New breast cancer screening guidelines released on Nov. 16 by the U.S. Preventive Services Task Force have created confusion and controversy. These new recommendations, based on studies of demographic data, would have women of average risk of breast cancer wait until age 50 to begin screening mammography and undergo that test every other year until turning 75. The task force said there was not enough evidence to recommend routine screening for women 75 or older.

That compares to the currently accepted standard of beginning at age 40 and undergoing screening annually, as supported by the American Cancer Society, the National Comprehensive Cancer Network (of which Vanderbilt-Ingram Cancer Center is a member), the American College of Radiology and the American Society of Breast Surgeons.

“At Vanderbilt-Ingram Cancer Center, we are committed to the evidence-based practice of medicine, but at the moment, we believe that there is insufficient consensus to warrant a change in established guidelines,”  said Dr. Ingrid Meszoely, clinical director of the Vanderbilt Breast Center, and Dr. John Huff, chief of breast imaging at Vanderbilt, in a statement.

“At this point, our recommendations to women have not changed and remain aligned with American Cancer Society guidelines of annual screening mammography starting at age 40 and continuing for as long as a woman is in good health. We urge women to talk with their health care provider to assess their individual risk for breast cancer and to ask questions about the limitations as well as the benefits of screening mammography.”

A Q&A with Meszoely and Huff follows:

Q – How does age affect a woman’s risk of breast cancer?
A –  Meszoely: As a woman increases in age, her risk of developing breast cancer increases. The probability of being diagnosed with breast cancer from age 40-49 is 1 in 69 whereas from age 60 -69 it is 1 in 27.

Q – How does a woman know if she is at average risk or increased risk of breast cancer?
A -  Meszoely: There are multiple factors that may increase ones risk for developing breast cancer over the “average” risk  individual.  Having family members with breast cancer will increase one’s risk of developing breast cancer, particularly first-degree relatives such as mothers, daughters or sisters. History of radiation to the chest, obesity, alcohol, history of hormone replacement therapy as well as the identification of atypical cells on a breast biopsy are also associated with an increased risk . 

Q – What do scientists mean when they talk about benefits versus harms of mammograms?
A – Meszoely: Benefit refers to identifying a pre-cancer (in situ cancer) or invasive cancer at an early stage when probability of cure is high. “Harms” or risks include additional tests such as additional mammograms, ultrasounds, and MRIs . that require additional time from the patient as well as increased medical costs. Also, significant anxiety may be associated with additional testing. In addition to the above harms, biopsies of benign breast abnormalities may be associated with pain, bruising or infection. Occasionally, a tumor that may have no consequence on an individual’s lifespan may be diagnosed and aggressively treated. However, it is often very difficult to predict a tumor’s behavior at the time of diagnosis.

Q – Why aren’t mammograms recommended for women at average risk of breast cancer who are younger than 40?
A – Meszoely: The risk of breast cancer in “average” risk women under age 40 is less than 1 in 233 or 0.43%.  Given this low risk, the harms of screening in this population outweigh the benefits.

Q – The USPSTF study raised questions about the difference between film and digital mammography. Is digital mammography a superior screening tool and should I be worried if my local screening center doesn’t have digital technology?
A – Huff: Digital mammography has been shown to be more sensitive for the detection of cancer in women with dense breast tissue, including younger women. If a woman has an option between digital and analog mammography, it would be reasonable to choose digital. For women who do not have an option, they should understand that undergoing screening mammography is more important than the specific technology used to perform the examination. A woman should not defer mammography simply because digital equipment is not available.

Q  – Do mammograms need to be done annually or can patients get screened every other year safely?
A – Huff: This is a complex issue. As time between screenings increases, the number of more advanced cancers that “pop up” between screenings naturally increases. This is most important for those cancers that grow rapidly and this is why the standard recommendation has been for annual screenings. If one is to consider increasing the time between screenings, it is probably safest to do in older women who are more likely to develop slower growing tumors. Nevertheless, most authorities continue to recommend annual screening.

Q – When should a patient consider an MRI for breast imaging?
A—Huff: There is good data to support the use of screening MRI in high-risk women. It has been difficult, however, to define the level of risk at which sufficient benefit is reached to justify performance of this test. The American Cancer Society has extensively reviewed the data that is currently available and has recommended annual screening MRI for women with greater than a 20% lifetime risk for developing breast cancer.

Q – What is ductal carcinoma in situ and is it the same as cancer?
A – Meszoely: DCIS is a non-invasive cancer as opposed to an invasive cancer.This suggests that it does not have the ability to invade through tissues such as blood vessels or lymph channels and, therefore, does not have the ability to spread to other parts of the body like invasive cancers. It is often referred to as a pre-cancer and is categorized as Stage 0  in the standard cancer staging system.

Q – Should DCIS lesions always be surgically removed or can a patient and her physician do “watchful waiting”?
A – Meszoely: In general, DCIS should be surgically removed to prevent it from progressing to an invasive cancer.  Surgical removal provides nearly a 100 percent chance of cure. Some DCIS may never progress to invasive cancer but it is often difficult to identify which ones will not change to a true cancer and those that will.  Watchful waiting maybe reserved for very select patients.

Q – Why aren’t all of the cancer organizations recommending breast self-exams?
A – Meszoely: There is no scientific evidence to suggest that self breast exam changes breast cancer death rates. These organizations feel that finding a “lump” on self exam may cause significant anxiety and unnecessary workup of a benign finding.

Contact: The Vanderbilt-Ingram Cancer Center, (615) 936-5847.