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Health news:
 
June 2010 - Dec 2013

Minimizing breast cancer risk

June 2010 - Dec 2013

Minimizing breast cancer risk

May 2010

Time to move beyond salt ?

Salt hypothesis vs. reality

Is sodium bad?

April 2010

Salt studies: the latest score

From Dahl to INTERSALT

Salt hypothesis' story

March 2010

Salt war

Do bone drugs work?

Diabetes vs. drugs, 3:0

February 2010

The MMR vaccine war: Wakefield vs. ?

Wakefield proceedings: an exception?

Who's afraid of a littl' 1998 study?
 

January 2010

Antibiotic children

Physical activity benefits late-life health

Healthier life for New Year's resolution

 

December 2009

Autism epidemic worsening: CDC report

Rosuvastatin indication broadened

High-protein diet effects

 

November 2009

Folic acid cancer risk

Folic acid studies: message in a bottle?

Sweet, short life on a sugary diet

 

October 2009

Smoking health hazards: no dose-response

C. difficile warning

Asthma risk and waist size in women

 

September 2009

Antioxidants' melanoma risk: 4-fold or none?

Murky waters of vitamin D status

Is vitamin D deficiency hurting you?

 

August 2009

Pill-crushing children

New gut test for children and adults

Unhealthy habits - whistling past the graveyard?

 

July 2009

Asthma solution - between two opposites that don't attract

Light wave therapy - how does it actually work?

Hodgkin's lymphoma in children: better alternatives

 

June 2009

Hodgkin's, kids, and the abuse of power

Efficacy and safety of the conventional treatment for Hodgkin's:
behind the hype

Long-term mortality and morbidity after conventional treatments for pediatric Hodgkin's

 

May 2009

Late health effects of the toxicity of the conventional treatment for Hodgkin's

Daniel's true 5-year chances with the conventional treatment for Hodgkin's

Daniel Hauser Hodgkin's case: child protection or medical oppression?

April 2009

Protection from EMF: you're on your own

EMF pollution battle: same old...

EMF health threat and the politics of status quo
 

March 2009

Electromagnetic danger? No such thing, in our view...

EMF safety standards: are they safe?

Power-frequency field exposure
 

February 2009

Electricity and health

Electromagnetic spectrum: health connection

Is power pollution making you sick?

January 2009

Pneumococcal vaccine for adults useless?

DHA in brain development study - why not boys?

HRT shrinks brains

NEWS ARCHIVE
2009
2008
2007

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June 2010 - December 2013

III - ALTERNATIVE BREAST CANCER SCREENING TESTS

1. Alternative tests for breast cancer screening

2 good choices to prevent breast cancer

I - BREAST CANCER
 RISK FACTORS
  

II - SCREENING X-RAY MAMMOGRAPHY

3 - ALTERNATIVE TESTS

The biggest risk factor
Risk factors overview
Times change

END OF A MYTH
The whistle
Contra-argument
Last decade
Current picture

 OTHER  X-RAY TESTS
Digital standard
Tomosynthesis
Breast CT

Predisposing factors
Diet       Other

BENEFIT
Earlier diagnosis
Fewer breast cancer deaths

Gamma-ray tests
BSGI/MBI 
PEM

INITIATING  FACTORS
Radiation
Chemicals
Viruses

RISK  &  HARM

OTHER  TESTS
Breast MRI
Ultrasound
Thermography
AMAS test

INACCURACY RISKS False negative
False positive

Overdiagnosis
PROMOTING  FACTORS
Hormonal

Non-hormonal

RADIATION

Radiation primer
Screen exposure
Radiation risk
PHYSICAL EXAM
Clinical
Self-exam

Higher all-cause mortality?

• Minimizing breast cancer risk

After looking at all available evidence, we came up with somewhat vague conclusion: if there is any benefit from mammographic screening, it is marginal at best. On the other hand, the risks and negatives are certain. If so, what Gøtzsche and Olsen said more than a decade ago did withstand the test of time: screening with X-ray mammography is not justified.

The question is: is there an alternative screening test that could help diagnose breast cancer early, with a better positives-to-negatives ratio?

Alternative tests to X-ray mammography for breast cancer screening come in two main flavors: those that use ionizing radiation, and those that don't. Obviously, these latter have the advantage of not exposing breast tissue to ionizing radiation, for which we have good reasons to believe it is potentially damaging even at the relatively low doses used for screening.

However, tests that don't use ionizing radiation are not necessarily entirely safe; and some are safer than the others.

Alternative tests using ionizing radiation

Not surprisingly, officially the most serious contenders for the alternative breast cancer screening test that use ionizing radiation, also use X-rays. But an entirely different technology, using gamma rays, has been recently developed into specialized breast cancer test. It is a possible accessory screening test, and some of its promoters argue it could be more than that.

