In the series of articles on mammography risks we have addressed the main stream approach and conclusions about the early detection of breast cancer with yearly mammograms in women over 50 years old. We have also looked at the research that indicates the x-rays used for mammograms may add to the risk of developing breast cancer.

So we have concerns about the cumulative effect of the x-ray exposure from mammograms on our breasts. Yet we don’t want to be foolish and let an early more treatable breast cancer go undetected.

What’s a gal supposed to do in this dilemma?

Let’s take a look at thermography as another modality for detecting breast cancer.

As a cancer begins to grow it develops its own blood supply that grows at a rapid rate. In fact even in the pre-malignant state, the new blood supply begins to grow at an accelerated rate.

An increased heat pattern develops in the areas of these abnormal blood vessels. A procedure called thermography detects this abnormal heat pattern by scanning the breasts with a specialized infrared camera. Then high tech computer programs analyze these thermograms. Doctors skilled and board certified in thermography analyze the results of these procedures to detect abnormal heat patterns.

Thermography can detect the earliest signs of a pre-malignant or malignant cancer developing in the breast.

Here’s what two doctors board certified in thermography have to say about it:

 “An unprecedented level of early detection can be realized when thermography is added to a woman’s regular breast health care. It has been found that an abnormal thermographic image is the single most important sign of high risk for developing breast cancer, 10 times more significant than a first order family history of the disease. Studies show that this technology has the ability to warn a woman that a cancer may be forming up to 10 years before any other test can detect it. This gives breast thermography not only the ability to detect cancer at its earliest and most treatable stage, but to also act as a biological marker warning a woman about her own unique level of future risk for breast cancer.

Women who undergo the test find it to be fairly uneventful, since the procedure uses no radiation or contact with the breasts. Women with dense breasts, implants, and women who are pregnant or nursing can be imaged without any harm or reduction in the accuracy of the test.

Currently, no single screening procedure can detect 100% of all breast cancers. Thermography is designed to be used with mammography and not as a replacement. Studies show that when thermography is added to a woman’s regular breast health checkups (physical examination + mammography + thermography), 95% of all early stage cancers will be detected. This would give the vast majority of women who are diagnosed with this disease the reality of returning to a normal healthy life.

Should we continue to concentrate our efforts on procedures that can only detect an existing cancer, or should we be focusing on true screening methods that can warn of a pending problem far in advance? The number of women who die from this disease will continue relatively unchanged if nothing is done to provide them with a true early warning system.

Breast thermography has the unique ability to warn most women far enough in advance to give them a fighting chance. Combined with its ability to play a role in primary prevention, the life saving implications are incredible. The addition of this technology to every woman’s breast health care will make the greatest impact on breast cancer mortality. With breast thermography, women of all ages are given hope and a true early detection edge in the battle against breast cancer.”

References:

Beating Breast Cancer

William Hobbins, MD, FABS, DABCT, FIACT

William Amalu, DC, DABCT, DIACT, FIACT

About the authors:

William Hobbins, MD, a Fellow of the American Board of Surgeons and a board certified clinical thermologist, has been performing thermographic breast imaging for over 35 years. As an internationally recognized authority in this field, he has sat on multiple medical and thermographic boards, authored numerous articles, and has contributed a significant amount of research to the medical database using this technology. He currently practices in Madison Wisconsin and can be contacted at 608-273-4274.

William Amalu, DC, a Fellow of the International Academy of Clinical Thermology and a board certified clinical thermologist, has utilized thermography in practice for over 14 years. He is currently the President of the International Academy of Clinical Thermology and practices in Redwood City California. He can be contacted at 650-361-8908 (www.breastthermography.com).

Blessings,

Dr. Jo

 We covered the main stream reasoning and thinking in the previous blog posts which you may review here: 

• Part 1
• Part 2
• Part 3
• Part 4

In this issue we will look at two research experiments that pose a different perspective. 

First let’s look at a study done by the Radiation Biophysics Group, School of Physics and Astronomy, The University of Birmingham, Birmingham B15 2TT, United Kingdom. 

This group exposed three different sets of human skin fibroblast cells to three types of radiation and then checked the cells to see if they became cancerous.

Using isolated cells in a study is called “in vitro”, meaning this testing was not performed on a person, but rather in a test tube or plate. 

These are the types of radiation that they used:

                High energy source simulation:

                1. Quality of radiation that the atomic bomb survivors were exposed to.

                2. 2.2 MeV electrons from a strontium-90/yttrium-90 (90Sr/90Y) radioactive source.

