Survival rates among women with early breast cancer were better with lumpectomy and radiation than with mastectomy, a U.S. study suggests.
When researchers followed more than 112,000 women in California with early stage breast cancer for 14 years, they found women were more likely to survive breast cancer after having breast conserving surgery plus radiation than mastectomy.
"The findings in this study should reassure women that among all age groups and tumor types, lumpectomy continues to be an excellent choice for women with small early breast cancers, " study author Dr. Shelley Hwang of Duke Cancer Institute in Durham, N.C., said in a release.
The effect was strongest for women over age 50 with hormone-sensitive cancers, the study's authors said in Monday's issue of the journal Cancer.
"These findings support the notion that breast-conserving therapy, when combined with radiation, confers at least equivalent and perhaps even superior survival to mastectomy as definitive breast cancer treatment," they concluded.
Differences in mastectomy rates
The findings come as some women in the U.S., particularly those who are younger, affluent and living in cities are increasingly opting for mastectomy for very small cancers, the researchers said. They speculated that improvements in reconstructive techniques, changing attitudes toward mastectomy or a desire to reduce anxiety associated with long-term surveillance could be contributing to the trend in the U.S.
In Canada, mastectomy rates vary widely between provinces, with the highest rates reported among those living in the least affluent areas, the opposite of the U.S. trend. In a report last year, researchers with the Canadian Institute for Health Information and the Canadian Partnership Against Cancer suggested the long courses of radiation often recommended after lumpectomies and travel time could be reducing use of the less-invasive surgery.
Earlier randomized clinical trials showed equivalent survival for breast conserving surgery with radiation and mastectomy for early-stage breast cancer but didn't look at women in the general population.
In the latest study, 55 per cent of the women received lumpectomy and radiation, while 45 per cent had mastectomy without radiation.
Among those over 50 years old with hormone-sensitive breast cancers, the risk of dying from breast cancer during the follow-up was 14 per cent lower in the breast conserving group than similar cancers treated with mastectomy.
In the first three years after surgery, women who underwent mastectomy had a higher risk of dying from heart disease and other diseases than women who had lumpectomy. It's possible that those in the lumpectomy group were generally healthier, Hwang said.
Since the study was observational in nature, the link between breast-conserving treatment and survival is only an association and no cause-and-effect relationship can be drawn.
Surgical patterns changed over the course of the study, the authors noted. Factors such as tumour grade, race, tumour size and age at diagnosis were considered in the analysis.
The study was funded by the U.S. National Cancer Institute.
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One of the possible risk factors that is the most controversial in the world of breast cancer are the findings about soy's source of estrogen — which some say can even cause cancer. One thing is certain, the soybean and its derivatives — tofu, soymilk, tempeh (fermented soybeans) — are all interesting alternatives to meat because of their protein content and unsaturated fat levels. But other studies indicate that soybeans are rich in antioxidants known to prevent several cancers, including breast cancer itself. That being said, some studies indicate that it would be safer to consume soy before menopause and women with breast cancer or in remission should reduce soybean consumption or eat in moderation.
A scientific journal published in Advances in Nutrition in 2011, noted the importance of having zinc in your diet to boost the immune system and our DNA make-up. Until more scientific evidence is found, it would still be a good idea to add zinc-related foods to your dish like oysters, clams, butter sesame seeds, pumpkin seeds and legumes.
Well known for its role in calcium absorption, vitamin D has also been the subject of studies for cancer prevention. In the case of breast cancer, some studies have shown that vitamin D can even prevent it. On the contrary, other studies have not achieved the same results. That said, we also know that the treatment of breast cancer chemotherapy causes a loss of bone density in women pre-menopause. This is more of a reason to ensure an adequate intake of vitamin D, especially from October to March, when sunlight is rare. Try foods like fish, — especially canned with bones, milk, yogurt, vegetable drinks fortified with vitamin D, eggs and shiitake mushrooms.
Several studies have confirmed that women who consume alcohol on a regular basis increase their risk of being diagnosed with breast cancer. Even one drink a day raises the risk by four per cent. Those who have the habit of drinking three or more drinks a day saw their risk rise to over 40 per cent. That being said, moderation is key for cancer prevention.
Obesity significantly increases the risk of developing breast cancer, particularly in post-menopausal women. Being diagnosed with obesity at the time of breast cancer was associated with poorer survival, the study added.
Nursing can possibly help prevent breast cancer and lower it's risks, according to a report by About.com. On top of this, one 2002 study found that an estimated 25,000 breast cancers would be prevented in developed countries if women had the same number of children but breastfed each child for six months longer, the CBC reports.