Personal therapy for cancer care
SAN DIEGO (AP) — Doctors were just guessing a decade ago when they gave Alison Cairnes’ husband a new drug they hoped would shrink his lung tumours.
Now she takes it, but the choice was no guesswork. Sophisticated gene tests suggested it would fight her gastric cancer, and they were right.
Cancer patients increasingly are having their care guided by gene tumour boards, a new version of the hospital panels that traditionally decided whether surgery, radiation or chemotherapy would be best. These experts study the patient’s cancer genes and match treatments to mutations that seem to drive the disease.
“We dissect the patient’s tumour with what I call the molecular microscope,” said Dr. Razelle Kurzrock, who started a board at the University of California, San Diego.
It’s the kind of care many experts say we should aim for — precision medicine, the right drug for the right person at the right time, guided by genes. There are success stories, but also some failures and many questions:
Will gene-guided care improve survival? Does it save money or cost more? What kind of gene testing is best, and who should get it?
“I think every patient needs it,” especially if cancer is advanced, said Kurzrock, who consults for some gene-medicine companies. “Most people don’t agree with me — yet. In five years, it may be malpractice not to do genomics.”
If you have a cancer that might be susceptible to a gene-targeting drug, you may be tested for mutations in that gene, such as HER2 for breast cancer. Some breast or prostate cancer patients also might get a multi-gene test to gauge how aggressive treatment should be.
Then most patients get usual guideline-based treatments. If there’s no clear choice, or if the disease has spread or comes back, doctors may suggest tumour profiling — comprehensive tests to see what mutations dominate.
That’s traditionally been done from a tissue sample, but newer tests that detect tumour DNA in blood are making profiling more common. The tests cost about $6,000 and many insurers consider them experimental and won’t pay.
Gene tumour boards analyze what the results suggest about treatment. They focus on oddball cases like a breast cancer mutation in a colon cancer patient, or cancers that have widely spread and are genetically complex. The only options may be experimental drugs or “off-label” treatments — medicines approved for different situations.
But as tumour profiling grows, it’s revealing how genetically diverse many tumours are, and that oddball cases are not so rare, said Dr. John Marshall, head of the Georgetown Lombardi Comprehensive Cancer Center.
“There is a little bit of faith” that testing will show the right treatment, but it’s not a sure thing, said Dr. Lee Schwartzberg, who heads the West Cancer Center in Memphis.