During the month dedicated for global breast cancer awareness, a new study on mammograms is churning up discussions on whether breast cancer screening may lead to overdiagnosis and hence treatment deemed unnecessary.

Researchers collating data gathered by the U.S. National Cancer Institute from 1975 to 2012,discovered that mammograms were more likely to result in cases of overdiagnosed breast cancer, rather than serving the intended purpose of the screening being the early detection of a small tumour destined to grow in size, prior to the tumour actually showing symptoms.

Some develop aggressive forms of cancer that cannot be caught early


What may appear to be non-compliant behaviour to the rrecommended once-in-two-years mammogram screening may essentially entail better reasoning as “Mammography can help very few women, but it comes at a real human cost, including people undergoing treatment unnecessarily,” said one of the lead authors, Dr. H. Gilbert Welch of the Dartmouth Institute for Health Policy.

After actress Angelina Jolie disclosed in 2013 that she has a gene mutation which put her at risk for breast and ovarian cancer, between 80 and 100 women in Singapore have asked to be tested each year. Whereas “only five to 10 women here would test for it each year,” said Dr Lee Soo Chin, a senior oncologist researcher at the National University Cancer Institute, Singapore.

According to the Singapore Cancer Registry more than 9,000 new cases of breast cancer were diagnosed between 2010 and 2014 making it the most common cancer among women in Singapore. Despite the remarkably high incidence, less than 40% of older women in Singapore have gotten themselves screened for breast cancer in the past two years, according to the Health Promotion Board.

Mammograms can lead to detrimental outcomes


The Dartmouth study also found that the value of mammograms as a life-saving tool has been significantly overstated. Instead, the introduction of more effective treatments should get most of the credit for improving survival rates among women diagnosed with breast cancer, the researchers concluded.

Since our screening technology still cannot identify which cancers are likely to change into something lethal and which are better left alone to disappear on their own, all breast cancers that get detected are generally opted for treatment.

This translates into to a lot of unnecessary procedures such as invasive biopsies, mastectomies, radiation, and chemotherapy in the extreme cases for women whose lives would otherwise have been healthy.

Death rate decline not completely attributable to screenings


The next question posed by the general public then would be pertaining to today’s significantly lower death rate for breast cancer. The same group of researchers concluded that it is mainly due to factors such as improved treatments rather than early detection through mammograms.

The study fuelled the already fierce debate over how often and which group of women should get mammograms, a controversy that has sparked the interest of not just policymakers, and physicians, but particularly their female patients as well.

American Cancer Society warns the study “must be viewed with caution”


The report is the latest study to undermine the once-strong consensus that regular screenings are crucial to safeguarding women’s health. Just in the past two years, a major study of Norwegian breast cancer patients found that routine mammograms reduced the risk of dying from breast cancer by less than 10% while another study found no effect on death rates when comparing European nations where screening became prevalent in the 1990s with those where it became widespread in the 2000s.

Archie Bleyer, a professor at the Knight Cancer Institute at Oregon Health & Science University who is the study’s other co-author, said he is not suggesting that that women stopped getting mammograms altogether. “There are clearly women who are benefiting from doing this,” he said.

These findings do suggest that the message to women about mammograms needs to be more nuanced. Women in their 40s who feel comfortable getting annual mammograms should not be discouraged from doing so. However, women who have never felt good about it or who feel they are being coerced into the procedure, should not be made to feel guilty about negligence of own health. MIMS

Read more:
Post-mastectomy radiation therapy now has better defined guidelines
Bravely battling breast cancer on a beauty pageant platform
When was the last time you checked your breasts?

Sources:
http://www.straitstimes.com/singapore/jolie-effect-more-in-singapore-doing-gene-test-for-cancer
http://www.latimes.com/science/sciencenow/la-sci-sn-breast-cancer-screening-mammograms-20161012-snap-story.html
http://www.channelnewsasia.com/news/singapore/less-than-40-of-older-women-get-breast-cancer-screening/3159456.html
http://naturalsciencenews.com/2016/10/13/researchers-caution-that-mammograms-sometimes-do-more-harm-than-good/