If you didn’t see it, the results of the Canadian National Breast Cancer Screening Study were published in the British Medical Journal on Feb 10, 2014. This important study of almost 90,000 women ages 40-59 from across Canada revealed that the number of women who died from breast cancer was the same whether women received screening mammograms annually for 5 years or had annual physical breast exams alone. During the five-year screening period, 666 invasive breast cancers were diagnosed in the women who were screened using mammography, while 524 were found in those receiving physical breast exams. Both groups received the usual medical treatment for breast cancer. Out of all of these women, 180 in the screening mammogram group and 171 of the women in the physical exam group died of breast cancer during the 25 year follow-up period. The conclusion – early detection through mammography did not reduce deaths due to breast cancer.
Dr. Kaur’s Guidelines for Screening
1. Women over 20 years of age should practice monthly breast self-exams
2. All women over 20 years of age and especially women with a family history of breast cancer should have an annual clinical breast exam
3. If you are over 20 and under 50, have an annual screening thermogram. Use mammogram, ultrasound, MRI and/or biopsy to explore any irregular thermogram results
4. If you: a) have a strong family history of breast cancer; b) have been on the birth control pill or hormone replacement therapy for over 5 years; c) or have other increased risk factors – have an annual thermogram, ultrasound, MRI and clinical breast exam. Use mammography when necessary to confirm a diagnosis or if there is a lump.
5. If you are over 50, have an annual thermogram, clinical breast exam and use mammography, ultrasound, MRI and biopsy as needed if you discover a lump
Common Breast Screening Techniques
If you should require breast screening for a palpable lump or because of a family history, this overview informs you of the risks and benefits of each technique.
Thermography measures subtle changes in the temperature at the surface of the body, using an infrared camera that detects the infrared heat energy emitted from the skin. Because cancerous tumours have an increased blood supply, they are slightly hotter than the surrounding areas in which they are found. This difference in temperature is measurable, particularly when both breasts can be compared.
An area of increased heat can then be investigated further with a mammogram, ultrasound or MRI. Thermography measures physiology, unlike a mammogram, which detects changes in anatomy. Often the physiological changes precede the anatomical changes. Thermograms may be able to detect abnormalities in breast tissue up to 10 years before a mass is detected by mammography.[i] A 1980 study found that 38% of patients with abnormal infrared images were diagnosed with breast cancer within four years.[ii]
Canadian studies done at the Ville Marie Breast Center in Montreal have found that thermograms were positive for 83 percent of breast cancers compared to 61 percent for clinical breast exam alone and 84 percent for mammography. The 84 percent sensitivity of mammography was increased to 95 percent when infrared thermographic imaging was added.[iii]
Thermograms are particularly useful for women with denser breasts for whom mammography is ineffective, and for women under 50 years of age. In these women, thermograms can signal an abnormality that may not be detected by mammography or clinical breast exams.
Limitations and Risks of Thermography:
- Since thermography does not rely on radiation exposure or compression of the breast, there are no risks associated with it
- As thermography is a thermal representation of the skin, it is unable to pinpoint precisely at what depth a cancerous tumour may occur
- If a cancerous tumour exists that is not exhibiting excess heat or an increased blood supply, thermography may not detect it
- Thermograms are not as effective in detecting micro-calcifications as mammography is
- Thermograms may signal a problem in the breast that cannot be detected using other tests – this is known as a “false positive”. However, this may also mean that it is simply too early to verify that cancer is present using other means. It is a good early warning screening tool to help women become proactive about taking care of their breasts.
A mammogram is an x-ray of the breast that can pick up lesions as small as .5 centimetre, which you are usually not able to feel. Mammography can detect approximately 85 percent of all breast cancers while an experienced physician can detect 61-92 percent of breast cancers through a breast exam, depending upon the physician. If a woman has dense breasts, a lump may not be visible through the tissue and mammograms will miss up to 25 percent of tumours in women 40-49 years old.
Mammograms are less accurate in picking up lesions in smaller breasts, and they expose us to doses of radiation that are cumulative and over time can increase our risk of breast cancer. Mammograms are useful at detecting DCIS (early breast cancer) and calcifications.
It can take 40 years for cancer to show up after exposure to radiation, so for women under 50, annual mammograms increase risk. Mammography reduces the death rate by 30 percent in women over 50 who have annual mammograms, as tumours are detected earlier; however, it increases the death rate from cancer 30-50 percent when performed annually in women under 50, as women accumulate radiation toxicity.
A mammogram is recommended if you find a lump and need an accurate diagnosis. Know that mammograms are not conclusive; if the lump is there and persists but the mammogram looks fine, it is imperative to have another test to find out what kind of mass it is. This test might be an ultrasound, fine needle aspiration, biopsy or MRI.
Limitations and Risks of Mammography:
- In the U.S., one in two women will have at least one false positive result, causing increased anxiety and worry[iv]
- Mammography is less effective for women under 50, women with dense breasts, implants, fibrocystic breasts, or on hormone replacement therapy.[v] As breast density increases, the ability of mammography to detect breast cancer decreases.[vi]
- There is a risk of rupture of encapsulation of a cancerous tumour. Twenty-two pounds of pressure is sufficient to rupture an encapsulated tumour; mammography uses 42 pounds of pressure, potentially causing cancer cells to be released into the bloodstream or lymph[vii]
- Increased radiation exposure from mammography confers a slightly increased risk of breast cancer, particularly if begun before age 40
- Women most vulnerable to breast cancer (with the BRCA1/2 genes) are more likely to develop breast cancer earlier because of ionizing radiation from mammography causing genetic mutations. This is evident when this group of women begins mammographic screening in their 30’s[viii]
- The sensitivity of mammography declines with decreasing tumour size and increasing breast density
- Mammography is effective in detecting small non-palpable micro-calcifications.
