Modernizing the fight against kidney cancer
Figlin, the Arthur and Rosalie Kaplan Professor of Medical Oncology at City of Hope, specializes in kidney cancer — a disease notoriously difficult to treat and even harder to cure. Once, when patients came to him with advanced cancers, he and his colleagues had few standard, successful options to offer them.
Now times have changed — a testimony to dramatic leaps in medical science made since the dawning of the 21st century.
“We’ve now found three new drugs since late 2005 that show promise against kidney cancer — a disease that has desperately needed better treatments,” said Figlin, associate director of clinical research at City of Hope’s Comprehensive Cancer Center. “We’re finally making progress against it.” He ticks them off one by one with his fingers. Sunitinib. Sorafenib. Temsirolimus. And bevacizumab (also known as Avastin) shows promise, too.
Long sympathetic to patients’ frustrations, Figlin now sees hope. “We’re still working on more options, different regimens, new therapies based on our understanding of how kidney cancer works,” he said.
As Figlin explained, when patients are diagnosed with early stage kidney cancer that is confined to the kidney, surgery is the best option. More than 90 percent of these patients stay free of the cancer after treatment.
photo COURTESY OF UCLARobert Figlin
But the odds worsen dramatically as kidney cancer grows and spreads. Traditional, cell-killing chemotherapies and radiation therapy do little against advanced kidney cancer. So researchers turned to immunotherapies to counter the disease. These therapies push the body’s own immune system to fight cancer.
One of these therapies is interleukin-2, a protein that activates the immune system. Research showed that interleukin-2 shrinks metastatic kidney cancer tumors in 10 to 20 percent of patients, with some remissions longlasting, so it has become a treatment option. But the treatment comes at a price: It can cause serious side effects.
Fortunately, trials of a flurry of new drugs have brought better results and fewer side effects.
Figlin was senior author on a study in the Jan. 11 issue of the New England Journal of Medicine showing that the drug sunitinib worked better than the immunotherapy drug interferon alfa — actually doubling the time until patients’ cancers began to progress again after treatment. The multicenter trial also showed patients on sunitinib had a better quality of life than those on interferon alfa.
Another large study involving Figlin in the same journal only four months later showed that the drug temsirolimus helped patients live nearly twice as long after treatment started than did interferon alfa.
Both sunitinib and fellow drug sorafenib, which were approved by the Food and Drug Administration for kidney cancer, starve kidney cancer tumors by interfering with the cancer’s ability to create new blood vessels to feed itself. Temsirolimus acts similarly, but also scrambles signaling inside cells, suppressing proteins that help cancer cells develop and mature.
“When we investigate the biology of these tumors and do the hard work to understand what fuels them, we can attack them in a smarter, more strategic way,” Figlin said. His next step: a clinical trial to test a new drug, perifosine, for those with kidney cancer resistant to sunitinib and similar therapies. He also is exploring new immunotherapies with other City of Hope colleagues.
“The other exciting thing about these provocative therapies is that they often start out in clinical trials for uncommon diseases such as kidney cancers,” Figlin said, “but then they move on to other cancers and benefit many other patients.”