• The Breast Cancer Prevention Trial, the first of its kind, is designed to determine whether tamoxifen , an
  anti-estrogen drug used to treat breast cancer, will prevent cancer, heart attacks and bone fractures in
  postmenopausal women and premenopausal women at high risk for cancer. Up to 16,000 women will
  participate in this 10-year study.
• The Prostate Cancer Prevention Study will assess the value of finasteride (Proscar) for preventing prostate
  cancer. Eighteen thousand healthy men age 55 and older will be recruited into this study. 
• The Prostate, Lung, Colorectal and Ovarian Trial (PLCO) will evaluate the effectiveness of cancer-screening
  techniques. The study will randomly divide 74,000 men and 74,000 women into either intervention (screening)
  or control (no screening) groups for four years of screening and ten years of monitoring. Screening procedures
  to be tested include the digital rectal examination, prostate specific antigen test (PSA), chest x-ray, flexible
  sigmoidoscopy , pelvic examination, serum CA-125 blood test and vaginal ultrasound . 
• The American Stop Smoking Intervention Study (ASSIST) is designed to reduce the prevalence of smoking in
  17 states to less than 15 percent of adults by the year 2000. The study is expected to reach 18 million
  smokers.
• The National Cancer Institute has joined forces with the produce and food retail industries to launch a diet and
  cancer prevention program called "5 A Day For Better Health." This program will combine supermarket
  promotions, media messages and programs in the workplace, school and community to motivate individuals to
  eat five or more servings of fruits and vegetables every day.