Tuesday, June 29, 2010

Collateral Damage In The War On Cancer

Since the war on cancer was declared by then president Nixon in 1971 much effort has been devoted to the war. So how are we doing? In 2007 there were 12 million new cases of cancer reported world wide and 7.5 million deaths.These numbers are projected to rise to 27 million new cases and 17.5 million deaths by 2050.

These figures do not suggest that what we are doing is working a s well as it might be. The other figure which, does not get quoted much is the collateral damage which is done in the war. Hang on a minute, what is collateral damage? Surely screening for and treating cancer is all good even if it doe not always work.

There is a view which is promoted in the media and by doctors(particularly those involved in cancer screening) that screening is all good and that early detection is important. There is no argument that early detection is better than late detection. There is also no doubt that some people have had their lives “saved” by early detection.

Do we know how many people are in this particular boat? Do we know how many people had unnecessary procedures including biopsies and surgery not to mention needless stress because screening tests picked up cancers that were not actually there? Do we know how many people have early cancers which f not found would not actually develop and lead to a reduction in life expectancy?

Figures are starting to emerge. The British Medical Journal published figures on mammography. The difference in deaths in women aged 40 to 55 that can be attributable to mammography screening is 0.06%. Looked at another way for every woman who would otherwise not have found the cancer and died, 1610 women need to have tests. In addition to this ten women will undergo surgery, which will provide no benefit to them, only potential complications.

With prostate screening the situation is even worse. For every cancer successfully detected and treated early, 48 men will have unnecessary surgery, which can lead to urinary incontinence and impotence in one third of cases. Another review suggested that screening led to no decrease in death rates. The inventor of the PSA test, which is used for screening(but was not developed for that use) described prostate testing as like flipping a coin.

The positioning of cancer screening as saintly leads to criticism of anyone who questions the current orthodoxy. Keep in mind that there are considerable vested interests invested in screening programs and those advocating screening may have a conflict of interest, which would not be acceptable in any other field.

Every person who has surgery or other unnecessary procedures is collateral damage in the war on cancer. Some will say this is a reasonable price to pay. Others may not see it this way. The key point is that you can only make a decision on how you want to proceed if you know all the facts.

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