PROSTATE, LUNG, COLORECTAL & OVARIAN CANCER SCREENING TRIAL (PLCO)

About the Participants and the Screening Tests

Who is participating?

Women and men joined the PLCO Cancer Screening Trial between 1992 and 2001. The trial is now closed, but is still actively following up on participants. Participants were between the ages of 55 and 74, and were diagnosed as NOT having prostate, lung, colorectal, or ovarian cancer when they joined the trial. Those wanting to join also were not being treated for any other type of cancer.

What do the participants do in PLCO?

Upon entry, participants were divided by chance into one of two study groups. The control group receives routine health care with their primary care physician. The screened group receives a series of exams to detect prostate, lung, colorectal and ovarian cancer.

Both women and men are screened for colorectal cancer through sigmoidoscopy and lung cancer with a chest X-ray.

Women are screened for ovarian cancer with both the CA125 test and a transvaginal ultrasound (TVU).

All men receive the Prostate Serum Antigen (PSA) test and digital rectal examination (DRE) to detect the presence of prostate cancer.

Participants in the screened group undergo exams for a total of six years, and receive follow-up for another 10 years. The schedule of screening exams is below:

Test	Frequency
Prostate Serum Antigen (PSA)	Initial visit, annually for 5 years
Digital Rectal Exam (DRE)	Upon entry, annually for 3 years
Chest X-ray	Smokers Upon entry, annually for 3 years
Chest X-ray	Never Smokers Upon entry, annually for 2 years
Sigmoidoscopy	Upon entry, one after 5 years in study
Transvaginal Ultrasound (TVU)	Upon entry, annually for 3 years
CA125	Initial visit, annually for 5 years

Additionally, all participants complete a study questionnaire once a year for up to 16 years, or the duration of the study.