Screening for Breast Cancer

Dispelling myths about mammography

/ Author:  / Reviewed by: Joseph V. Madia, MD

In celebration of Breast Cancer Awareness month, dailyRx spoke with one of the nation's leading experts in the area of breast cancer screenings.

Daniel B. Kopans, MD, is professor of radiology at Harvard Medical School and senior radiologist at the Avon Comprehensive Breast Evaluation Center at Massachusetts General Hospital.

We asked Dr. Kopans to explain the latest recommendations, dispel myths about breast cancer screenings and tell you what you need to know to proactively manage your breast health.

Question: There has been a great deal of confusion about breast cancer screenings. What are the latest recommendations for a woman who has no personal or family history of the disease?

Dr. Kopans: Anyone can make recommendations. The U.S. Preventive Services Task Force caused all the confusion, and there was only one person on that panel who had any expertise with breast cancer. There were no surgeons, no oncologists, and no radiologists on the panel. There was no one who directly provided care for women with breast cancer.

The guidelines that are supported by the data are the American Cancer Society Guidelines (as well as the American College of Radiology and the American College of Obsterticians and Gynecologists: Annual mammography for all women beginning at the age of 40.

Question: If a woman does have a family history of breast cancer, what is suggested in terms of genetic testing and screenings?

Dr. Kopans: It is important to realize that 75 percent of women who are diagnosed with breast cancer each year are NOT at increased risk, and DO NOT have a family history. All women are at risk.

Approximately, 10 percent of women diagnosed with breast cancer each year have a genetic predisposition. For women who have a possible genetic risk (father, mother, sister, or daughter diagnosed with breast cancer or multiple relatives), they should consult a genetic counselor. The American Cancer Society and the American College of Radiology recommend that these women begin mammography at a younger age and may benefit from Magnetic Resonance Imaging screening alternating with mammography (see next question).

Question: When is MRI screening recommended?

Dr. Kopans: MRI screening can find cancers that are not detected by mammography. The problem is that we do not know if finding these cancers saves lives (there are some cancers that will never kill, and there are some cancers that, even finding them earlier, does not save the woman's life).

Mammography is the only test that has been shown by the most rigorous scientific study, the randomized, controlled trial (RCT), to reduce deaths from breast cancer. It is important to know that there has never been a randomized, controlled trial of MRI screening to know whether or not screening using MRI will save lives. Nevertheless, for women who have a genetic mutation, their risk is so high (50-80% lifetime risk of developing breast cancer), MRI is suggested because the only viable alternative is to have their breasts removed by prophylactic surgery:

Question: If a woman has had breast cancer, what are the recommendations for her?

Dr. Kopans: These women should all have annual mammography and clinical breast examination determined by their surgeon and/or oncologist.

Question: There is concern about the amount of radiation that typical mammography emits. What do you tell your patients about this?

Dr. Kopans: The data clearly show that the breast is susceptible to radiation while it is developing, in girls and teenage women. By the time a woman reaches the age of 40, the breast is likely not affected by radiation. There is no direct evidence of any radiation risk to the breast. Even the estimated risk is so low, that it is outweighed by an even 5 percent decrease in breast cancer deaths due to mammograms.
Although it is not proof, hundreds of millions of women have been having mammograms since the mid 1980's. If mammography was causing breast cancers the incidence of breast cancer would be going up. Instead it has been decreasing since 1999.

Question: There is also concern that the pressure of mammography could actually spread any cancer that exists. True?

Dr. Kopans: There is, absolutely, no data to support this myth. When mammography screening begins, the death rate from breast cancer goes down. The myth was supported by scientific nonsense, promulgated by individuals who took unrelated pieces of information and linked them together to mislead everyone. Mammography is extremely safe.

Question: Some women are convinced that thermography is a better, safer screening method. How do you respond?

Dr. Kopans: There are no data to support the use of thermography. The fundamental problem is that thermography measures skin temperature. Even if a breast cancer causes increased heat, it has to reach the skin for the thermogram to detect it. If a house is well insulated a thermogram of the oustide cannot detect a roaring fire inthe fireplace. Similarly, the breast is an excellent insulator and blood rapidly dissipates any heat.

Thermography was shown to be ineffectual years ago. Unfortunately, since it was FDA approved before the FDA required proof of safety and efficacy, it has been "grandfathered" in with FDA "approval", so companies keep bringing it up to take advantage of FDA apporval. Thermography cannot find cancers at the small size needed for cure.

Question: What are other common myths about breast cancer screenings that you'd like to dispel?

Dr. Kopans: The major myth is the use of the age of 50 as a threshold for screening. There are NO, NONE, ZERO data that show that any of the parameters of screening (recall rates, biopsy rates and cancer detection rates) change abruptly at the age of 50 or any other age. There are no data that show that these parameters change at menopause (the age of 50 was originally chosen as a surrogate for menopause).

The myth developed as a result of scientifically unsupportable analyses and data manipulation to make the age of 50 appear as a legitimate threshold when there are no data to support this. Anyone who still argues that the age of 50 is a biologically or scientifically legitimate threshold for screening is either uninformed, or lying. (I'm sorry, but this is not rocket science - there are no data to support its use and "experts" should stop promoting it).

The reason that the age of 40 is a threshold is that most agree that the only way to prove a benefit from screening is through the use of randomized, controlled trials, and these trials did not include women younger than age 39.

Question: Talk about the role of ultrasound as a companion or follow-up screening.

Dr. Kopans: Ultrasound is like MRI. It can find some cancers that are not evident by mammography, but we do not know the importance of these cancers, and we do not know if screening with ultrasound saves lives. Furthermore, ultrasound results in 2-3 times as many false alarms as mammography, and mammography is always under fire for false alarms.

Question: Do specific types of mammography, i.e. Tomosynthesis, provide superior imaging technologies and should women seek these?

Dr. Kopans: Digital Breast Tomosynthesis (DBT) is an improved mammogram. Conventional two dimensional mammograms (film/screen and digital) are like looking at a book with clear pages. You can hold the book up and see all the words, but they are superimposed making it difficult to read. DBT allows the radiologist to look at each individual page so that cancers are seen more clearly, and there are fewer false alarms.

Question: Are there any recommendations for men to undergo breast cancer screenings?

Dr. Kopans: Approximately 1000-2000 men are diagnosed each year with breast cancer (vs. 200,000+ women). Men from families with genetic mutations should discuss screening with genetic counselors.

Question: What's most important for our visitors to know about breast cancer screenings? What would you like them to take away from this article?

Dr. Kopans: There is a huge amount of misinformation that has been spread over the past decades. Mammography screening is one of the major medical achievements of the past half century.

  • From 1940-1990, the death rate from breast cancer was unchanged despite the introduction of new therapies.
  • Mammography screening began in the mid 1980's, and, as expected, the death rate began to decline in 1990.
  • The death rate has now decreased by more than 30%.

This is not a triumph over these cancers, but a huge improvement on which we need to build. Improved therapies only save lives when breast cancers are found early. Opponents should end the nonsensical attacks on mammography so that we can concentrate on further reducing the death rate from these cancers.

Dr. Kopans is a member of the American College of Radiology (ACR) Breast Imaging Commission
 

Review Date: 
October 11, 2011