After she was diagnosed with breast cancer, Terry Smith kept working — and except for two weeks of sick leave she stayed in relatively good health. One reason the Ottawa woman did so well, despite surgery and radiation treatments, is that she was able to avoid chemotherapy and its side-effects.
“It was wonderful,” she said. “It would have really affected everything, including my health and my job.”
Her story is becoming more common as new research and diagnostic tools improve doctors’ understanding of what works and what doesn’t when it comes to treating cancer. Often that means patients who would have had chemotherapy in the past can now avoid it.
Is this the beginning of the end of chemotherapy? Oncologists say there will always be a role for the treatment, but for many cancer patients, the answer is yes.
The ability to get the same outcomes with less chemotherapy is the biggest recent development in breast cancer treatment, says medical oncologist Dr. Mark Clemons, a clinical investigator of cancer therapeutics at The Ottawa Hospital Research Institute. The trend is being cheered by doctors and patients.
“The vast majority of women, when they see they are going to get minimal benefit from chemo, say, ‘No thanks,’ and I don’t blame them at all,” he said. “Giving chemotherapy is terrible.”
While so-called personalized medicine is still in the early stages, some treatment can be tailored to individual patients rather than being a one-size-fits-all model that, for decades, relied heavily on chemotherapy.
This less-is-more movement regarding chemotherapy is also informing research and treatment guidelines. National American guidelines now call for doctors to monitor older men with slow-growing prostate cancer, rather than administering chemotherapy. A 2011 study in the journal Therapeutic Advances Medical Oncology looking at chemotherapy and colorectal cancer noted: “We treat many patients without benefit, either because their cancer does not respond or because it has already been cured surgically.”
There is no question chemotherapy has saved and extended countless lives since it came into standard use and is a major reason survival rates have improved so dramatically for many cancers. But it takes a huge toll on patients.
Designed to kill fast-growing cancer cells, chemotherapy also attacks other cells, and the hair. Baldness is the most visible side-effect, but it is just one of them. It also kills cells in the lining of the intestines, for example, and cells in patients’ ovaries, rendering them infertile, which can magnify an already traumatic experience.
The treatment has also often been used with no real benefit. One estimate suggests that as many as 85 per cent of patients with the most common form of breast cancer — estrogen-positive and lymph node-negative — received unnecessary chemotherapy over the years.
Now, doctors are getting better at determining whether chemotherapy will actually benefit a patient and by how much, which helps patients decide whether it is worth it.
Dr. Angel Arnaout, a surgical oncologist at The Ottawa Hospital and a clinical investigator of cancer therapeutics at The Ottawa Hospital Research Institute, is studying the early use of hormone-blocking agents and more targeted treatments for breast cancer.
There is still a certain amount of estimation, using factors such as a patient’s age and the size of their tumour, when it comes to determining how effective chemotherapy would be. Arnaout’s research aims to take some of the guesswork out of that.
It involves administering anti-estrogen medication to breast cancer patients whose tumours are hormone sensitive (fed by hormones), immediately after diagnosis. The majority of breast cancer tumours fit this category. Traditionally, patients would be given this treatment in addition to chemotherapy, radiation and surgery. Arnaout’s research should help doctors better figure out whether the anti-estrogen therapy alone is sufficient so that chemotherapy can potentially be avoided.
“It makes sense that if you want to subject someone to six months of really difficult treatment, a lot of which has side-effects, you should at least figure out whether it will truly work and that there is no other less toxic alternative treatment, such as anti-hormonal therapy,” said Arnaout.
Clemons said mathematical modelling is helping more patients make informed decisions about chemotherapy but Arnaout’s work is “taking this to the next level. I think this is where the future really lies.”
“Being diagnosed with cancer is terrifying,” he said. “Sitting with a patient in my clinic who is convinced she is going to need chemotherapy, and I am saying to her the benefits are so small it’s not worth it, then when I see her smile and this relief come across her face … you know you are doing your job well.”
Smith was involved in Arnaout’s initial trial, which administered hormone blockers to patients as soon as they were diagnosed. Her findings were positive — in 49 per cent of patients, tumours were significantly suppressed or stopped growing within weeks, which suggests those patients would not need chemotherapy. Arnaout is due to begin a bigger trial later this year comparing patients who receive chemotherapy and hormone blocking therapy with those who simply received hormone blocking therapy.
Not only are the implications for avoiding chemotherapy positive, but, Arnaout said, patients were happy to begin any treatment immediately rather than waiting weeks.
“It was really good to feel that you were doing something in those three weeks (before surgery),” said Smith.
Arnaout said that in the future she hopes oncologists will have enough information about the genetic makeup of individual tumours and how they respond to hormone blockers that they will not even offer chemotherapy as an option.
“I think it is unfair to ask the patients to choose when they are in an anxious and confused state,” she said.
The medical world is already getting far better at using chemotherapy only when needed, says Clemons.
“Nobody in their right mind would want to do chemotherapy, but when you see the benefits are very real it makes the toxicity far more palatable.”
In 1990, Clemons said, a guideline went out in the United States saying that “there is no group of patients who do not benefit from chemotherapy.”
Over the years, he said, many oncologists “cursed that guideline because it probably led to such wide use of chemotherapy and probably many people were hurt.”
Arnaout calls the use of chemotherapy without knowing whether it is doing any good “the old way of doing things.
“The problem is that chemotherapy is not innocent. It is toxic and hard on the patients for a very long time.”
Chemo by the numbers
85: Percentage of breast cancer patients who were treated with traditional chemotherapy a decade ago, according to Ottawa medical oncologist Dr. Mark Clemons
50: Percentage of breast cancer patients who are treated with traditional chemotherapy today
80: Percentage of patients with estrogen-positive, lymph-node negative breast cancer — the most common type — believed to have received unnecessary chemotherapy treatments over the past 20 years
0: The number of cancer patients a 1990 U.S. directive said would not benefit from chemotherapy.
49: Percentage of patients in a trial conducted by Ottawa cancer researcher Dr. Angel Arnaout whose tumours responded so well to anti-hormonal therapy that they did not require chemotherapy