They are four words that no parent ever wants to hear: "Your child has cancer."

But new research shows that thanks to a gentler approach to treatments for childhood cancer, more children are surviving the disease than ever before, and with fewer lifelong side effects.

According to a study by St. Jude Children's Research Hospital, more than 80 percent of children survive after being diagnosed with cancer. This increased survival rate (up from only 30 percent 50 years ago) is despite — or possibly because of — a push to make cancer treatments gentler for children.

Radiation and chemotherapy are the go-to treatments for most types of childhood cancer. There is no denying that they work, but the cure sometimes comes at a price. Both treatments are associated with long-term complications such as secondary cancers or heart and organ failure that can take the life of a child even years after she goes into remission.

So a push began in the 1990s to give smaller, more targeted doses of radiation and to change the drugs administered for chemo when treating kids with cancer. But some worried that these changes might reduce the effectiveness of the treatments. According to the new study, those fears are unfounded. 

The St. Jude's research tracked more than 34,000 children who had been diagnosed with cancer since the 1990s over several decades of treatment and remission. The study found that survival rates continued to increase even when gentler treatment methods were used. And there were fewer cases of secondary cancers or heart or organ problems that emerged in the children when these gentler methods were used. 

"The field needs good news and this study gives it," said Dr. Greg Armstrong the lead researcher for the Childhood Cancer Survivor Study which was funded by the National Cancer Institute.  

Related on MNN: