Screening for Colorectal Cancer in Older Patients (PLCO Screening Trial)
This clinical trial studies whether screening methods used to diagnose cancer of the prostate, lung, colon, rectum, or ovaries can reduce deaths from these cancers. Screening tests may help doctors find cancer cells early and plan better treatment for colorectal cancer
Other: screening questionnaire administration
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Investigator)
Primary Purpose: Screening
|Official Title:||Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial|
- Colorectal cancer-specific mortality rate [ Time Frame: Up to 13 years ] [ Designated as safety issue: Yes ]Event rates defined as the ratio of the number of events (deaths) to the person-years at the risk for the event.
- Colorectal cancer-specific incidence rate [ Time Frame: Up to 13 years ] [ Designated as safety issue: No ]Event rates defined as the ratio of the number of events (diagnosis) to the person-years at the risk for the event.
|Study Start Date:||November 1993|
|Primary Completion Date:||May 2012 (Final data collection date for primary outcome measure)|
No Intervention: Control
Participants receive standard medical care. Participants complete a DHQ at baseline.
Active Comparator: Colorectal Screening
Participants undergo a colorectal examination with a flexible sigmoidoscope at baseline and year 5. Participants complete a DQX at baseline and DHQ at year 3. An ADU (previously referred to as the PSH questionnaire) is mailed to each participant annually for 13 years to identify all prevalent and incident colorectal cancers as all deaths that occur among both screened and control subjects during the trial.
Undergo a flexible sigmoidoscopy
Other Name: ProctosigmoidoscopyOther: screening questionnaire administration
Undergo questionnaire assessments
I. To determine whether screening with flexible sigmoidoscopy (60-cm sigmoidoscope) can reduce mortality from colorectal cancer in women and men aged 55-74 at study entry.
I. To assess screening variables, other than mortality, for each of the interventions including sensitivity, specificity, and positive predictive value.
II. To assess the incidence, stage, and survival of cancer cases. III. To investigate the mortality predictive value of biologic and/or prognostic characterizations of tumor tissue as intermediate endpoints.
IV. To conduct biomolecular and genetic research into factors associated with cancer carcinogenesis and promotion, as well as the early detection of these factors.
OUTLINE: Participants in the overall PLCO study are stratified by screening center, gender, and age (55-59 vs 60-64 vs 65-69 vs 70-74). Participants are randomized to 1 of 2 arms (control vs screening).
ARM I (Control): Participants receive standard medical care. Participants complete a Diet History Questionnaire (DHQ) at baseline.
ARM II (Colorectal Screening): Participants undergo a colorectal examination with a flexible sigmoidoscope at baseline and year 5. A scheduling and tracking procedure is implemented to ensure regular attendance at repeat screens for participants screened negative or for those who are designated suspicious or positive at screening but for whom subsequent diagnostic procedures do not reveal colorectal cancer (follow-up diagnostic procedures are through their own medical care environment). Participants diagnosed with colorectal cancer via a screening test are referred for treatment in accordance with current accepted practice for appropriate stage of disease, patient age, and medical condition; a procedure is provided for contact with qualified medical personnel to insure appropriate therapy.
Participants complete a Dietary Questionnaire (DQX) at baseline and DHQ at year 3. An Annual Study Update (ADU) (previously referred to as the Periodic Survey of Health [PSH] questionnaire) is mailed to each participant annually for 13 years to identify all prevalent and incident colorectal cancers as all deaths that occur among both screened and control subjects during the trial.
After completion of screening, participants are followed up for at least 13 years.
|United States, Maryland|
|Mark O Hatfield-Warren Grant Magnuson Clinical Center|
|Bethesda, Maryland, United States, 20892|
|Principal Investigator:||Christine Berg||Mark O Hatfield-Warren Grant Magnuson Clinical Center|