Does cancer screening save lives?

Challenge

Questions about the efficacy of screening are key to impacting cancer morbidity and mortality. The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial was designed by the National Cancer Institute in the early 1990s to address these questions for the 4 cancers that make up its name.

Solution

Westat has served as the coordinating center for PLCO Cancer Screening Trial since its inception. The trial originally recruited more than 150,000 people aged 50 to 74 at 10 clinical centers, randomized them to a screening or control arm, and continues to follow them longitudinally, collecting data on cancer incidence and mortality.

After 20 years of data collection at each clinical center, the study has moved to centralized follow-up, carried out by Westat.

Westat staff contributed to the report, which appeared in the New England Journal of Medicine, about the results of screening with flexible sigmoidoscopy for colon cancer. Screening was associated with a significant decrease in colon cancer incidence and mortality.

While Westat is no longer actively collecting data from PLCO participants, the Central Data Collection Center (CDCC) conducts passive data collection activities. These include linkages to state tumor registries, the National Death Index (NDI), and the Centers for Medicare and Medicaid Services.

Results

PLCO has already helped researchers answer important questions about the early detection value of PSA testing for prostate cancer, chest X-ray for lung cancer, flexible sigmoidoscopy for colon cancer, and CA125 and ultrasound for ovarian cancer.