Both of these types of radiation produced the same amount of cancer in the isolated human skin fibroblasts. 

                Mammography source:

                3. 29 kVp X rays which are used for mammography screening 

When they analyzed their data they made this observation: 

“The increased potential of low-energy X rays to induce neoplastic (cancerous) transformation is clearly seen. Mammography X rays are 4.4 plus or minus 2.0 (SE) times more effective at inducing neoplastic transformations of CGL1 cells in vitro than high-energy electrons for low absorbed doses.” 

“This suggests that the risks associated with mammography screening may be approximately five times higher than previously assumed and that the risk–benefit relationship of mammography exposures may need to be re-examined.” 

Of course, this type of research cannot be performed on women and we don’t know for sure how to interpret this kind of in vitro testing with what actually occurs in the human body with its repair mechanisms. 

However, it does give us some information to ponder.

This second research project gets even more interesting.

At the Lawrence Berkeley National Laboratory (Berkeley Lab) cell biologist Mary Helen Barcellos-Hoff transplanted a special line of nonmalignant breast cells that had not been irradiated into mammary glands that had been exposed to x-rays. Nevertheless almost 75 percent of the transplanted cells developed tumors. 

Did you get that? Cells that had not been exposed to any x-rays became cancerous when they were placed in an environment of breast glands that had been x-rayed. 

For a control group Barcellos-Hoff transplanted the same type of cells into nonirradiated mice breast tissue. Only 20% of those cells became cancerous. 

So what does this mean? Somehow the environment surrounding a cell has an effect on whether the cell becomes cancerous. In other words something besides genetic mutations (changes in DNA) can induce cancer in cells. 

A network of fibrous and globular proteins (called the extracellular matrix (ECM), surrounds each breast cell. This tissue surrounding the cell sends signals to the cell. Proper communications between the cell and its microenvironment are essential for normal functioning. 

“Ionizing radiation is like a wound, in that it produces a defensive response from the affected tissue. Usually this helps to protect undamaged cells and eliminates those that have become abnormal,” Barcellos-Hoff says. “However, if there is too much damage, the defense response can become a problem.” 

As an example of this defense response, consider what happens to the skin when exposed to sunlight. Just the right amount of exposure stimulates the skin to produce more melanin which helps to prevent skin damage when exposed to sunlight in the future. 

But if someone stays out in the sun too long, the skin gets burned and damaged. 

When breast tissue is exposed to low doses of radiation the surrounding tissue signals the cells to prevent damage to the DNA. If the radiation exposure goes higher, the cells get the wrong message which then can allow mutations and cancer to develop. 

In an on-going study Barcellos-Hoff and her team have preliminary evidence that human breast cells exposed to radiation have difficulty communicating between the tissue and cell. This abnormal activity is typical of cancer cells.

So these two studies increase our distrust of mammograms. 

Is there an alternative way to detect breast cancer in its early stages that doesn’t carry risks of actually causing breast cancer? 

We will address that question in the next blog. So stay tuned. 

Blessings,

Dr. Jo 

P.S. Sorry that these articles on mammography have been a bit technical. I felt that you needed to know the technical parts so you could make the best informed decisions for yourself. 

References:

RADIATION RESEARCH 162, 120–127 (2004)

0033-7587/04 $15.00

q 2004 by Radiation Research Society.

All rights of reproduction in any form reserved

NEW FINDINGS ON BREAST CANCER REPORTED AT AAAS

Lynn Yarris, (510)486-5375, lcyarris@lbl.gov

• Part 1
• Part 2
• Part 3

And here we are for Dr. Boyce’s conclusions on whether or not the risk of mammograms adding to the development of breast cancer outweigh the benefits.

“Does x-ray mammography put women at an even higher risk of developing a radiation induced breast cancer?

The controversy today surrounding screening of healthy women is not whether the radiation exposures are hazardous, but whether young women, under the age of 50, benefit from mammograms.

A 30 percent reduction in death from breast cancer has been convincingly demonstrated in randomized trials of women over the age of 50. The benefit for younger women is less clear, but apparently lower. The possible hazard from mammography x-rays is very low and should not be a factor in individual decisions to undergo this procedure.

The same is true for most diagnostic x-ray procedures. Nonetheless, unnecessary radiation exposures should be avoided and continued vigilance is required to ensure that the benefits associated with specific procedures outweigh the future risks.

When the mammography is performed because of symptoms that may be cancerous or because risk factors place a woman at especially high risk of breast cancer, such as known genetic conditions or prior high dose radiation to the chest, the benefit from the low dose radiation procedure substantially outweighs the possible future risk.

