A new study has shown that many women who receive chemotherapy for a specific type of breast cancer do not need it. The type of tumour involved, called hormone-receptor-positive, accounts for roughly half of all breast cancers.
Researchers recruited women from across North America, including some receiving treatment at the sa国际传媒聽Cancer Clinic in Vancouver. The results showed that as long as this type of tumour has not advanced to other parts of the body, chemotherapy might not be required.
Thanks to mammography, which detects tumours at an early stage, the vast majority of women diagnosed with breast cancer today do not have advanced tumours. That increases the impact of this new discovery.
In days gone by, 60 per cent of women with this kind of tumour would have been given chemotherapy. In sa国际传媒, that translates into 1,200 newly diagnosed patients each year. But of those 1,200, we now know 840 do not need chemotherapy.
Surgery is still required, but after that, new medications such as Tamoxifen are sufficient to produce a successful outcome. And unlike traditional chemotherapy, which many patients dread, these new medications are easily tolerated.
This breakthrough is the latest application of what is being called personalized medicine.
Women with early-stage breast cancer have their DNA read. The test, which is government funded, shows whether patients have the right type of tumour. (A reminder: We鈥檙e talking about only one type of breast cancer. Other varieties would not benefit from this treatment.)
The new approach might also apply to other forms of cancer. In sa国际传媒, 3,200 men are diagnosed each year with prostate cancer. Chemotherapy isn鈥檛 used here, but DNA testing might show whether the tumour is progressing slowly enough that surgery is not required. That鈥檚 a huge advantage, as serious side-effects sometimes follow prostate surgery.
Colorectal cancer is also a potential target. Last year, 4,000 British Columbians were diagnosed with this disease. It鈥檚 possible DNA testing could reduce the use of chemotherapy in dealing with this type of cancer.
That is the good news. But there is, as always, another side to the story.
DNA testing is expensive. We don鈥檛 know the cost in sa国际传媒 because it鈥檚 considered proprietary information, but in the U.S., the price per patient is $6,000 Cdn.
Last year 13,000 women, sa国际传媒-wide, were diagnosed with hormone-receptor-positive tumours. Using the American price tag, testing would have cost about $80 million.
And that is just the start. Personalized medicine will play a central role in health-care systems of the future. Many ailments are genetically based, such as Alzheimer鈥檚, Type 2 diabetes, Parkinson鈥檚 disease and dozens more.
It will eventually be possible to treat these conditions far more effectively using individualized gene testing. But while costs will probably decline as the procedure becomes more common, there will still be an enormous financial impact.
And that creates a dilemma. Just how much benefit to an individual patient is required to justify the costs involved?
Certainly, if the procedure might be life-saving, that would be sufficient. But what if it merely reduces symptoms somewhat? Or in the case of this new DNA test for breast cancer, it does not create a better cure rate but merely helps patients avoid an unpleasant form of treatment? Where do we draw the line?
Medications for some illnesses can cost $750,000 per patient per year, but these are generally rare ailments. Personalized medicine, if it achieves its full potential, will have a far greater reach.
Financially speaking, this is perhaps the greatest challenge facing our already strained health-care system (though aging is a close second). It鈥檚 a predicament that must be solved.