The main - and quite general - objection to the standard X-ray mammography test (either film or digital) at this point is its questionable risks-to-benefits ratio. Data strongly suggests that the benefit of screening using this test limits to a small reduction in breast cancer mortality rate, bordering with statistically insignificant.

On the other hand, its negatives - mainly resulting from its insufficient accuracy (false positives, false negatives, overdiagnosis and overtreatment) - are undoubtedly significant and, by any realistic measure, larger than the positives.

In addition, it is unclear whether screening reduces or increases total mortality rate.

The radiation dose delivered by it is generally considered sufficiently low to be acceptable. This may be so at the level of average sensitivity to radiation, but not necessarily so for individual woman, whose radiation vulnerability may be much above the average. In any instance, a test that uses ionizing radiation could be considered viable alternative to the standard X-ray test only if it

does not deliver significantly higher dose of radiation and, at the same time, significantly reduces some of all of its negatives.

For a while, as the standard mammographic test was in its full swing as the one and only screening choice, there was little effort directed toward development of a possible alternative. However, as the questions about its actual risks and benefits started surfacing and taking hold, more and more attention was turned toward such alternatives.

The simplest one was already ongoing: digitalizing the standard test, by replacing film by a digital detector - digital mammography. This allowed for more efficient, computerized image processing, although no major improvements in screening efficiency were achieved. Digital conventional mammography probably somewhat reduces the average radiation exposure, but it comes at a price of much higher cost.

More complex X-ray alternatives, like tomosynthesis and breast CT (computed tomography), were also brought to the table. Both are based on the technology of constructing 3-D image from multiple 2-D images of the breast taken from different angles. The main difference in this respect is that the former takes 2-D images from directions that cover only a small fraction of a full circle around the breast, while with the latter 2-D images are taken from all directions, covering a full circle around breast.

Either produces generally higher quality image of breast tissue than the standard mammography (either film or digital). In addition, after the 3-D image is constructed, it can be computer-examined through tiny cross-sectional slices. It is hard to say, though, whether or how much it might improve screening efficiency. The drawback is that it would significantly prolong evaluation time vs. standard mammography.

Breast tomosynthesis requires mechanical apparatus similar to that of digital mammography, so the existing units can be modified for this new test type. That is an advantage relative to breast CT, which requires completely new machine, thus its introductory cost is higher. However, the absence of breast compression with it is definitely a plus.

Another type of detection test using ionizing radiation comes from nuclear medicine, and uses gamma radiation. It works by injecting radioactive isotope (tracer) into the bloodstream, which cancer cells tend to absorb at a significantly higher rate than normal cells. As a result, cancer cells emit higher level of radiation, which make them detectable on the images made with a special camera.

In general, these tests expose patients to much higher radiation dose than X-ray mammography.

Recent modification made to the standard technology is a breast-specialized test of this type - BSGI, BMI and PEM - which succeeded in significantly reducing radiation exposure, although it is still significantly higher than with X-ray mammography. Also, the procedure is more complex, more time consuming and more costly.

Alternative tests not using ionizing radiation

The first alternative test to X-ray mammography that does not use ionizing radiation is one that you most likely heard of as being not an alternative, but the most reliable evidence that we have strongly suggests the opposite. It is, of course, physical breast exam, which can be done either by a trained medical technician (clinical breast exam, CBE), or by a woman herself (breast self-exam, BSE).

There is no good reason not to combine the two.

It is obvious why these two tests were officially sidelined in the era of X-ray mammography domination. However, in probably the most meticulous, highest quality breast cancer random controlled trial - Canada 1/2 - there was practically no difference in breast cancer mortality between the population screened with X-rays, and population that used physical breast exam.

It is hard to believe that all the mambo-jumbo with X-ray mammography was actually unnecessary; worse yet, that it may have done more harm than good. But it as well may turn out to be so.

In addition to the physical exam, there are other alternative test that do not require exposure to ionizing radiation. Two breast cancer imaging tests commonly used to confirm or clarify mammography findings without additional exposure to ionizing radiation are breast ultrasound (also called sonography) and magnetic resonance imaging (MRI). Ultrasound is quickly developing technologically, and is very promising. The MRI is not likely to become a viable option any time soon, due to its high cost and uncertainties about the effect on health of the extremely strong magnetic fields it uses.

The third technique, somewhat obscured and different with respect to the type of information it provides, is breast thermography. At present, it seems that the special role of thermography in the screening process could be to indicate, based on the breast's blood vessel pattern, the level of risk of developing breast cancer within several years.

Finally, there is a unique blood test for cancer, which is not cancer-specific, but is highly accurate in detecting the presence of malignant growth somewhere in the body. It is the anti-malignin antibody screen (AMAS). Its usefulness is limited by it being non-specific, but the AMAS test certainly should be included in the set of accessory tests that can be used when appropriate.

Following pages give more details about these alternative tests to the standard X-ray mammography, beginning with the alternative tests using ionizing radiation.

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