Navigation Links
Routine mammograms may result in significant overdiagnosis of invasive breast cancer

Boston, MA New Harvard School of Public Health (HSPH) research suggests that routine mammography screeninglong viewed as an essential tool in detecting early breast cancersmay in fact lead to a significant amount of overdiagnosis of disease that would otherwise have proved harmless. Based on a study of women in Norway, the researchers estimate that between 15% and 25% of breast cancer cases are overdiagnosed.

The study appears in the April 3, 2012 issue of the Annals of Internal Medicine.

"Mammography might not be appropriate for use in breast cancer screening because it cannot distinguish between progressive and non-progressive cancer," said lead author Mette Kalager, a visiting scientist at HSPH and a researcher at the Telemark Hospital in Norway. "Radiologists have been trained to find even the smallest of tumors in a bid to detect as many cancers as possible to be able to cure breast cancer. However, the present study adds to the increasing body of evidence that this practice has caused a problem for womendiagnosis of breast cancer that wouldn't cause symptoms or death."

Most women in the U.S. begin having annual mammograms in their 40s or 50s. But recent research suggesting evidence of overdiagnosis has increased debate about the benefits of screening. A number of experts have speculated that new effective treatments for breast cancer play a larger role in saving women's lives than screening doesand have noted that overdiagnosis can cause unnecessary stress and unnecessary medical treatment.

Kalager says the new findings suggest that women should be well-informed not only about the potential benefit from mammography, but also about its possible harmsincluding mental distress, biopsies, surgeries, or chemotherapy and hormone treatments for disease that would never have caused symptoms.

The researchers analyzed data from 39,888 women with invasive breast cancer in Norway, 7,793 of whom were diagnosed during the 10-year rollout of the Norwegian Breast Cancer Screening Program, which began in 1996, for women ages 50 through 69. Because the screening program was phased in over time, the researchers were able to compare the number of breast cancer cases in women who had been offered screening with those not offered screening. The remaining study population consisted of two historical-comparison groupsmirroring the current groupsof women diagnosed with breast cancer from 1986 through 1995, before the nationwide program began.

The researchers theorized that if mammography is beneficial, it would lead to a decrease in late-stage breast cancer casesthe theory being that early detection prevents late-stage disease.

But the researchers did not find a reduction in late-stage disease in women who'd been offered screening. They did find, though, a substantial amount of overdiagnosis; among the 7,793 women diagnosed with breast cancer through participation in the screening program, 15% to 25% were overdiagnosedbetween 1,169 and 1,948 women. Based on those numbers, they further estimated that, for every 2,500 women invited to screening, 2,470 to 2,474 will never be diagnosed with breast cancer and 2,499 will never die from breast cancer. Only one death from breast cancer will be prevented. But 6 to 10 women will be overdiagnosed, and treated with surgery, radiation therapy, and possibly chemotherapy without any benefit.

Other HSPH authors included senior author Rulla Tamimi, assistant professor in the Department of Epidemiology, and Hans Olov-Adami, professor of epidemiology.

Support for the study was provided by the Norwegian Research Council and Frontier Science.


Contact: Marge Dwyer
Harvard School of Public Health

Related medicine news :

1. Two Studies Find Routine Mammography Saves Lives
2. For Sleep Struggles, Women Urged to Alter Routines
3. Routine follow-up scans can detect head and neck cancer recurrences earlier
4. For Some Couples, Binge Drinking Is Routine
5. Study shows hospice caregivers need routine care interventions
6. New Canadian Guidelines Also Support No Routine Mammograms Until 50
7. Routine Head Hits in Sports May Injure Brain, Experts Warn
8. Routine head hits in school sports may cause brain injury
9. Integrating medication regimens into daily routines can improve adherence
10. Routine Chores Might Help Keep Dementia at Bay
11. Troubled Teens Spotted in Routine School Screenings: Study
Post Your Comments:
(Date:6/25/2016)... ... June 25, 2016 , ... Austin residents seeking Mohs surgery services, ... Mohs Surgery and to Dr. Russell Peckham for medical and surgical dermatology. , Dr. ... skin cancer. The selective fellowship in Mohs Micrographic Surgery completed by Dr. Dorsey was ...
(Date:6/25/2016)... ... June 25, 2016 , ... ... non-athletes recover from injury. Recently, he has implemented orthobiologic procedures as a method ... —Johnson is one of the first doctors to perform the treatment. Orthobiologics are ...
(Date:6/24/2016)... ... June 24, 2016 , ... June 19, 2016 is World ... with chronic pain and the benefits of holistic treatments, Serenity Recovery Center ... with Sickle Cell Disease. , Sickle Cell Disease (SCD) is a disorder of the ...
(Date:6/24/2016)... Diego, CA (PRWEB) , ... June 24, 2016 , ... ... with the American Cancer Society and the Road To Recovery® program to drive cancer ... to seniors and other adults to ensure the highest quality of life and ongoing ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... Grove Investment Group (TGIG), has initiated cultivation and processing operations at its production ... and Pahrump, Nevada. , Puradigm is the manufacturer of a complete system of ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... Research and Markets has announced the addition of ... their offering. The current ... environment for MedImmune to enter. The US ageing population creates ... drive considerable growth for effective anti-influenza medications. The introduction of ... but development is still in its infancy. ...
(Date:6/23/2016)... PARK RIDGE, Ill. and INDIANAPOLIS ... caliber of students receiving a Lilly Diabetes Tomorrow,s Leaders ... hands. The 2016 scholarship winners, announced today online at ... refused to let type 1 diabetes stand in the ... Lilly Diabetes has supported the Foundation,s scholarship program since ...
(Date:6/23/2016)... N.J. , June 23, 2016  Guerbet announced ... Premier Inc.,s Supplier Horizon Award . ... year, Guerbet was recognized for its support of Premier ... creation through clinical excellence, and commitment to lower costs. ... to receive this recognition of our outstanding customer service ...
Breaking Medicine Technology: