High weight associated with risk of colorectal tumors without microsatellite instability

Mar 06, 2010

The increased risk of colorectal cancer associated with obesity may be largely restricted to tumors that have no or low microsatellite instability (MSI), a common condition in most colorectal cancers, according to a new study published online March 8 in the Journal of the National Cancer Institute.

This study was undertaken because little is know about the associations between and adult weight gain and the risk of colorectal overall and by tumor MSI status.

Peter T. Campbell, Ph.D., of the Epidemiology Research Program at the American Cancer Society in Atlanta, and colleagues performed a case-control study of subjects with incident colorectal cancer and their unaffected sex-matched siblings to evaluate associations between being overweight or obese (defined according to body mass index) and adult weight change and colorectal cancer risk. They evaluated the associations with cancer risk, overall and by tumor MSI status, assessed at up to 10 markers for microsatellite stability. Patients that are diagnosed with tumors that are microsatellite-stable or MSI-low have lower 5-year survival rates than patients with tumors that are MSI-high.

Recent body mass index (people over 30 kg/m2 or more, the cut off for obesity) was positively associated with overall risk of colorectal cancer for men and women combined. It was also associated with risk of MS-stable and MSI-low colorectal tumors, but not with the risk of MSI-high tumors.

"Our data also suggest that the associations between [body mass index] and adult weight gain and the risk of colorectal cancer differ between MS-stable and MSI-high tumors… suggesting differing underlying etiologies for according to tumor MSI," the authors write.

In an accompanying editorial, Shuji Ogino, M.D., Ph.D, of the Department of at the Dana-Farber Cancer Institute, and Harvard Medical School in Boston, and Meir Stampfer, M.D., of the Departments of Epidemiology and Nutrition at the Harvard School of Public Health, in Boston, said that this type of approach (the convergence of traditional epidemiology and traditional pathology research) will continue to provide useful insights on carcinogenic processes, specifically our understanding of how particular exposures influence carcinogenesis.

The editorialists write: "…These molecular pathological epidemiology data imply that molecular markers (such as MSI) can be used to classify colorectal cancers into distinct subtypes, which have implications for both etiology and prevention."

Explore further: Cancer: Tumors absorb sugar for mobility

add to favorites email to friend print save as pdf

Related Stories

Strong link between obesity and colorectal cancer

Dec 14, 2007

A clear, direct link between obesity and colorectal cancer, the second most common form of cancer in Australia with more than 12,000 new cases each year, has been shown in a new analysis by The George Institute for International ...

Helicobacter pylori and EBV in gastric carcinomas

Feb 10, 2010

Mechanisms of gastric carcinogenesis are still not yet understood. Studies have linked genetic and epigenetic factors or microbiological agents to gastric cancer, but they didn't look for these events together. Dr. Ferrasi ...

Aspirin shows promise for colon cancer patients

Aug 11, 2009

Men and women who were diagnosed with colorectal cancer and began regular use of aspirin had a lower risk of overall and colorectal cancer death compared to patients not using aspirin, according to a study in the August 12 ...

Recommended for you

Cancer: Tumors absorb sugar for mobility

4 hours ago

Cancer cells are gluttons. We have long known that they monopolize large amounts of sugar. More recently, it became clear that some tumor cells are also characterized by a series of features such as mobility or unlikeliness ...

Early hormone therapy may be safe for women's hearts

13 hours ago

(HealthDay)—Healthy women at low risk of cardiovascular disease may be able to take hormone replacement therapy soon after menopause for a short time without harming their hearts, according to a new study.

Low yield for repeat colonoscopy in some patients

14 hours ago

(HealthDay)—Repeat colonoscopies within 10 years are of little benefit to patients who had no polyps found on adequate examination; however, repeat colonoscopies do benefit patients when the baseline examination was compromised, ...

Cell's recycling center implicated in division decisions

16 hours ago

Most cells do not divide unless there is enough oxygen present to support their offspring, but certain cancer cells and other cell types circumvent this rule. Researchers at The Johns Hopkins University have now identified ...

User comments : 0