Women with early stages of breast cancer often choose and are sent for chemotherapy. But should they? According to a new study, the current Canadian guidelines for the management of early-stage breast cancer-- breast cancer that has not spread to nearby lymph nodes or other parts of the body -- result in thousands of women receiving chemo without benefit.
Apparently, 90 per cent of the 22,600 patients whose breast cancer tests negative for human epidermal growth factor receptor 2 (HER2) should be offered chemo (as per clinical guidelines) even though only an estimated 15 percent of those cancers will actually recur. This suggests that each year about 8,500 patients may be unnecessarily subjected to the toxicity of chemo, treated with no benefit to them.
The study, published in the journal Current Oncology, was led by Dr. Yvonne Bombard, a genomics and health services researcher in the Li Ka Shing Knowledge Institute of St. Michael's Hospital in Toronto. Her team recruited early-stage breast cancer patients who had completed surgical treatment and who were offered gene expression profiling (GEP) tests.
GEP tests can help differentiate women who might benefit from chemo versus those who might not. The test analyzes patterns of 21 different genes within the cancer cells to help predict how likely it is that a woman's cancer will recur within ten years after initial treatment and how beneficial chemo will be to her. Her risk of recurrence is then scored as low, intermediate or high. If the recurrence score is low, the patient likely will derive little or no benefit from added chemo; if her recurrence score is high, chemo should be of benefit.
Dr. Bombard said women she interviewed understood the concept that the test could indicate whether chemo would be beneficial or not. But she also found that many women thought the test reflected their own unique circumstances and did not understand that their test result was actually based on larger population statistics. In other words, they saw the test as providing more personalized information than what they'd get from typical population statistics, but they didn't comprehend that these tests are themselves actually based on population statistics.
One woman told Dr. Bombard that before her GEP test she was uncomfortable with the notion that her chemo treatment decision would be based on traditional risk markers such as tumour size, tumour grade, and nodal involvement. She and others believed the GEP information was unique to them in contrast to the statistical estimates they received from pathology reports.
Women placed a huge emphasis on GEP when making chemo decisions, without actually fully understanding the test. Women valued GEP because they thought it provided them with certainty amid confusion, with options and a sense of empowerment. "Patients often viewed their GEP results as providing information that was more scientifically valid, uniquely personalized and emotionally significant than any other information they had received," Dr. Bombard said. But these tests are meant to complement, not replace, other tests. "The GEP test is just one more piece of information."
Patients were even uncomfortable about acknowledging that GEP tests offered but one piece of the treatment puzzle and that its results should be considered in concert with other factors such as tumor size, receptor status, nodal involvement. Not only did patients tend to over-estimate the truth-value of GEP testing, but this study also showed that patients make very deep emotional investments in GEP test results. The study's results "identify a need for communication or decision aids to support patients' understanding of the test and its limitations," Dr. Bombard noted.
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Breast cancer, in its simplest definition, is cancer that starts in the cells of the breast. But what we call "breast cancer" actually includes several different types of cancer, all of which require different treatments and have different prognoses.
Most breast lumps indicate something other than breast cancer—some possible causes for breast lumps include cysts, fibrosis, or benign tumours. And some women are just prone to lumpy breasts, which is stressful but harmless. That said, if you find a lump, get it checked out — know that the odds are good that it's nothing serious, but see your doctor about it for your own peace of mind.
It's helpful to know that breast cancer can appear in forms other than a lump, which means there are other physical signs you should watch for. Other symptoms that you should get checked out include thickening of the skin in the breast or underarm area; swelling, warmth, redness, or darkening of the breasts; a change in your breast size or shape; dimpling or puckering of the breast skin; an itchy, scaly sore or rash on the nipple; a pulling in of your nipple or another part of your breast; sudden nipple discharge; or pain in one spot of the breast that doesn't go away.
A family history of breast cancer (on either your mother or father's side) can be an indication that your personal odds of developing it are higher than average, but they don't guarantee that you will. As well, the majority of women who develop breast cancer have no identifiable risk factors, including family history. And the BRCA1 and BRCA2 gene mutations are hereditary, but only account for five to 10 per cent of all breast cancers.
The news that Angelina Jolie had had a preventative double mastectomy after testing positive for the BRCA1 gene mutation made many women wonder if they had the same mutation--and what it would mean for them if they did. If you do have the BRCA1 or BRCA2 gene mutation, your lifetime risk of developing breast cancer or ovarian cancer is significantly elevated, and women with the mutations who do get cancer tend to develop it at younger ages; one estimate states that 55 to 65 per cent of the women with the BRCA1 mutation and 45 per cent of those with the BRCA2 mutation will develop breast cancer by age 70, versus 12 per cent in the general population. But it does not mean that cancer is definitely in your future, and every person has to make her own individual decision, based on a variety of factors, about how to best mitigate her risk of disease.
This often-cited statistic is somewhat misleading. Breast cancer risk varies based on a variety of factors, including age, weight, and ethnic background. Risk increases as you get older (http://www.cdc.gov/cancer/breast/statistics/age.htm): most breast-cancer cases are in women in their 50s and 60s. Also, some ethnic groups appear to be more susceptible to breast cancer; the National Cancer Institute in the U.S. says that white, non-Hispanic women have the highest overall risk of developing breast cancer, while women of Korean descent have the lowest risk, but African-American women have a higher death rate. Finally, being overweight or obese may also up your risk; there is evidence that being obese or overweight after menopause can up your breast-cancer risk, possibly because fat tissue is a source of estrogen.
You can't prevent breast cancer, per se, but there are ways to lower your personal risk. If you are overweight or obese, you could try to lose weight in a healthful way; if you are already in a healthy weight range, try to stay there. Exercise regularly, as as little as 75 to 150 minutes of walking a week has been shown to have a lowering effect on risk. Limit your alcohol consumption — research found that women who have two or more alcoholic drinks each day have an elevated risk of breast cancer. And avoid hormone therapy during menopause, as a combo of estrogen and progestin has been shown to raise breast-cancer risk.
Mammograms are a powerful way to detect breast cancer early on, but they aren't 100 per cent. Mammograms are most effective in women aged 50 and over; they detect about 83 per cent of women who have breast cancer in that age group. For younger women, the sensitivity is 78 per cent. However, that does mean some cancers are missed and that there are false-positive results as well, which could require a biopsy to confirm. Talk to your doctor about when you should start getting mammograms regularly, or if you have symptoms that suggest that you should get one.
Some wondered if Giuliana Rancic's fertility treatments were behind her diagnosis of breast cancer in her late 30s, but experts interviewed by WebMD said that there is no strong evidence connecting the disease with the use of fertility drugs. It's true that hormonal treatments can raise the risk for post-menopausal women, but women undergoing fertility treatments are almost never in that age range, and also take the medications for a much shorter period of time.
Cancer is scary, but in most cases, women who are diagnosed with breast cancer survive and lead healthy lives. According to the Breast Cancer Society of Canada, the five-year survival rate is 80 per cent for men and 88 per cent for women. That's up from 79 per cent for women in 1986.
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