The American Cancer Society (ACS) estimates that this year more than 211,000 new cases of breast cancer will be diagnosed in women in the United States. Breast cancer can affect males, but the disease strikes women about 100 times as often as it does men. Although statistics on breast cancer may be alarming, mortality rates have declined since 1990, according to the ACS. The decreases are attributable to earlier detection, the regular use of screening mammography, and better treatment.

Physicians will tell you that a second opinion is often valuable, and now radiologists at John Muir Health have a computer-aided tool to help them analyze mammograms with the innovative new ImageChecker®, a sophisticated Computer Aided Detection (CAD) imaging tool from R2 Technology, Inc. This tool is an important complement to mammography screening as national studies have demonstrated that some early-stage breast cancers may pass undetected in mammograms.

How Accurate Are Mammograms?

"Mammography has proven to be the single most beneficial tool in detecting early and treatable cancer," says Howard Cohen, M.D., a radiologist with John Muir Health. "It has resulted in a 30 to 35 percent lower mortality rate over the last several years, according to the American College of Radiology." While mammography may not be an exact science, a recent major study showed a 42 percent reduction in the number of women diagnosed with stage II or higher breast cancer among those women who underwent screening mammography.

Still, several factors such as the complex nature of the breast and observational oversights can contribute to false negatives or positives. Like a fingerprint, the appearance of the breast on a mammogram varies a great deal from woman to woman.

Since a mammogram doesn't distinguish a benign finding from a malignant one, improving the ability to identify early changes on a mammogram which may indicate the presence of a cancer is a key factor in producing successful therapeutic outcomes. There is good news: breast cancer is usually a slow-moving disease. If it is caught early and hasn't spread to the lymph nodes, the five-year survival rate is 97 percent, dropping to 78 percent if it spreads locally, according to the American College of Radiology.

How Does CAD Improve On Mammography Screening?

Although ImageChecker® is not a diagnostic instrument, it produces images on two video display monitors and points out clusters of spots, which may represent tiny calcifications, or focal areas of density which may represent a mass. The clusters are designated with a triangle, while dense areas are marked with an asterisk to draw the attention of the radiologist after initial review of the mammogram.

Using this advanced visual analysis software to identify subtle changes in images on a mammogram, the ImageChecker® system highlights areas of potential concern. "It serves as a second set of eyes for radiologists, developing algorithms to help us detect clusters of calcifications or masses which may indicate cancer," says Vivian Wing, M.D., a radiologist with John Muir Health. "The technology highlights potential problems and allows the radiologist to take a second look at abnormalities that may require further evaluation, such as a biopsy."

What Does CAD Require?

The system does not require patients to undergo additional steps during a mammogram, nor does it markedly increase demands on the time or attention of the reviewing radiologist. But mammography supplemented with CAD can improve the identification of early-stage tumors—studies show it can reduce the risk of observational error by 20 percent—giving many breast cancer patients an earlier and more effective start in their battle against the disease. The advantage of a mammogram and the new ImageChecker® technology is finding a small breast cancer, which can be treated early, thereby improving the chances of a full recovery.

Current Breast Detection Guidelines

John Muir Health recommends following the ACS guidelines below, and reminds women that early detection is their best protection against breast cancer.

• Breast Self-Awareness—Women should know how their breasts normally feel and report any change promptly to their health care provider. Monthly Breast Self-Examination (BSE) is an option for women starting in their 20s.
• Clinical Breast Examination—Women 20-39 should have a clinical breast exam every three years.
• Mammography Screening—Asymptomatic women age 40 and over should receive a mammogram and clinical breast examination yearly and discuss breast health with their physician yearly.
• Women at increased risk—Those with family history, genetic tendency or past breast cancer should talk with their doctor about the benefits and limitations of starting mammography screening earlier, having additional tests such as breast ultrasound and MRI, or having more frequent exams.

(Posted October 6, 2005)

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