Posts Tagged ‘colon cancer’

Colon Cancer Deaths Drop As Tests Increase

Wednesday, April 7th, 2010

According to medical researchers concluding the largest study of the procedure so far this is good news for Americans.

The colonoscopy is considered the gold standard for colon cancer screening and is used in millions of people every year.  Until now, it has not been clear how its widespread use impacts the disease’s overall death toll.

The new report, based on close to 2.5 million Canadians, shows that for every one-percent increase in colonoscopy use, the risk of death from colon cancer dropped three percent.  According to the American Association for Critical Illness Insurance there were 1.4 million new cancer cases in the United States.  Approximately 10 percent were colon cancer cases.

During a colonoscopy exam, the doctor inserts a slim, flexible tube into the rectum. A camera at the tip of the tube shows the inside of the colon and allows the doctor to identify small cell clumps that might one day turn into a cancer tumor. The tube, or scope, can also be used to biopsy or remove the abnormal cells.

For their study, researchers used healthcare databases from Ontario, Canada, to link colonoscopy rates and colon cancer deaths in the province over 14 years. 

They followed more than 2.4 million people, who were between 50 and 90 years old at the outset of the study and did not have colon cancer. By 2006, about 1 in 100 had died from the disease, which mostly attacks older people.

Over the same period, as colonoscopy rates nearly quadrupled, the risk of dying from colon cancer tapered steadily, even after accounting for factors such as income and age.

Hormone Replacement May Lower Cancer Risk

Saturday, February 6th, 2010

Researchers followed nearly 57,000 California teachers to examine hormone replacement therapy (HRT) impact.  They found that women who were using HRT at the outset were 36 percent less likely to develop colon cancer over the next decade than those who had never used HRT. 

Of the 34,433 HRT users, 193 were diagnosed with colon cancer during the study period; that compared with 151 cases among the 13,778 women who had never used hormone replacement. 

HRT — with either estrogen alone or a combination of estrogen and progestin — was linked to a lower colon cancer risk even when the researchers accounted for the women’s age, weight, exercise levels and race.  According to the American Association for Critical Illness Insurance, a non-profit educational organization that tracks data related to cancer and heart diseases, older age and African-American race are risk factors for colon cancer.  There is evidence linking obesity and a sedentary lifestyle to the disease as well. 

The findings, reported in the American Journal of Epidemiology, support the theory that estrogen offers some protection against colon cancer.  Some past studies have linked not only HRT, but also use of birth control pills, to a lower colon cancer risk. And lab experiments have shown that estrogen may inhibit tumor development in the colon by affecting cell growth, or by lowering levels of a cancer-linked hormone called IGF-1. 

However, no one is recommending that women take HRT to ward off colon cancer. Millions of women stopped using the hormones after a large U.S. government study in 2002 found that postmenopausal women given HRT had higher risks of heart attack, stroke, breast cancer and blood clots than women given an inactive placebo. 

As a result, medical experts now advise that while HRT is effective at relieving menopausal symptoms — like hot flashes and vaginal dryness — women should take it at the lowest dose and for the shortest time possible. 

The findings are based on 56,864 menopausal women who took part in the California Teachers Study, a health study begun in 1995. Most of the women were past menopause at the outset, and 61 percent were currently using HRT.  Over the next decade, 442 women were diagnosed with colon cancer. 

While women who were current HRT users at the start of the study showed a lower risk of the disease, the same was not true of those who were former users.  The researchers note that the implications of that finding, if any, are not yet clear. 

Family history of colon cancer is an established risk factor for the disease, but only one study, according to Henderson’s team, has looked at whether family history affects the link between HRT and colon cancer risk — and it found no evidence that it did.

Smoking Exposure Now Linked to Colon And Breast Cancers

Saturday, December 5th, 2009

Two studies strengthen the case for the dangers of secondhand smoke for people exposed to fumes as children and as adults.  According to the American Association for Critical Illness Insurance, some  17 cancers are now attributed to smoking.  Cancer and heart disease are the major critical illnesses impacting millions of Americans yearly.