And if you are over the age of 50, the risk benefit equation is clearly in your favor since radiation exposures at these ages are thought to have little connection to increases in breast cancer later in life.

In other words, the small presumed risk is more than offset by the benefit of the procedure, and this is especially true for women at high risk for breast cancer.

Should women be concerned about the radiation they receive when having periodic mammography x-rays or other procedures involving chest irradiation?

As stated earlier, cancer risk is related to age at the time of radiation exposure and the dose of radiation received. A mammography x-ray might result in a breast tissue dose of about 0.3 cGy. If a woman received 10 mammograms as a young woman, the total dose would be about 3 cGy.

What is the risk associated with such exposure?

 Keeping in mind that epidemiologic studies have not detected statistically significant increases below a dose of about 20 cGy, we do know that 100 cGy increases risk by about 40%. One can estimate that the 3 cGy from periodic mammography screenings would increase your risk by about 1.2% or a relative risk of 1.012. Such low risks are not detectable in human studies.

Nonetheless, all unnecessary radiation should be avoided and although the presumed risk is very small, it should be clear that the benefit from the medical exposure would far outweigh it. Decisions to have diagnostic procedures because of medical symptoms, however, should not be delayed because of the concern over presumed radiation risk.

Conclusions

Women with clinical symptoms of a serious disease should not refuse an x-ray diagnostic procedure because of possible radiation risk (the risk associated with these procedures is very low and the immediate benefit may be great).

Most women who received radiation exposures in the past will not develop a radiation-related breast cancer.”

Dr. Jo’s comments:

Dr. Boyce brings out some important facts as known through the various studies that he presented. Perhaps those of us over 50 can feel more assurance that we won’t live long enough for the radiation effects of mammography to trigger cancer in our breasts. And having the mammograms performed may detect early and more treatable cancer that would be life saving or prolonging.

That’s the main stream medical perception of mammograms.

But I know many of you pursue the very healthiest practices for your bodies and continue to be skeptical about the risks of mammography and I tend to side with you.

So in the next series of articles we will look at another perspective and review alternative and perhaps healthier, less risky ways to diagnose breast cancer in its early stages.

Blessings,

Dr. Jo

* John D Boyce, Jr, DSC, Scientific Director,
International Epidemiology Institute, Rockville, MD 20850

When reproducing this material, credit the authors and the Program on Breast Cancer and Environmental Risk Factors in New York State.

Copyright Statement: Print and electronic publications of the Cornell Program on Breast Cancer and Environmental Risk Factors (BCERF) are copyrighted by Cornell University ©2004. We encourage the use of BCERF materials and publications, including text, tables, diagrams, pictures or other graphics with the following stipulations: 1) use is for educational purposes only, and 2) credit is given to BCERF and original authors, illustrators and photographers.
Reproduction or distribution in whole or in part of any BCERF print, graphic or electronic material for commercial use is strictly prohibited. Any other use, reproduction or distribution is forbidden without the written consent of the original author.

 In this article *Dr. Boyce presents more information about the risks of developing breast cancer and comes to his conclusions at the end.

 From Dr. Boyce’s article:

“Common conditions or life style factors that increase a woman’s risk of breast cancer by about 40%:

• Never being pregnant or not having children (nulliparity)
• A very early age at first menstrual period (under age 11 years at menarche)
• A very late age at menopause.

Even higher risks are associated with:

• Family history of breast cancer, namely, having several first degree relatives with breast cancer,
• Possessing a damaged or mutated “breast cancer” gene such as BRCA1
• A prior history of breast cancer (developing a second breast cancer is related in part to the same factors associated with developing the initial cancer).

Is it true that while ionizing radiation can definitely cause breast cancer, it is not a major source of breast cancer cases?

Yes. It has been estimated that less than one percent of all breast cancer cases might be attributed to ionizing radiation. Since most of this radiation comes from natural sources, which we have little control over, and from medical sources, which are for our benefit, there are few opportunities to reduce exposure and thus reduce risk.

It should be noted though, that a few groups of women are at high risk of radiation-induced breast cancer for whom surveillance for early detection should be considered.

What groups of women are at especially high risk of developing radiation-induced breast cancer?

• Highest risk: children who received radiation treatments for malignant and nonmalignant conditions.
• Up to 50% of young girls treated for Hodgkin’s disease in the past with very high radiation doses may develop breast cancer in later life.
• Infants treated for enlarged thymus glands.
• Children treated for various forms of cancer.
• Women irradiated for benign breast conditions, including breast inflammation after giving birth.

