Early stage breast cancer can be cured in most women
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Question: I was just diagnosed with breast cancer. My doctor said I have DCIS with micro invasion on the right breast. What does that mean? I am very scared – and I’m especially worried about the possibility of needing radiation therapy after surgery. I’ve heard that treatment can be very difficult.
Answer: It’s totally understandable that you feel scared. No one welcomes a diagnosis of cancer. However, it sounds like you are in a very early stage of the disease and you should have an extremely good chance of being cured.
DCIS stands for ductal carcinoma in-situ, which means cancerous cells have started to grow within one of the milk-ducts of your breast. If the cells were still confined to the milk duct, you would be classified as having a Stage 0 breast cancer. But your doctor has indicated that some cancer cells have spread into the surrounding breast tissue – hence, the term ‘micro’ invasion.
You basically have Stage 1 breast cancer and that suggests you have an excellent chance of a successful outcome, says Dr. Frances Wright, a breast cancer surgeon at Sunnybrook Health Sciences Centre.
“A Stage 1 breast cancer causes tremendous anxiety among patients,” she says. “There is a lot of fear – which I understand – because who wants cancer?”
But, she adds, major treatment advances have been made in recent years and patients’ prospects are much more promising than they used to be.
In fact, the five-year survival rate for women diagnosed with Stage 1 breast cancer is 99 per cent, says Dr. Prithwish De, an epidemiologist with the Canadian Cancer Society.
“The five-year mark is usually used as the measure of a cure,” he explains, and the cancer is considered to be gone from the body. If a patient receives a cancer diagnosis after that period of time has passed, it is usually thought to be a brand new cancer, unrelated to the first bout of the disease.
Of course, this is the average survival rate for women in the population. Some individuals may have certain risk factors – such as genetic mutations– that make them especially vulnerable to cancer re-occurrence or they may be prone to aggressive forms of the disease. A woman’s age, response to treatment and previous medical history, can also affect her prognosis.
In general though, women diagnosed with Stage 1 – in which the tumour is two centimeters or smaller in size and the cancer has not spread outside the breast – can be fairly optimistic they will beat the disease.
The odds are also very good for Stage 2 in which the cancer has reached the lymph nodes. The five-year survival rate for this group is about 86 per cent.
Doctors divide cancer into 4 distinct stages – although you will sometimes see it broken down into sub-categories such as Stages 1A and 1B.
As you might expect, the chances of survival decrease as the disease becomes more advanced.
For Stage 3 – in which the cancer has spread to nearby tissue outside the breast such as the chest wall – the survival rate drops down to 57 per cent.
And for Stage 4 – in which the cancer has metastasized, spreading to distant parts of the body – the 5-year survival is about 20 per cent.
The encouraging news is that the vast majority of breast cancer cases in Canada – about 80 per cent – are diagnosed when they are still in the early stages, either 1 or 2.
By drawing attention to these rosy statistics, I don’t mean to minimize the seriousness of the disease or to downplay the huge upheaval it causes in the lives of individual women and their families. About 24,000 women are diagnosed with breast cancer in Canada each year and it’s responsible for about 5,000 deaths annually.
But it’s clear that significant progress is being made in the fight against breast cancer.
Back in the 1960s, the combined five-year survival rate for all four stages of breast cancer was 58 per cent in Canada. By the mid-1980s, that figure had climbed to 73 per cent. Today it’s up to 80 per cent.
Part of those gains can be attributed to the introduction throughout Canada during the late 1980s and early 1990s of population-wide mammogram-screening programs that have led to an improvement in early detection of the disease in many women.
Experts also point to a much wider array of effective treatments that tend to be less onerous than past therapies.
“For early-stage breast cancer, a patient can usually get a lumpectomy rather than a mastectomy, which used to be the standard practice several decades ago. So treatments are less radical than they used to be – but no less effective,” says Dr. De. “There is less pain, fewer side effects, and a faster recovery,” he adds.
(In a lumpectomy, only the tumour and a small margin of surrounding normal tissue are removed, along with a few lymph nodes for testing. A mastectomy involves the surgical removal of the entire breast and all the lymph nodes in the armpit.)
When it comes to drug treatments, or chemotherapy, some of the newer medications are tailored to deal with very specific aspects of the patient’s cancer.
For instance, many women have a form of breast cancer that’s fuelled by hormones, such as estrogen circulating in the body. After the initial surgery, tumour samples are examined in the lab for the presence of estrogen receptors. The results of these tests will determine if a woman would be a good candidate for a drug like Tamoxifen, which binds to the hormone receptors – and prevents the real estrogen from acting on the tumour. Tamoxifen can slow or stop the growth of cancer cells and is considered highly effective in lowering the risk of breast cancer recurrence.
(For post-menopausal women with hormone-sensitive tumours, doctors may prescribe a class of drugs known as aromatase inhibitors, instead of Tamoxifen. They work differently than Tamoxifen but generally achieve the same result; they lower estrogen levels.)
Herceptin is another drug that can help put the brakes on uncontrolled cancer growth. It is used in women who have a gene that leads to an excessive number of HER2 receptors on the surface of the cancer cells. These receptors pick up growth signals and spur on the tumour. By blocking HER2 receptors, Herceptin can slow or stop the growth of the breast cancer.
“The drugs today are much more targeted and treatments are selected based on the woman’s genetic make-up,” says Dr. De.
In other words, cancer therapy is moving towards a personalized approach. And the newer, more specialized, medicines tend to have fewer side effects than the earlier forms of broad-acting chemotherapy – which were disparagingly referred to as “slash, burn and poison” treatments.
There have also been significant changes in post-operative radiation therapy – which you raised as one of your chief worries.
Typically the radiation is focused on a smaller area, using a higher dose for a shorter period of time, said Dr. De. This approach helps to reduce side effects and limits the damage done to surrounding healthy tissue. “Usually radiation is tolerated very well by patients. The main side effects are fatigue and 1 in 10 women will get a ‘sunburn’ from the radiation,” says Dr. Wright.
Aside from the cancer treatments, we now know that adopting certain lifestyles can affect a woman’s chances of keeping cancer at bay. Two large clinical trials have shown that a low-fat diet and regular exercise can reduce the risk of recurrence and lower the chance of death in women with early-stage cancer.
“This type of information wasn’t available in the past, but these are things that we can now recommend to women as they are going through their cancer journey,” says Dr. De.
It should also be noted that not smoking tobacco increases the likelihood that your cancer treatment will work.
I hope this overview of improved survival rates and increased treatment options alleviate some of your fears.
As Dr. De puts it: “The arsenal of tools available for treatment has grown tremendously over the past several decades. And women with breast cancer today are certainly benefiting from those advances.”
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Paul Taylor, Sunnybrook’s Patient Navigation Advisor, provides advice and answers questions from patients and their families. His blog, Personal Health Navigator, is reprinted on Healthy Debate with the kind permission of Sunnybrook Health Sciences Centre. Follow Paul on Twitter @epaultaylor.