Inhaling secondhand fumes may raise a woman’s odds for breast cancer or a child’s lifetime risk for lung malignancies according to the studies.  Another study found that long-term smokers have a higher risk of developing colorectal cancer, a finding that factored into the recent decision by the International Agency for Research on Cancer (IARC) to assert that there is “sufficient” evidence to link the two, up from its previous “limited” evidence. 

In preparing their reports, the researchers adjusted for other colorectal cancer risk factors, such as not getting screened, obesity, physical activity and eating a lot of red or processed meats.   They noted that people who smoke are already more likely to engage in these types of behaviors. 

This study followed almost 200,000 people over 13 years.  According to the medical researchers, current smokers had a 27 percent increased risk of colorectal cancer and former smokers a 23 percent increased risk compared with people who had never smoked. 

People who had smoked for at least half a century had the highest risk — 38 percent higher than never smokers — of developing colorectal cancer.  People who ceased smoking before the age of 40 or who had not smoked for 31 or more years had no increased risk. 

Other studies focused on the risk of secondhand smoke, or passive smoking. In one, children exposed to secondhand smoke had a higher risk of developing lung cancer as adults, researchers from institutions including the U.S. National Cancer Institute found. In another, California researchers found that adult non-smoking women who had spent long periods of time in smoking environments upped their odds of developing postmenopausal breast cancer. 

The breast cancer findings were seen mostly in postmenopausal women, with a 17 percent higher risk for those who had had low exposure, a 19 percent increased risk for those with medium exposure and a 26 percent increased risk for those who had high long-term exposure over their lifetime. 

The studies were published in the December issue of Epidemiology, Biomarkers & Prevention,

High-Definition Colonoscopy Detects More Polyps

Saturday, October 31st, 2009

According to researchers from the Mayo Clinic it appears that high-definition colonoscopy detects more precancerous polyps.  The difference could be as much as 20 percent.

 Approximately 14 million colonoscopies are performed each year according to the American Association for Critical Illness Insurance, the industry organization that tracks and reports data related to critical illnesses.  Some 745,000 men were diagnosed with cancer each year, roughly 10 percent with colon cancer. 

The findings, presented at the annual meeting of the American College of Gastroenterology in San Diego, Calif., are not only important because a large group (2,430) of patients participated, but they resulted from the only study to date that has compared these two methods in a general clinical practice setting, among all the patients who needed a colonoscopy and with all the physicians who performed it. 

An endoscope is the lighted tube inserted into the colon and rectum to look for, and remove, polyps. A high-definition endoscope uses both a high-definition video chip and HD monitors (like HD television) that increase the resolution of the image. 

Researchers found that the rate of detection of adenomas — polyps that are likely to become cancerous — was 29 percent among patients who were scanned with high-definition endoscopes, versus 24 percent for those in which standard endoscopes were used.

Stem Cell Research Offers Colon Cancer Vaccine Hope

Friday, October 9th, 2009

October 10, 2009.  Human stem cells may provide a means of creating a vaccine against colon cancer and other types of cancers.

Some 1.4 million Americans are diagnosed with cancer annually according to the American Association for Critical Illness Insurance, the national trade orgganization.  “Some 10 percent of cases in both men and women are colon cancer,” notes Jesse Slome, executive director.

American and Chinese scientists reporting noted that cancer and stem cells share many molecular and biological features.   Dr. Zihai Li, of the University of Connecticut Stem Cell Institute, said in a news release that by immunizing the host with stem cells, the researchers were are able to ‘fool’ the immune system to believe that cancer cells are present and thus to initiate a tumor-combating immune program.  The research by Li and colleagues is the first to make the connection between human stem cells and colon cancer vaccination.

 

The study authors noted that, it has long been believed that immunizing people with embryonic materials may trigger an anti-tumor response by the immune system, but this theory has never advanced beyond animal research. The finding that human stem cells may help immunize against colon cancer is new and unexpected they added.  The study was published online Oct. 7 in the journal Stem Cells.

 

The researchers vaccinated mice with human embryonic stem cells and found that the mice developed a consistent immune response against colon cancer cells. The vaccinated mice showed a dramatic decline in tumor growth, compared with non-vaccinated mice.