The evidence linking cigarette smoking and colorectal cancer risk has been inconsistent.

Electra Paskett, Ph.D., of Ohio State University in Columbus and colleagues investigated the association between smoking history and colorectal cancer among nearly 147,000 participants in the Women's Health Initiative.

After an average follow-up of about 8 years, 1,242 women were diagnosed with colorectal cancer. Increased colorectal cancer incidence was associated with more cigarettes smoked per day, more years as a smoker, and older age when the women quit smoking.

Current smokers were at an increased risk for rectal cancer, but not colon cancer, compared with never smokers. Secondhand exposure to cigarette smoke was not associated with either cancer.
 

"Our data add to the extensive evidence indicating that preventing smoking initiation and decreasing the duration of smoking might reduce colorectal cancer risk," the authors write.

This research was published recently in the Journal of The National Cancer Institute.



Adapted from materials provided by Journal of the National Cancer Institute.