eye should come out first. Not that we won't use chemo to save eyes that are less involved," Gallie said in an interview Tuesday.
The researchers suspected that while chemotherapy could give the illusion of shrinking the initial tumour, the true extent of the spread of the disease at a microscopic level was masked. By the time the cancer was detected, it had metastasized to the brain and other areas of the body.
Opthamologists call a severely affected eye that needs to be removed an "E" eye, the highest on a five-point scale of severity.
In Canada, two E eyes are very uncommon. In contrast in Africa, most children come to the attention of doctors when the disease is so advanced that eyes are already pushing out of the head, Gallie said. In China, such cases are usually diagnosed before reaching that stage, she added.
Gallie has devoted her career to treating retinoblastoma, studying the science of how the tumours form and their genetic cause.
"I became dissatisfied with my scientific contributions personally when I realized the quality of care that we can deliver in Canada is available to eight per cent of the children in the world with the disease. Ninety-two per cent have no access to that. So I said I want to do something to take what was already discovered and make it useful," she said of her drive to get the information out to parents and physicians.
The rarity makes it difficult to compare treatment options like surgery versus chemotherapy except in countries like China that have a large number of cases.
Gallie argues since retinablastoma affects so few children, there's an opportunity to provide all of them with access to high-quality care.
Jeff Healey's son tumour-free
The argument rings true for Cristie Healey. Her husband, jazz musician Jeff Healey, died in 2008 of cancer at the age of 41. Healey had his eyes removed at age one as a result of retinoblastoma, a condition that was passed on to their son Derek.
Derek, 5, has now been tumour-free for four years, and does not need to wear glasses, his mother said, thanks to proactive laser and freezing treatments. Derek was diagnosed with a dozen tumours in both eyes by 18 months.
"There was that feeling of devastation," Cristie recalled of Derek's initial diagnosis and treatments.
"As time went on, I realized as a parent you do things for your children that they're not happy about. But you're doing them for your children because you love them and you know the outcome is what's important. Once I came to that realization, then I adapted that way of thinking."
While Cristie never had to face the decision to remove Derek's eyes as Jeff's parents did to save his life, Cristie did have to weigh chemotherapy for their son. Fortunately, Derek's eyes have always responded to the proactive treatments.
Cristie calls Gallie's research "phenomenal" because it shows parents and doctors can take steps to help children live happy, healthy and productive lives.