As anyone who’s fond (or not so fond) of clothes-shopping will know, the idea that “one size fits all” is a myth. And the same is true of cancer treatment.
Fundamentally, cancer is due to faulty genes – this is usually a combination of genetic variations inherited from our parents, topped with the random mistakes that happen during a lifetime’s wear and tear. But the distinct signature of gene faults in an individual tumour also affects how the disease responds to treatment.
Increasingly, scientists and doctors are working together to make “personalised medicine” a reality, as it becomes clear that all cancers are not the same. The idea is that a patient will get a treatment tailored to the genetic makeup of their cancer, which is more likely to work than a “one size fits all” standard treatment.
For example, in the case of breast cancer, the disease can be broken down into several different sub-types, depending on the genes that are active within a tumour. And each subtype may require a slightly different treatment approach.
Cancer Research UK scientists from Edinburgh have just announced an important step forward in this area, discovering that a genetic test (already used in breast cancer diagnosis) can predict whether an individual patient will benefit from certain chemotherapy drugs or not. And we could see it become standard clinical practice within a couple of years.
The story starts with Professor John Bartlett and his team, who were searching for genetic ‘markers’ that could help to identify women with breast cancer who would benefit from anthracycline drugs, such as the commonly used epirubicin.
While these drugs are very effective in some women, they can cause unpleasant side effects, and this has limited its use. So identifying people who won’t get any benefit from it would be a good thing.
A NEAT finding
The scientists trawled through tumour samples taken from more than 2,500 women who had been taking part in clinical trials of breast cancer chemotherapy, including the UK’s NEAT (National Epirubicin Adjuvant Trial).
After painstaking analysis, they found that if a woman’s tumour had extra copies (duplication) of a certain region of DNA found on chromosome 17, they were likely to respond to the treatment. But this wasn’t the case for women with the normal complement of DNA.
Duplication of chromosome 17 is already known to be involved in breast cancer – it harbours HER2, the gene that makes the molecule targeted by Herceptin. And there’s an effective test to look for duplications of the chromosome, which is routinely used by doctors to find out if a woman will benefit from Herceptin treatment.
What does it mean?
The great thing about this finding, presented at the San Antonio Breast Cancer Symposium, is that both the duplication test and the drug are already available here in the UK for doctors to use.
The team are still waiting for the results of one final clinical trial to confirm the accuracy of the test. But if all goes well, we should see this becoming clinical practice, and directly benefitting patients, within a year or two.
Listen to an interview with Professor Bartlett, talking about this research.
Kat
Comments
Kat February 6, 2009
Carol and Beth,
You’re right that tamoxifen and other hormone treatments aren’t suitable for long-term follow-up treatment for women with oestrogen-receptor-negative (ER-negative) breast cancer. This is because these types of cancers don’t respond to oestrogen, so treatments that block oestrogen production or action (like tamoxifen) have no effect.
I’ve been doing some digging about for information about research into long-term follow-up treatment for ER-negative breast cancer, but there isn’t too much to report. Most of the work in this area revolves around chemotherapy in the first year or two after diagnosis.
Last year, researchers in New Zealand published research in the British Journal of Cancer suggesting that combining tamoxifen with a drug called epigallocatechin gallate (EGCG) could prevent the growth of ER-negative breast cancer cells implanted into mice. But this combination still needs a lot more investigating, not to mention clinical trials, before we know for sure if it would be helpful for women with ER-negative breast cancer. (PubMed reference: http://www.ncbi.nlm.nih.gov/pubmed/18797454)
It’s likely that answers to this problem will come from research into fundamental cancer biology, and the genes that control cancer cells. Cancer Research UK is funding a significant amount of this work, looking at “nuts and bolts” of cancer cells and trying to understand how and why they grow. At the moment, we are still identifying the genes and molecules involved, but we hope that in years to come we will be able to turn this knowledge into new treatments – just as research from previous decades has led to the development of improved hormone treatments, and drugs like Herceptin.
If you’ve got any questions about cancer and its treatment, you may find it useful to contact our Cancer information nurses: http://cancerhelp.cancerresearchuk.org/utilities/contact-us/ And you can talk to other people who have been through cancer on our CancerChat forum: http://www.cancerchat.org.uk/
I hope you’ve found this information helpful,
Kat
Henry Scowcroft February 5, 2009
Peter – we discussed the issue of antiperspirants, aluminium and breast cancer in this post:
http://news.cancerresearchuk.org/2007/08/31/breast-cancer-deodorants-or-the-no-links-effect/
sheila chambers February 5, 2009
i have secondary breast cancer in the bones. I had epirubicin in my first treatment 5 years ago, and tamoxifen. I have had a test for herseptin, but I am not receptive for that.
No breast cancer known in my parents, although father died of cancer.
If I had the gene tests would it of any help for my children in any way.
beth smith February 5, 2009
Like Carol Turansky I also look for follow ups but 8 years after treatment I am still rejoicing as I am sure she is. My oncologist took blood samples for a trial to pinpoint treatment so perhaps I am part of the good news discovery.
Carol Turansky February 5, 2009
Five years after surgery/chemo/radio for breast cancer I continue to search the internet for news of preventative/follow-up treatment for those, like me, who are oestrogen receptor negative ie. once we’ve had our initial treatment that’s it: no tamoxifen etc., and it’s all ‘in the lap of the gods.’
I wonder if there is in fact anything in the pipeline please?
Peter Stockwell-Jones February 5, 2009
Can you confirm that the aluminium salts (mainly Aluminium Chlorohydrate, I beleive) used in the vast majority of anti-perspirants, may be a contributing factor to male & female breast cancer?
Lesley Findlay May 4, 2009
I have just finnished chemotherapy for the 2nd time for the re-occurence of breast cancer which I have been fighting since a mastectomy in 1996.I had 10yrs cancer free courtesey of tamoxifen.In 2006 it came back and since then I have had arimidex,and letrozole.On my recent visit to the consultant she has now put me back onto tamoxifen to see how I get on.I’m afraid the position I find myself in is does any of these consultants really know how to treat to benefit the patient or just another statistic which can be disposed of.Any drug found that can do away with chemotherapy must be a plus.