Childhood cancer often strikes its youngest victims the hardest, and the death rate for infants may be up to four times higher than previously thought, US researchers said Monday.
The study in the Journal of Clinical Oncology examined deaths within a month of diagnosis, those young lives which usually end before the patients can be enrolled in a clinical trial that might save them.
"During my pediatric residency a teenager came in with leukemia, but had so much cancer when he presented that he had multi-organ failure and died within about 24 hours of coming to our attention, before we could even start treatment," said lead author Adam Green, investigator at the University of Colorado Cancer Center and pediatric oncologist at Children's Hospital Colorado.
"I wanted to find out who these kids are in hopes that as a system we could learn to spot them earlier, when treatment still has a chance of success."
So researchers based their study on a US database known as Surveillance, Epidemiology and End Results (SEER), which showed more than 36,000 cases of pediatric cancer between 1992 and 2011.
Most of the research on childhood cancers comes from clinical trials involving treatments that might save lives.
But Green and colleagues found that the SEER database showed that 6.2 percent of children with acute myeloid leukemia died early, compared with 1.6 percent in clinical trial data.
When researchers looked at early deaths from all kinds of pediatric cancer in the SEER database, which encompasses a broad section of the United States as a whole, they found that early cancer death rates were at least two to three times higher than reported in clinical trial data.
"Most of what we know about outcomes for cancer patients come from clinical trials, which have much more thorough reporting rules than cancer treated outside trials," said Green.
"However, these kids in our study aren't surviving long enough to join clinical trials."
Previous research has shown that treatments for childhood cancer have vastly improved the five-year survival rate.
Today, more than 80 percent of kids diagnosed with cancer survive for five years.
A total of 555 -- or 1.5 percent of the child patients in the SEER database -- died within one month of cancer diagnosis. Those who died so quickly tended to be under age one.
"Babies tend to get aggressive cancers, it's hard to tell when they're getting sick, and some are even born with cancers that have already progressed," said Green.
"These factors combine to make very young age the strongest predictor of early death in our study."
Knowing more about those who die swiftly could lead to improved diagnostics, and better care so that more children can have a chance at survival, he said.
"This is a population that deserves our attention."