Ultrasounds are used in conjunction with mammography and clinical breast exam to distinguish cysts from solid tumours. Breast ultrasound is useful for women who have dense breasts (for whom mammography is less effective) and to provide further information on any abnormality detected by a mammogram. Cancers and fibroadenomas are solid, while cysts are hollow and filled with fluid. If the ultrasound demonstrates that the lump is filled with fluid, a biopsy is not necessary and if it shows that the mass is solid, then a biopsy must be carried out to determine whether it is a fibroadenoma or cancer. Ultrasounds can be carried out before a mammogram when a cyst is suspected. If it is a cyst, there is no need for a mammogram, and a woman is spared radiation exposure. Ultrasound is harmless and does not expose us to radiation.
Limitations and Risks of Ultrasound:
- As ultrasound uses sound waves to detect tissue changes, it poses no risk
- Ultrasounds are not effective in detecting small, nonpalpable tumours such as microcalcifications, which are better detected by mammography.
Clinical Breast Exams and Breast Self Exams
Clinical breast exams and breast self exams are performed by clinicians and by women on themselves. When these are performed well, they can detect at least 50% of asymptomatic cancers.[ix] These exams can detect cases of breast cancer that might be missed by mammography. Women with dense breasts are twice as likely to be diagnosed with breast cancer using clinical breast exams alone.[x]
Limitations and Risks of Clinical Breast Exam:
- With a caring and skilled examiner, there is no risk from clinical breast exam
- An undiagnosed lump may create anxiety until a confirmative diagnosis has been reached
- One study showed that the sensitivity of clinical breast exam alone is only 21%, compared to the 78% sensitivity of mammography in detecting cancerous tumours. When the two are used together, sensitivity for cancer detection is 82%[xi].
An MRI or Magnetic Resonance Imaging is a noninvasive imaging technique that uses no compression, x-rays, or radiation. An MRI creates a detailed picture of the internal structure of both breasts and axilla simultaneously and produces a digital image. It is an effective tool for women with dense breasts, and is able to detect invasive breast cancer. It can scan around breast implants. It is a good technique for young women and women who are at high risk of breast cancer or who have a family history of the disease. It is a valuable diagnostic tool when other imaging techniques are inconclusive or more information is needed. MRI can diagnose small breast lesions that may be missed by mammography.
Limitations and Risks of MRI:
- The strong magnetic field of the MRI can cause implanted medical devices to malfunction
- Occasionally someone may have an allergic reaction to the contrast material injected before the MRI
- A rare complication of MRI is a kidney disease called nephrogenic systemic fibrosis, caused by the gadolinium contrast material in patients with poor kidney function. This possibility is decreased if you drink 2 liters of water immediately after the MRI
- Breastfeeding women should be cautious of nursing within 48 hours of receiving the gadolinium contrast medium
Fine Needle Aspiration
Fine needle aspiration is easy to perform, painless, and can be carried out in a doctor’s office. It involves a needle to be inserted into the tumour and some fluid is removed. If clear fluid is removed and the tumour dissolves, it was a simple cyst however, if the fluid is bloody, cancer with a cystic component may exist, and the fluid is sent for analysis. If no fluid is obtained, a biopsy must be performed. Fine needle aspiration is the least invasive, fastest and most inexpensive way to diagnose breast cancer when a physician is skilled in the technique. Ninety percent of the time a diagnosis is established with this technique. The combination of physical exam, fine needle aspiration and mammography establishes an accurate diagnosis ninety-nine percent of the time.
Limitations and Risks of Fine Needle Aspiration:
- Because it samples only a small number of cells, there is a risk that abnormal cells may be missed or undetected
- There is a small possibility of cancer cells spreading to surrounding tissue as the needle is being withdrawn[xii]
A biopsy will confirm or negate the presence of cancer if the above tests have not been definitive. A sample of tissue is taken in one of two ways and then analyzed.
The first method is called open surgical biopsy and is ideally performed as a lumpectomy, as though the diagnosis of cancer had already been made. This reduces the need for a second surgery, should the first demonstrate breast cancer, and reduces scarring. The whole mass should be removed with a margin of normal tissue so that a pathologist can be sure that all the edges of the cancer have been taken out, and nothing remains.
The second method is called a core biopsy. For a large palpable mass, 1 to 6 slender cores of tissue are taken from different sites within it. It is most accurate for lesions over 2.5 cm in diameter and is much less invasive than an open surgical biopsy.
Limitations and Risks of Open Surgical Biopsies and Core Biopsies
- Possibility of infection or hematoma (blood clot) from open surgical biopsy
- Possibility of scarring or keloid formation
- Presence of bruising, swelling and soreness for a few days
- Risk associated with anaesthetic
- Possibility of excessive bleeding, although rareWith a core biopsy, there is a small possibility of cancer cells spreading to surrounding tissue as the needle is being withdrawn[xiii]
To learn more about real breast cancer prevention, join Sat Dharam Kaur ND and Dr. Gabor Maté May 26-31, 2014 at the University of Toronto for a 6 day workshop in the Healthy Breast Program and Mind-Body Approaches to Cancer and Health. http://www.mammalive.net/workshops
Sat Dharam Kaur ND is a naturopathic doctor who teaches breast health at the Canadian College of Naturopathic Medicine and has a private practice in Owen Sound, ON. She is the author of The Complete Natural Medicine Guide to Breast Cancer, A Call to Women: The Healthy Breast Program and Workbook and The Complete Natural Medicine Guide to Women’s Health.
She developed the Healthy Breast Program in an effort to educate women in preventing breast cancer or its recurrence. Sat Dharam has been educating health care practitioners and women in breast cancer prevention strategies since 1989.
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