 Most of these types of radiation treatments for non-malignant conditions are no longer given. During treatments for cancer medical oncologists continue to strive to reduce radiation exposures to all healthy tissue, including the breast.

What should a woman do if she received radiation treatments to the chest as a young woman?

Women exposed to high levels of radiation in the past (e.g., radiotherapy to the chest for non-malignant or malignant conditions), should make sure they bring this information to the attention of their health care provider. Together they can then decide upon a medical strategy that might include periodic breast examinations, including mammography or other appropriate breast imaging procedures, to detect any problems early so that treatment might be more effective.”

In the fourth part of this series on mammography we will come to the main stream conclusions about the risks of mammography in regard to the development of breast cancer. From there we will start looking at some alternatives to mammography.

So stay tuned,

Dr. Jo

* John D Boyce, Jr, DSC, Scientific Director,
International Epidemiology Institute, Rockville, MD 20850

When reproducing this material, credit the authors and the Program on Breast Cancer and Environmental Risk Factors in New York State.

Copyright Statement: Print and electronic publications of the Cornell Program on Breast Cancer and Environmental Risk Factors (BCERF) are copyrighted by Cornell University ©2004. We encourage the use of BCERF materials and publications, including text, tables, diagrams, pictures or other graphics with the following stipulations: 1) use is for educational purposes only, and 2) credit is given to BCERF and original authors, illustrators and photographers.
Reproduction or distribution in whole or in part of any BCERF print, graphic or electronic material for commercial use is strictly prohibited. Any other use, reproduction or distribution is forbidden without the written consent of the original author.

http://envirocancer.cornell.edu/factsheet/physical/fs52.radiation.cfm#mammog

In summary, ionizing radiation exposure comes from medical x-rays and radioactive substances. They are powerful enough to knock an electron off an atom and may cause changes in a cell’s DNA which can lead to cancer.

On the other hand non-ionizing radiation cannot knock an electron off of an atom and does not directly damage DNA. Non-ionizing radiation comes from microwave appliances, power lines, cell phones, radio and television waves and radar.

With that in mind let’s continue to explore our question:

Does the radiation exposure from the mammography x-rays contribute to the development of breast cancer?

Here’s Dr. Boyce’s introductory paragraph:

“Everyone is exposed to ionizing radiation from natural and medical sources. In fact, ionizing radiation may be the most studied cancer causing agent in humans with scientific committees on radiation continuously reviewing and evaluating adverse health outcomes for over 70 years. The female breast is known to be highly susceptible to the cancer-causing effects of radiation when exposure occurs before menopause. This fact sheet will discuss what is known about radiation induced breast cancer and what factors influence or modify the effects of exposure. Most people are not exposed to the high levels of radiation that are known to cause breast cancer, and accordingly, radiation is not considered a major cause of breast cancer. Although unnecessary exposures should be avoided, diagnostic or therapeutic procedures should not be refused because of possible radiation risk.”

Here are his points to substantiate that introduction:

Is ionizing radiation a cause of breast cancer?

Yes in women exposed to high doses of radiation such as:

• the female survivors of the atomic bombings in Japan during World War II
• women given radiation therapy to treat Hodgkin’s disease and both malignant and benign breast disease
• girls treated as infants or children for several non-malignant conditions such as enlarged thymus glands
• young adolescents and women who received large numbers of diagnostic x-ray examinations to monitor tuberculosis treatments or to monitor the curvature of the spine during treatment for severe scoliosis.

What have all these studies shown about radiation-induced breast cancer?

1. Female breast tissue is highly susceptible to radiation effects
2. It takes a minimum of about 5-10 years for a radiation-induced breast cancer to develop
3. Greater levels of radiation exposure lead to greater risk of breast cancer, i.e., there is a direct dose and effect relationship
4. A woman’s age at the time of exposure is also very important.

What are the important characteristics of radiation-induced breast cancer?

First, the breast tissue of young women is one of the most sensitive tissues to the carcinogenic action of ionizing radiation.

Second, it takes a minimum of about 5-10 years after exposure before a radiation-induced breast cancer would develop, and usually many more years.

Third, no matter how low the dose, there is some small risk associated with the exposure. Fortunately, for a very small exposure, the risk is essentially negligible and would not be related to detectable increases in breast cancer risk even if millions of women were studied. Nonetheless, it is important to minimize all unnecessary radiation exposure.

