Breast Cancer screening: the goal is early detection
To screen for breast cancer or not?
When you consider that 1 in 8 women in the U.S. will be diagnosed with breast cancer during her lifetime, the answer to this question should be “yes.” The more difficult question to answer is, “What is optimal breast cancer screening?”
Before discussing specific breast cancer screening strategies, it is essential to review some important facts about breast cancer. First, breast cancer is not preventable, although some risk reduction strategies may be offered to individuals who are at high-risk for breast cancer. Second, the two most significant risk factors for breast cancer include being female and increasing age. Women in the U.S. have an average lifetime risk of 12% for being diagnosed with breast cancer. Breast cancer can occur in males, but it represents only 1% of all breast cancer diagnoses in this country each year. Third, although having a strong family history of breast cancer (and other related cancers such as colorectal, ovarian, pancreatic and prostate) can potentially make you more genetically susceptible to developing breast cancer, it is absolutely essential to understand that having a family history negative for breast and breast-related cancers does not mean that your risk for breast cancer is minimal. Ninety percent of all breast cancers are diagnosed in women with negative family histories.
With the goal of detecting breast cancer at its earliest possible stage, there have been three methods commonly recommended for optimal breast cancer screening. These methods include breast self-examination, clinical breast examination and mammography. Each of these methods has strengths and limitations.
Breast self-examination consists of a woman examining her breasts every one to two months. There are specific techniques for examination of the breasts that are more effective when compared to others. Check with your primary care provider, gynecologist, breast clinic or health department for educational materials that illustrate these techniques.
When a woman examines her breasts regularly, she develops the most accurate appreciation of what is new or changed in her breasts. This practice is particularly important for women who have very dense breast tissue with diffuse nodularity (“lumpiness”) because clinical breast examination and mammography are more limited for this patient compared to a woman whose breasts contain primarily fatty tissue.
There are three things to keep in mind when performing breast self-examinations. First, most of the changes that a woman finds in her breast will not be cancer. Breasts, like all other areas of the body, change with time due to major physiologic events (puberty, pregnancy, menopause) as well as to more minor short-term fluctuations in hormones (menstrual cycle, dietary and exercise, and exogenous hormones such as birth control and hormone replacement therapy). Change is inevitable, with many newly discovered breast findings disappearing within one to three menstrual cycles in a premenopausal or perimenopausal woman. Although benign changes occur in postmenopausal women, new dominant findings such as a mass or nipple discharge warrant immediate investigation.
New or suspicious breast findings discovered by routine breast self-examination deserve further evaluation. In most cases, this work-up includes a clinical breast examination and breast imaging (mammography and breast ultrasound). Most of these findings will only require further observation. However, occasionally, the discovery may be suspicious enough to necessitate a biopsy. These biopsies usually involve an ultrasound or mammographically-guided core needle biopsy. Many of these biopsies will also be found to be benign.
There are some very vocal critics of breast self-examination. They actively discourage women from performing routine examinations of their breasts for two primary reasons. First, there is the concern that such vigilance causes unnecessary anxiety for many women, especially if the woman has dense nodular breasts that are difficult to evaluate. Significant anxiety and fear of cancer may also occur if the woman does find something new. In reality, it becomes more comfortable and less intimidating for these women as they examine themselves each month and become more familiar with their unique anatomical features. Second, as noted above, most of the findings that women discover on their own will require additional clinic visits and testing, with a significant number of biopsies also being performed. Since most of these findings will ultimately lead to a benign diagnosis, critics argue that breast self-examination leads to unnecessary costs as well as unnecessary risks to the women who undergo negative biopsies. Such concerns for patient safety and the financial burden should be a priority, but one must always step back and look at the bigger picture. Although most new or suspicious breast findings discovered by self-examination are benign, 60% of all breast cancers are initially identified by women on a routine or incidental breast self-examination.
The second method used for breast cancer screening and detection is the clinical breast examination. It is also vital, and it should be performed by your primary care provider or gynecologist each year, typically as part of your annual wellness check-up. Approximately 15% of all breast cancers are initially discovered by clinical breast examination.
And finally, the third method used for breast cancer screening and detection is mammography. The 3D mammography machines here in Washington represent some of the best technology currently available. The technicians who perform the mammograms are outstanding, and the radiologists who interpret these studies have specialized expertise in breast imaging. There are also programs available to help women get mammograms if they don’t have the financial means. It has been my experience that very few women are not aware of the importance of getting mammograms for the detection of breast cancer. For most women, the first mammograms should be performed at 40 years of age. Although there has been significant disagreement among various health and medical organizations about the frequency of subsequent mammographic screenings, my recommendation is to have your mammograms performed every year after that. Some organizations have also recommended that women stop getting mammograms when they reach a certain age, but when you consider that the risk of breast cancer increases as you get older this strategy doesn’t make any sense to me if your primary objective is to detect breast cancers in all women at the earliest possible stage.
Unfortunately, there also many misconceptions regarding the limitations of mammography. First, most breast cancers are not initially detected by mammography. Approximately 25% of all breast cancers are first discovered by mammography. Remember that 60% of all breast cancers are initially found by the woman on self-examination. As more women include routine breast self-examination and annual clinical breast examination, along with yearly mammography, in their overall breast cancer screening strategy, these statistics will change. We will see more breast cancers that are initially discovered by mammography because these cancers will be too small to detect on self-examination. Second, I have also known patients who overestimated mammography’s ability to detect breast cancer. They relied on mammography as their sole method for screening, and although most of these women were very vigilant about getting their yearly mammograms, they disregarded self-examination and clinical breast examination and unfortunately many of these women presented with large advanced breast cancers even though they may have had a “negative” mammogram just a month or two before. How could this be? Approximately 20-25% of breast cancers cannot be seen on mammograms. This situation may be due to breast density or the specific type of breast cancer.
The debate regarding optimal breast cancer screening strategies will continue. However, the primary objective will not change — to detect breast cancers as early as possible. By identifying more early-stage breast cancers, more women will be able to save their breasts, avoid chemotherapy, return to their normal lives sooner and, most importantly, join the sisterhood of strong and courageous breast cancer survivors.
Dr. Daniel Richardson, of Vidant Breast Clinic, 612 E. 12th St., Washington, can be reached by calling 252-946-0181.