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Health news:

 
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

II - Mammography

10. X-ray mammography inaccuracy risks

2 good choices to prevent breast cancer

I - BREAST CANCER
 RISK FACTORS
  

II - SCREENING X-RAY MAMMOGRAPHY

III - 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

As anyone who saw them knows, mammographic images of breast tissue are all but clear. Layers of overlapping tissue structures are projected onto a 2-D film (or digital) detector and, sometimes, small abnormal tissue structures do not show, or are inconspicuous enough to remain undetected. In such case, test result is called false negative, i.e. does not detect an existing, objectively detectable malignant tissue growth.

Obviously, the consequence is that the missed breast cancer (BC) gets detected at a latter time, and at a more advanced stage.

On the other hand, often times what does appear to be a suspicious spot on the mammogram turns out to be a false alarm. Such test result is called false positive. The consequences are stress and additional test, or tests required.

However, not all false positive test results are corrected at the additional testing. It's been found that breast cancer incidence rates are consistently higher in screened populations than in those not screened, that are comparable with respect to the risk of developing breast cancer. The only explanation for this data is that a portion of the confirmed positive test results by screening mammography are so called pseudo disease, or quasi breast cancer: it appears to be abnormal, malignant growth, but would not have become symptomatic during woman's lifetime.

There are two consequences of this inaccuracy:

(1) an excess of diagnosed cancers that are actually pseudo disease, usually referred to as overdiagnosis, and

(2) correspondingly higher rate of unnecessary treatment, which is a part of mammography-related overtreatment.

Overdiagnosis is only in part caused by the inaccuracy of mammography. The test cannot differentiate between the actually malignant disease, and the one that is not. But sometimes it is also the limitation of the accessory tests used to confirm mammography result.

 By itself, overdiagnosis is undesirable for the same reason false positives are, and that is causing unnecessary stress to women labeled with breast cancer. But its consequences are much more serious, since such a woman never learns that what test detected as a malignant growth is, in effect, a benign one, which wouldn't have affected her in any way.

Inevitably, such woman takes on the entire burden of one that actually does have breast cancer, and that includes full-blown breast cancer treatment. This is not only unpleasant experience as any invasive treatment can be, it also can result in lasting damage to her health and wellbeing, such as disfigurement, or increased risk of heart-related death due to the negative effect of radiation therapy on cardiovascular system.

Following pages address in more detail the consequences of testing inaccuracy of the screening mammography - false negatives, false positive, overdiagnosis and overtreatment

 

IN THE NUTSHELL: X-RAY MAMMOGRAPHY INACCURACY RISKS

False negative risk (or rate):
FALSE NEGATIVES vs. ALL ACTUAL BC, 20-25%

False positive risk (or rate):
FALSE POSITIVES vs. TRUE NEGATIVES, 5-15%

Overdiagnosis risk (or rate):
ALL DIAGNOSED BC vs. ALL ACTUAL BC, 125%-150%
 

Related to the first two indicators of test accuracy are:

Sensitivity (odds of having existing BC test-detected):
TRUE POSITIVES VS. ALL ACTUAL BC, 30-90%

Specificity (odds of having true BC-free status test-confirmed):
TRUE NEGATIVES VS. ALL BC-FREE WOMEN, 85-95%
 

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