Potentially Harmful Cancer Drug Removed from Rare Kidney Cancer Treatments

Doxorubicin can be safely omitted in treatments for Wilms' tumor patients deemed least likely to relapse.

A trial by Cancer Research UK has shown that doxorubicin can be safely omitted from treatments for patients with Wilms' tumor.

Wilms' tumor is an extremely rare kidney cancer, affecting young children, most under seven years of age. While doxorubicin is extremely effective in treating cancer, it also comes with the slight risk of future heart problems. A team at Cancer Research UK, headed by Professor Kathy Pritchard-Jones, has shown that this drug can be safely omitted in treatments for those least likely to relapse.

Professor Pam Kearns, professor of pediatric oncology at the University of Birmingham and Cancer Research UK's senior clinical advisor, said, "This is a very important trial that has changed clinical practice for this type of Wilms' tumor. Around 9 in 10 children with the disease survive with current treatments, so it is difficult to consider reducing treatment, but minimising the side effects that occur later in life is crucial."

In a 10 year study from 2001-2011 across 26 European countries, 583 children with Wilms' tumor stage II and III were treated, one group with doxorubicin, and one without. In the group of patients treated with the drug, the survival rate for 5 years or more was 96.5%. In the group without, survival was 95.8%. This shows that while the survival rate was slightly less without doxorubicin, it was only a small amount of patients with Wilms' tumor. Only those with the most aggressive forms of the cancer need the drug in their treatment plans.

Before this experiment, 50% of patients were treated with doxorubicin; now, it can be decreased to 25%. There were slightly more relapses in patients treated without doxorubicin, but they could also be re-treated successfully.

"Thanks to the results of this trial fewer children with this disease will have to have treatment that could cause them lifelong side effects without much benefit," Pritchard-Jones said. "It's taken researchers in 26 countries nearly 10 years to gather the data to support this theory, and none of this would have been possible without the 583 children who took part in the trial and the families that supported them."

The team is now looking to start a trial to isolate the genetic markers in tumor samples for those patients more likely to relapse, so that they can be treated appropriately. They are also looking to find better treatments for children through their Cancer Research UK Kids & Teams program.

This study was published in The Lancet.