Fourth, age at exposure is one of the most important determinants of the future risk of developing breast cancer due to radiation later in life. Young girls are at highest risk and women irradiated around the menopausal ages are at low risk. In fact, for exposure after the age of about 45 years there is little evidence that radiation increases the occurrence of breast cancer.

Why might this be so?

One theory is that for radiation damage of breast tissue to develop into a cancer, there is the need for estrogen stimulation and tissue proliferation that occurs during monthly menstrual cycles. Once the menopausal ages have been reached, there is a decrease in this tissue proliferation and damaged cells fail to develop into cancers.

Conversely, when a young girl is exposed to radiation, she will have menstrual cycles for several decades that might enhance the development of any underlying damage caused by the radiation. There is evidence to suggest that exposure to the immature breast during early development, and around the age of beginning menstruation, carries a higher risk than at other times of a woman’s life.

Fifth, the vast majority of persons exposed to radiation do not develop a cancer related to this exposure. Even among the nearly 25,000 female atomic bomb survivors in Japan who have now been followed for over 50 years, only 173 breast cancer deaths occurred and only 41 (or 24 percent) were attributed to the radiation received in 1945.

If it does, should I have a mammogram every year to check for breast cancer?

Those are tough but important questions.

So let’s take an in-depth look at the scientific considerations. Then you must decide your course of action for yourself.

John D Boyce, Jr, DSC, Scientific Director, International Epidemiology Institute, Rockville, MD 20850 wrote a comprehensive article titled Ionizing Radiation and Breast Cancer Risk. You may access the full article on the Cornell University web site at:

http://envirocancer.cornell.edu/factsheet/physical/fs52.radiation.cfm#mammog

Over the next few newsletters we will look at the highlights from that article and some newly released research findings.

We will also look at the question:

Is there a reliable alternative for early detection of breast cancer that does not use ionizing radiation?

Dr. Boyce points out the difference between ionizing radiation and non-ionizing radiation, an important distinction when considering the effects of exposure to radiation.

“What is ionizing radiation?

Radiation is the emission of energy in the form of waves or particles. Radiation that is so powerful that it can remove electrons from atoms is called ionizing. Examples of types of ionizing radiation are x-rays from medical machines and gamma rays from radioactive substances.

How does exposure to “non-ionizing” radiation, such as from microwave ovens, affect breast cancer risk?

Non-ionizing radiations do not possess enough energy to remove electrons from atoms. Examples of non-ionizing radiation are the electromagnetic fields from electrical power lines, radio and television waves, radar, cellular telephones and microwave ovens. The mode of interaction of non-ionizing radiation with the body is much different from the way ionizing radiation interacts. Most importantly, ionizing radiation can directly damage DNA and cellular molecules whereas non-ionizing radiation cannot.

The concern over non-ionizing radiation is related to the heating effects of this type of radiation. Exposure standards are set to keep exposures well below the level that might shock or heat tissue to an unacceptable level. They are thus set to reduce the occurrence of rapidly occurring effects and not effects which require long periods of time to develop such as cancer. While there is overwhelming evidence from human investigations, animal experiments and cellular studies proving that ionizing radiation is a cause of cancer, there is no such evidence for the non-ionizing radiations. There is a world of difference between the radiation from an x-ray machine and the non-ionizing electromagnetic fields from say an electric blanket, and care should be taken not to confuse the two.

How do people get exposed to radiation?

We live in a sea of low-level radiation from natural sources. These natural sources include radioactive radon gas that we breathe, radioactive elements such as potassium-40 that is found in many foods (including salt), uranium and thorium which are found in soils and building materials, and cosmic rays that continually bombard us from outer space.

However, there are other sources of manmade ionizing radiation. These sources include medical x-rays which are used to both diagnose disease and to treat cancer; occupational radiation which is experienced during employment in certain industries and professions; radioactive fallout from nuclear weapons testing or reactor accidents; and radioactive emissions from the normal operation of nuclear facilities such as those used to produce electrical power.

In terms of exposure to the entire population, natural sources contribute by far the largest radiation dose to people, with medical radiation contributing the next largest amount. For individual women the amount of radiation experienced throughout life is influenced by her access to medical care, illnesses requiring diagnosis or treatment, residence that is related to levels of background radiation, and occupation in a profession with possible radiation exposure.

As you read through this series of articles over the next few weeks keep in mind this distinction between ionizing and non-ionizing radiation.

Now don’t start worrying your head off about whether or not to have mammograms done. Be patient and review all of the information in the subsequent articles, then make an informed decision.

Blessings,

Dr. Jo