Featured Research

from universities, journals, and other organizations

New nuclear breast imaging technologies associated with higher cancer risks, study finds

Date:
August 24, 2010
Source:
Radiological Society of North America
Summary:
Some nuclear-based breast imaging exams may increase a woman's risk of developing radiation-induced cancer, according to new research. However, the radiation dose and risk from mammography are very low.

Some nuclear-based breast imaging exams may increase a woman's risk of developing radiation-induced cancer, according to a special report appearing online and in the October issue of Radiology. However, the radiation dose and risk from mammography are very low.

"A single breast-specific gamma imaging (BSGI) or positron emission mammography (PEM) examination carries a lifetime risk of inducing fatal cancer greater than or comparable to a lifetime of annual screening mammography starting at age 40," said the study's author, R. Edward Hendrick, Ph.D., clinical professor of radiology at the University of Colorado-Denver, School of Medicine in Aurora, Co.

The risks and benefits of screening mammography are under constant scrutiny. Meanwhile, newer breast imaging technologies, such as BSGI and PEM have been approved by the U.S. Food and Drug Administration (FDA) and introduced into clinical practice. Preliminary studies have shown both to be promising at detecting cancer; however, both involve the injection of radioactive material into the patient.

BSGI uses a high-resolution gamma camera that allows for imaging with mild compression of the breast along with an injection of a nuclear radiotracer, which is absorbed at a higher rate by cancerous cells. In PEM, radioactive material is injected into the body to measure metabolic activity and determine the presence of disease. Other technologies, not yet approved by the FDA, include dedicated breast CT and digital breast tomosynthesis.

Dr. Hendrick reviewed recent studies on radiation doses from radiologic procedures and organ doses from nuclear medicine procedures, along with Biologic Effects of Ionizing Radiation (BEIR) VII age-dependent risk data, to estimate the lifetime risk of radiation-induced cancer incidence and death from breast imaging exams using ionizing radiation.

Two-view digital mammography and screen-film mammography were found to have an average lifetime risk of fatal breast cancer of 1.3 and 1.7 cases, respectively, per 100,000 women aged 40 years at exposure and less than one case per one million women aged 80 years at exposure. Annual screening mammography (digital or screen-film) performed in women from age 40 to age 80 is associated with a lifetime risk of fatal breast cancer of 20 to 25 cases in 100,000.

"Two-thirds of mammography units in the U.S. are now digital, which, on average, exposes the patient to an even lower radiation dose than screen-film," Dr. Hendrick said. "Manufacturers and breast centers continue to take steps to lower radiation doses on digital mammography systems without negatively affecting image quality."

Dedicated breast CT and digital tomosynthesis were both found to have an average lifetime risk of fatal breast cancer of 1.3 to 2.6 cases, respectively, per 100,000 women 40 years of age at exposure.

A single BSGI exam was estimated to involve a lifetime risk of fatal cancer 20 to 30 times that of digital mammography in women aged 40 years, while the lifetime risk of a single PEM was 23 times greater than that of digital mammography. In addition, while mammography only slightly increases a woman's risk for breast cancer, BSGI and PEM may increase the risk of cancers in other organs as well, including the intestines, kidneys, bladder, gallbladder, uterus, ovaries and colon.

People are exposed to radiation from natural sources all the time. The average person in the U.S. receives an effective dose of about 3 millisieverts (mSv) per year from naturally occurring radioactive materials and cosmic radiation from outer space. The average effective dose from two-view screen-film (0.56 mSv) or digital mammography (0.44 mSv) is equivalent to approximately two months of natural background radiation, while the effective doses from BSGI (6.2 mSv) and PEM (9.4 mSv) exams equal approximately two to three years of natural background radiation exposure.

Currently, no one is advocating using PEM or BSGI as a screening method to replace mammography. These exams are typically performed on women with suspicious breast lesions and in women with dense breasts who are difficult to examine with other techniques. Despite the increased radiation dose, these exams have shown promise in detecting cancer accurately and may have a good risk-benefit ratio for some specific indications.

"The primary tool for breast cancer screening is still mammography, which has a very low radiation dose and a very low lifetime risk of cancer induction," Dr. Hendrick said. "The risk of missing a breast cancer because mammography is not done far outweighs the tiny risk of mammography causing a breast cancer."

He added that the subset of women under 40 who are known to be at higher risk of breast cancer should consider being screened with breast ultrasound or breast MRI, both of which deliver no ionizing radiation and have sensitivities to breast cancer that are unaffected by higher breast density.


Story Source:

The above story is based on materials provided by Radiological Society of North America. Note: Materials may be edited for content and length.


Cite This Page:

Radiological Society of North America. "New nuclear breast imaging technologies associated with higher cancer risks, study finds." ScienceDaily. ScienceDaily, 24 August 2010. <www.sciencedaily.com/releases/2010/08/100824082325.htm>.
Radiological Society of North America. (2010, August 24). New nuclear breast imaging technologies associated with higher cancer risks, study finds. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2010/08/100824082325.htm
Radiological Society of North America. "New nuclear breast imaging technologies associated with higher cancer risks, study finds." ScienceDaily. www.sciencedaily.com/releases/2010/08/100824082325.htm (accessed July 28, 2014).

Share This




More Health & Medicine News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

$15B Deal on Vets' Health Care Reached

$15B Deal on Vets' Health Care Reached

AP (July 28, 2014) A bipartisan deal to improve veterans health care would authorize at least $15 billion in emergency spending to fix a veterans program scandalized by long patient wait times and falsified records. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
West Africa Gripped by Deadly Ebola Outbreak

West Africa Gripped by Deadly Ebola Outbreak

AFP (July 28, 2014) The worst-ever outbreak of the deadly Ebola epidemic grips west Africa, killing hundreds. Duration: 00:48 Video provided by AFP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. 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:
from the past week

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