3 Myths of Mammography
There is a lot of confusion and misinformation regarding screening mammography and breast cancer.
Here are a few myths I encounter when dealing with my patients.
Dr. Lisa Paulis, Elizabeth Wende Breast Care
Mammography is ineffective in screening for cancer in women
with dense breast tissue
Breast density is determined by the proportion of fat and glandular tissue in the breast. The more glandular tissue a patient has, the more “dense” the tissue is graded. Each patient is assigned a breast density classification on their mammogram which ranges from entirely fatty issue to extremely dense glandular tissue. The sensitivity of mammography is decreased in patients with dense tissue as the glandular tissue can obscure small cancers. However, tomosynthesis has been beneficial in this subgroup of patients. In addition, supplemental screening ultrasound has been effective in identifying an additional three to five cancers per 1000 women screened. Mammograms remain the most accurate tool available to diagnose ductal carcinoma in situ or DCIS which often shows up as calcifications and can be the earliest form of breast cancer we can detect. In patients with dense tissue, consideration should be given to screening mammography accompanied by ultrasound to offer the most comprehensive benefits of imaging.
Major health organizations, such as the American Cancer Society, as well as our local imaging community continue to recommend that women should be screened annually beginning at age 40. For more information go to sbi-online.org and talk to your healthcare provider.
Screening mammography should not be performed
in younger patients (ages 40-50) due to false positive results
A false positive is an area that appears abnormal on initial imaging but represents normal tissue on subsequent studies. False positives can lead to additional testing some of which can be invasive to determine a true result. In mammography, false positive results can mean anything from additional mammographic views, after which most patients will not require further workup, to ultrasound or minimally invasive biopsy procedures. In 2012 the percentage of patients requiring additional testing at our facility was approximately 10% mimicking the accompanying graphic. With the advent of tomosynthesis, which we perform with every mammogram, our recall rate has dropped to 5%. We feel strongly that women should be aware of these statistics to make an informed decision on how they weigh the risk of being one of the 5 out of 100 women who potentially needs additional views versus the risk of not screening. Of note, 12% of the cancers we diagnosed in our community in 2018 were in 40 year old women.
Annual screening mammography is only important for patients
with a family history of breast cancer
75% of women diagnosed with breast cancer have NO family history of the disease and are not considered high risk. In the general population 12% of women will develop breast cancer in their lifetime and 42,000 Americans will die from breast cancer this year.
Women who are at a higher than average risk due to personal or family history, prior atypical biopsy results, certain genetic factors etc. may benefit from additional screening (ultrasound, MRI) and/or genetic counseling. However, the absence of risk factors should not prevent a patient from pursuing screening imaging. In our local patient population only 4% of the patients we diagnosed last year had a known gene mutation.