Colon CarcinomaNCT01696981
Screening for Colorectal Cancer in Older Patients (PLCO Screening Trial)
A study testing Screening Questionnaire Administration and Sigmoidoscopy in people with Colon Carcinoma and Rectal Carcinoma, run by National Cancer Institute (NCI) at 1 site in United States.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 55 to 74 years
- Conditions the study is for
- Colon Carcinoma, Rectal Carcinoma
- What is being tested?
- Screening Questionnaire Administration and Sigmoidoscopy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 154,900 participants
- Where
- 1 siteUnited States
- Study dates
- 16 Nov 1993to 30 Jun 2027
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 55 to 74 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
None listed.
Who cannot join
- Men and women who at the time of randomization are less than 55 or greater than or equal to 75 years of age
- Individuals undergoing treatment for cancer at this time, excluding basal-cell and squamous-cell skin cancer
- Individuals with known prior cancer of the colon, rectum, lung, prostate
- This includes primary or metastatic PLCO cancers
- Individuals with previous surgical removal of the entire colon, one lung, or the entire prostate (men only)
- Until October 1996, women with previous surgical removal of both ovaries were excluded from the trial. In order to increase the enrollment of women into the trial, beginning in October 1996, these women were no longer excluded for this reason.
Show all 14Show fewer
- Individuals who are participating in another cancer screening or cancer primary prevention trial
- Males who have taken Proscar/Propecia/finasteride in the past 6 months
- NOTE: Individuals who are already enrolled in the trial when their physician prescribes finasteride are not prevented from taking this medication. As a result, these participants will continue to be screened and followed just as those participants who are not on finasteride.
- NOTE: Men who are taking Tamoxifen are not excluded from any part of the PLCO Screening Trial.
- Prior to April 1, 1999 women were excluded from the trial if they were currently taking or had taken Tamoxifen or Evista\Raloxifene in the past 6 months. As of April 1999 based on a decision from the PLCO Ovary Subcommittee, women who have or are currently taking Tamoxifen or Evista\Raloxifene are not excluded from participation.
- Individuals who are unwilling or unable to sign the informed consent form
- Males who have had more than one PSA blood test in the past three years
- Individuals who have had a colonoscopy, sigmoidoscopy, or barium enema in the past three years
Trial locations and contacts
1 site in 1 country.
United States1 site
National Institutes of Health Clinical Center
Bethesda, Maryland, 20892
About this study
Official title: Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer 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.
Read the detailed description
PRIMARY OBJECTIVES:
- 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.
SECONDARY OBJECTIVES:
- 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.
- Conditions
- Colon Carcinoma, Rectal Carcinoma
- Being tested
- Screening Questionnaire Administration, Sigmoidoscopy
- Medical subject headings
- Colonic Neoplasms, Rectal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Screening Questionnaire AdministrationOther
Undergo questionnaire assessments
SigmoidoscopyProcedure or surgery
Also called Proctosigmoidoscopy
Undergo a flexible sigmoidoscopy
| Study group | Role | What they receive |
|---|---|---|
| Colorectal Screening | Active comparator | 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. Receives: Other: Screening Questionnaire Administration; Procedure: Sigmoidoscopy |
| Control | No intervention | Participants receive standard medical care. Participants complete a DHQ at baseline. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Colorectal Cancer Deaths
Colorectal cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate.
Measured: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal Cancer Death Rates
Colorectal cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate. Rate is the number of deaths divided by person years of follow-up in the study.
Measured: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Secondary outcomes (7)
Deaths From All Causes
Deaths from all causes were compared between the colorectal cancer screening arm and the usual care arm.
Measured: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Death Rates From All Causes
Deaths from all causes were compared between the colorectal cancer screening arm and the usual care arm. Rate is the number of deaths divided by person years of follow-up in the study.
Measured: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal Cancer Incidence
Colorectal cancer diagnoses confirmed by medical record abstraction.
Measured: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal Cancer Incidence Rates
Colorectal cancer diagnoses confirmed by medical record abstraction. Incidence rate (cumulative) defined as colorectal cancer diagnoses divided by person years at risk for colorectal cancer.
Measured: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Complications of Diagnostic Evaluation Following a Positive Screening Test
Number of participants who experienced complications during diagnostic work-up of a positive colorectal examination.
Measured: One year from screening examination
T0 (Baseline) FSG Screening Results
Flexible sigmoidoscopy (FSG) result
Measured: T0 (at study entry)
T3/T5 FSG Screening Result
Flexible sigmoidoscopy (FSG) result
Measured: T3 (three years after entry) or T5 (five years after entry)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Oct 2012 (estimated)
- Study start16 Nov 1993
- Primary completion21 May 2012
- Study completion30 Jun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for Colon CarcinomaStudies of the same condition, open and under way.
