CT Scans make increase cancer risk

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A recent study confirmed what was suspected - that some tests may actually increase the risk of cancer. One of these tests is the CT scan. The study was conducted at the UCSF.

According to this study, a CT scan at "effective dosage" delivers the same amount of radiation as 74 mammograms (and a mammogram delivers 1000 x the radiation of a chest x-ray). The researchers estimated that 1 in 274 women gets CANCER FROM the CT scan used in an angiogram (1 in 610 men). For some reason, the risks involved with a CT brain scan are significantly less... 1 in 8100 for women and 1 in 11,000 for men. They noted that the cancer risks were twice as high for men and women in their 20's having CT scans.

The number of CT scans has risen from 3 million a year to 70 million a year, the researchers said.

The technology has improved greatly since the 1980's - for one thing the scans can be done more quickly but this, according to the researchers, has been a double edged sword because it has encouraged medical providers to order multiple scans - thus again delivering more radiation.

And this study also found that the doses of radiation vary between hospitals. They suggested some type of standardization on the amount of radiation delivered and also lowering the amount of radiation delivered.

The Mammogram is another test which is acknowledged by medical providers to increase the risk of breast cancer - it delivers 1000 times the radiation of a chest X-ray.  Recently it has come under a lot of questioning because it can deliver as high as 95 percent false positives which can lead not only to anxiety but repeated mammograms (delivering MORE radiation) and invasive procedures like biopsies.  Many medical providers have opined that since we cannot really find early breast cancer, women are better off doing the non invasive self breast exam.

A CBS news story reported on the CT scan study, 12/14/09:


Dose of Radiation Varies Greatly from One Hospital to Another; Skyrocketing Scans Could Lead to 29,000 New Cancer Cases

(CBS) There were about 70 million CT scans performed in United States in 2007 - up from just 3 million in 1980. The scans, also known as CAT scans can help doctors identify tumors and internal injuries among many other uses.

But they rely on dangerous radiation to get the job done and the harms may be greater than previously thought, reports CBS News medical correspondent Dr. Jon LaPook.

After Alabama school teacher Becky Coudert had a brain CT scan in September her hair started to fall out and, according to a lawyer, "She developed a broad band of baldness from one temple to the other, from around the back of the head."

Her lawyer says she received a higher than normal radiation dose. Two other patients have come forward with similar stories. In Los Angeles, Cedars-Sinai Medical Center is being investigated for giving excess radiation to more than 250 patients during their CT scans.