Looking beyond screening mammography in the war against breast cancer.

Courtesy: MariaShriver.com 

Whenever we think of breast imaging, our first thought is mammography. The earliest record of mammography dates back to 1913 when German Surgeon Albert Salomon attempted to visualize cancer through radiogram but it was only in mid 60s that  mammography was introduced as a screening tool on mass scale for early diagnosis of breast cancer.

The technique has substantially evolved in last several decades, from direct-exposure films to digital. Digital mammography exposes the patient to much lower dose of radiation as compared to analog mammography and the images are clearer and can be viewed on computer.

New data analysis R. Edward Hendrick, Ph.D., shows nearly 275,000 breast cancer deaths have been averted since 1990, attributed to increased mammographic screening and improved therapies.

However, like other techniques, mammography is also not perfect and has its own limitations. 

According to ACS screening mammograms do not find about 1 in 5 breast cancers. Chances of missing the disease is higher if the patient have dense breast.

A recent study has shown that nearly 43% patients in USA have dense breast.

Many US states have laws requiring the mammography centers to inform patients about dense fibroglandular breast tissue and its impact on cancer diagnosis and detection rates.

courtesy of Hologic

Digital breast tomosynthesis (DBT) or 3D mammography is a new technique for mammography especially useful for screening women with dense breast. It includes multiple low-dose full-field projection images of the breast obtained from different angles that form an arc. The images are then used to reconstruct a 3D image of the breast, resulting in a clearer view without the distraction of overlapping tissue.

Currently there are four tomosynthesis systems on the market. Hologic’s Selenia Dimensions mammography, GE’s SenoClaire 3-D breast tomosynthesis, Siemens Mammomat Inspiration Prime with Tomosynthesis Option and Fujifilm Medical Systems U.S.A.

Another screening technique is whole breast ultrasound and breast magnetic resonance imaging (MRI).

Whole breast ultrasound is used along with screening mammography to pick up lesions that cannot be felt by hands and also not seen on mammography. It is done in the same sitting as screening mammogram. It is specifically useful for patients whose mammogram reported “Extremely dense breasts” (or density score of 4) or “Heterogeneously dense breasts” (or density score of 3).

It can be performed manually or by using Automated Breast Ultrasound System(ABUS).

GE Introduced a new version of its automated breast ultrasound system ‘the Invenia Automated Breast Ultrasound System(ABUS)’.

Breast MRI is another screening tool, it is not recommended for routine screening because it results in more false positives leading to anxiety and unnecessary breast biopsies.  It is recommended for screening women who are at high risk for breast cancer, usually due to a strong family history and/or a mutation in genes such as BRCA1 or BRCA2.

The American Cancer Society (ACS) recommends that all high-risk women with greater than 20% lifetime risk of breast cancer should have a breast MRI and a mammogram every year. For most women, these combined screenings should start at age 30 and continue as long as the woman is in good health.

Combined these three techniques are able to find another 20-40 percent more cancers than screening mammography alone.

Major American medical organizations with expertise in breast cancer care, including the American Congress of Obstetricians and Gynecologists (ACOG), American College of Radiology (ACR) and Society of Breast Imaging (SBI) continue to recommend that women start getting annual mammograms at age 40 and continue screening till women is in good health or life expectancy is less than 10 years.  

USPSTF advises to start screening at age 50 till 74 years with an interval of 2 years between screening.