Featured Research

from universities, journals, and other organizations

Mammography has led to fewer late-stage breast cancers

Date:
June 10, 2014
Source:
University of Michigan Health System
Summary:
In the last 30 years, since mammography was introduced, late-stage breast cancer incidence has decreased by 37 percent, a new study finds. The analysis takes into account an observed underlying trend of increased breast cancer incidence present since the 1940s, a sort of inflation rate for breast cancer.

In the last 30 years, since mammography was introduced, late-stage breast cancer incidence has decreased by 37 percent, a new study from the University of Michigan Comprehensive Cancer Center finds.

Related Articles


The analysis takes into account an observed underlying trend of increased breast cancer incidence present since the 1940s, a sort of inflation rate for breast cancer.

Researchers looked at early-stage and late-stage breast cancer diagnoses between 1977-1979, before mammography became popular, and compared it to diagnoses between 2007-2009. Based on trends observed in the pre-mammography period of the 1940s to the 1970s as well as continued trends over time, the researchers took into account a central estimated increase in breast cancer incidence of 1.3 percent per year. This is called an annual percentage change, or APC.

Think of the APC like the inflation rate: $1 from 1977 does not go as far in 2007. Just as the cost of money rises, the number of breast cancer diagnoses is increasing, independently of efforts to detect it earlier.

In the current paper, published in Cancer, the researchers looked at the late 1970s data and projected incidence of early-stage and late-stage breast cancer in 2007-2009 based on the APC. They then compared the projected rates to actual rates.

Late-stage breast cancer incidence decreased 37 percent from the projected rate, and early-stage breast cancer incidence correspondingly increased 48 percent from 1977-1979 to 2007-2009. They also conducted similar analyses with other APC values, ranging from 0.5 percent to 2 percent. All estimates showed a substantial decrease in late-stage disease.

"When you factor in this temporal trend, our analysis shows that there has been a shift from late-stage to early-stage breast cancer over the last 30 years. This is what you would expect with a successful screening program. Not only are we detecting more early-stage cancer, but we are decreasing the number of late-stage cases that tend to be more challenging to treat and more deadly," says senior study author Mark Helvie, M.D., professor of radiology and director of breast imaging at the U-M Comprehensive Cancer Center.

There are many reasons why breast cancer incidence is increasing over time, including reproductive, dietary and environmental factors. Prior estimates showed a 1 percent to 3 percent annual increase in the United States and Europe before mammography screening began. In countries in Africa, Asia and Eastern Europe with no routine screening mammography, breast cancer rates are increasing as much as 3 percent to 5 percent per year.

Importantly, the current study also found that since mammography was introduced, there has been an overall 9 percent decrease in invasive breast cancer, when factoring in a 1.3 percent annual percentage increase. This has been offset by an increase in ductal carcinoma in situ, so-called stage 0 breast cancer, which is not invasive.

"While we have seen an increase in overall breast cancer incidence over the last 30 years, the drop in late-stage diagnoses is a positive benefit of mammography and our heightened awareness of early detection. The decrease in late-stage disease, together with improved treatments, contributes to the decreased mortality from breast cancer in the United States in the last 20 years," Helvie says.


Story Source:

The above story is based on materials provided by University of Michigan Health System. Note: Materials may be edited for content and length.


Journal Reference:

  1. Mark A. Helvie, Joanne T. Chang, R. Edward Hendrick, Mousumi Banerjee. Reduction in late-stage breast cancer incidence in the mammography era: Implications for overdiagnosis of invasive cancer. Cancer, 2014; DOI: 10.1002/cncr.28784

Cite This Page:

University of Michigan Health System. "Mammography has led to fewer late-stage breast cancers." ScienceDaily. ScienceDaily, 10 June 2014. <www.sciencedaily.com/releases/2014/06/140610112347.htm>.
University of Michigan Health System. (2014, June 10). Mammography has led to fewer late-stage breast cancers. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2014/06/140610112347.htm
University of Michigan Health System. "Mammography has led to fewer late-stage breast cancers." ScienceDaily. www.sciencedaily.com/releases/2014/06/140610112347.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) — The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) — Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com
Madagascar Working to Contain Plague Outbreak

Madagascar Working to Contain Plague Outbreak

AFP (Nov. 24, 2014) — Madagascar said Monday it is trying to contain an outbreak of plague -- similar to the Black Death that swept Medieval Europe -- that has killed 40 people and is spreading to the capital Antananarivo. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Are Female Bosses More Likely To Be Depressed?

Are Female Bosses More Likely To Be Depressed?

Newsy (Nov. 24, 2014) — A new study links greater authority with increased depressive symptoms among women in the workplace. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins