Decreasing cancer deaths? Read the small prints

hiake · Oct 22, 2007

The Asterisk on Cancer Deaths

By DENISE GRADY

There was good news about cancer last week, a report that death rates in the United States have begun falling by 2.1 percent a year, nearly twice the rate of previous declines.

But the same report, by the American Cancer Society and other groups, also said certain cancers seem to be becoming more common — not hugely so, but noticeable. Among those increasing in men and women are myeloma and cancers of the thyroid and kidney. In women, melanoma and cancers of the bladder have increased; in men so have cancers of the liver and esophagus.

Why? Experts point to a mixed bag of facts, theories and educated guesses. One overarching culprit may be America’s level of obesity, which has been linked to increased risk of several types of cancer, including tumors of the kidney, liver and esophagus.

But there are much stronger risk factors for liver cancer. The major ones are the viruses that cause hepatitis B and C. In some people, those infections turn chronic and gradually lead to tumors. A vaccine that can prevent hepatitis B is used routinely in the United States. But not every country uses it, and liver cancer here may be rising in part because of cases among immigrants.

Hepatitis C is more of a homegrown problem. There is no vaccine, and infections surged in the 1960s and 1970s among drug users who shared needles. The virus then spread into the blood supply and may have infected tens of thousands of transfusion recipients before a test was developed to screen donated blood. Liver cancer is still turning up in people infected decades ago.

When it comes to thyroid cancer, researchers do not know whether the incidence of the disease is actually increasing, or simply being diagnosed more often because of improved tests. But it is a cause for concern. Increases in kidney cancer can probably be traced mostly to increased detection. As for melanoma, the increases probably come from both better detection and a real rise in cases due to sun exposure, researchers said.

Smoking raises the risk of bladder cancer. Rates in women may be rising because they started smoking, and quitting, later than men did, said Elizabeth Ward, director of cancer surveillance for the American Cancer Society.

There has been a similar trend with lung cancer. But over all, men have much higher rates of bladder cancer, possibly due to higher smoking rates and chemical exposures on the job.

Trends in myeloma, a bone marrow cancer, have researchers puzzled.

“It could be improvements in diagnosis,” Dr. Ward said. “It bears looking into, though, because it is more common in blacks than whites, and I don’t think we have a huge amount of knowledge about risk factors.”

Source: http://www.nytimes.com/2007/10/21/weekinreview/21basicB.html
Click to expand...

While some forms of cancer are reducing in occurrence, other different forms of cancer are sprouting like greenery in spring due to increased (and often prolonged) exposure to chemicals whose carcinogenic ability we are uncertain about...

wind2000 · Oct 22, 2007

Dont quite think its the improvements of the diagnostics tests that show an increased rate in certain types of cancer. My guess would probably due to lifestyle and environment. -sweat

Decreasing cancer deaths? Read the small prints

hiake Vardøgr of da E.Twin

wind2000 Self Schemata