Aspirin, already shown to protect against heart disease and stroke, may also protect against colon cancer.
Patients who took aspirin at least four times a week for at least three months were half as likely to develop colon cancer as were patients who did not take aspirin, according to Dr. Lynn Rosenberg of the School of Public Health at the Boston University School of Medicine.
The exact amount of aspirin taken was not known, Dr. Rosenberg said.
The 11-year study compared 1,326 colon cancer patients with 4,891 patients who had other types of cancer or no cancer at all.
The study was reported in the March 6 issue of the Journal of the National Cancer Institute.
About 112,000 cases of colon cancer will be diagnosed in 1991, according to the American Cancer Society. About 53,000 people will die
from the disease during the year.
It is the third-leading cause of cancer death in Americans behind lung cancer; breast cancer for women; and prostate cancer for men.
Patients who took aspirin regularly for years but who stopped taking it at least one year prior to the study had no decreased risk of the cancer.
Dr. Rosenberg cautioned that while the results of her study were encouraging, that they were preliminary and did not prove that aspirin would protect against colon cancer.