- More trials run by National Cancer Institute (NCI)The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Screening
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Investigator
- Enrolment
- 154,900 participants (actual)
Sponsor and investigators
- Lead sponsor
- National Cancer Institute (NCI)
- Sponsor type
- US National Institutes of Health
- Responsible party
- Sponsor
- Investigators
- Christine D Berg, Principal investigator, National Cancer Institute (NCI)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01696981
- Sponsor's protocol ID
- NCI-2012-01757
- Other IDs
- NCI-2012-01757, CDR0000078532, NCI-P93-0050, PLCO-1, PLCO-Colorectal
- Status last verified
- Jul 2026
- First submitted
- 28 Sep 2012
- Last updated
- 24 Jul 2026
- Results posted
- Yes, on ClinicalTrials.gov
Publications
Malcomson FC, Shams-White MM, Reedy J, Huang WY, Moore SC, Loftfield E. Adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research Cancer Prevention Recommendations and risk of lifestyle-related cancers in the prostate, lung, colorectal, and ovarian cancer screening trial. BJC Rep. 2025 Nov 19;3(1):81. doi: 10.1038/s44276-025-00195-6.
PubMed 41261199Fan Z, Zhang Y, Yao Q, Liu X, Duan H, Liu Y, Sheng C, Lyu Z, Yang L, Song F, Huang Y, Song F. Effects of joint screening for prostate, lung, colorectal, and ovarian cancer - results from a controlled trial. Front Oncol. 2024 Apr 29;14:1322044. doi: 10.3389/fonc.2024.1322044. eCollection 2024.
PubMed 38741776Jiang Y, Xie Q, Chen R. Breast Cancer Incidence and Mortality in Relation to Hormone Replacement Therapy Use Among Postmenopausal Women: Results From a Prospective Cohort Study. Clin Breast Cancer. 2022 Feb;22(2):e206-e213. doi: 10.1016/j.clbc.2021.06.010. Epub 2021 Jun 26.
PubMed 34548240Wang K, Wu Q, Li Z, Reger MK, Xiong Y, Zhong G, Li Q, Zhang X, Li H, Foukakis T, Xiang T, Zhang J, Ren G. Vitamin K intake and breast cancer incidence and death: results from a prospective cohort study. Clin Nutr. 2021 May;40(5):3370-3378. doi: 10.1016/j.clnu.2020.11.009. Epub 2020 Nov 16.
PubMed 33277073Kunzmann AT, Coleman HG, Huang WY, Cantwell MM, Kitahara CM, Berndt SI. Fruit and vegetable intakes and risk of colorectal cancer and incident and recurrent adenomas in the PLCO cancer screening trial. Int J Cancer. 2016 Apr 15;138(8):1851-61. doi: 10.1002/ijc.29922. Epub 2015 Dec 8.
PubMed 26559156Kunzmann AT, Coleman HG, Huang WY, Kitahara CM, Cantwell MM, Berndt SI. Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Am J Clin Nutr. 2015 Oct;102(4):881-90. doi: 10.3945/ajcn.115.113282. Epub 2015 Aug 12.
PubMed 26269366
Study at a glance
From the registry record, last updated by the sponsor on 24 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial
- ClinicalTrials.gov ID
- NCT01696981
- Acronym / sponsor ID
- NCI-2012-01757
- Conditions
- Colon Carcinoma, Rectal Carcinoma
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 154,900 participants (actual)
- Lead sponsor
- National Cancer Institute (NCI)US National Institutes of Health
- Study start
- 16 Nov 1993 (actual)
- Primary completion
- 21 May 2012 (actual)
- Study completion
- 30 Jun 2027 (estimated)
- First posted
- 2 Oct 2012 (estimated)
- Results
- Posted 21 Jul 2014
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
PRIMARY OBJECTIVES:
- 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.
SECONDARY OBJECTIVES:
- 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.
Study design
- Primary purpose
- Screening
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Colorectal Screening | Active comparator | Other: Screening Questionnaire Administration, Procedure: SigmoidoscopyParticipants 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. |
| Control | No intervention | –Participants receive standard medical care. Participants complete a DHQ at baseline. |
Who may qualify
- Ages
- 55 to 74 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (0 listed)
Key exclusion criteria (14 listed)
- Men and women who at the time of randomization are less than 55 or greater than or equal to 75 years of age
- Individuals undergoing treatment for cancer at this time, excluding basal-cell and squamous-cell skin cancer
- Individuals with known prior cancer of the colon, rectum, lung, prostate
- Individuals with previous surgical removal of the entire colon, one lung, or the entire prostate (men only)
- Individuals who are participating in another cancer screening or cancer primary prevention trial
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Screening Questionnaire AdministrationUndergo questionnaire assessments | Other | Colorectal Screening |
| SigmoidoscopyAlso: ProctosigmoidoscopyUndergo a flexible sigmoidoscopy | Procedure or surgery | Colorectal Screening |
Primary outcome
Colorectal Cancer Deaths
Time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate.
Colorectal Cancer Death Rates
Time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate. Rate is the number of deaths divided by person years of follow-up in the study.
7 secondary outcomes
Deaths From All Causes
Time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Death Rates From All Causes
Time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal Cancer Incidence
Time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Colorectal Cancer Incidence Rates
Time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.
Complications of Diagnostic Evaluation Following a Positive Screening Test
Time frame: One year from screening examination
T0 (Baseline) FSG Screening Results
Time frame: T0 (at study entry)
T3/T5 FSG Screening Result
Time frame: T3 (three years after entry) or T5 (five years after entry)
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Jul 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 41261199Malcomson FC, Shams-White MM, Reedy J, Huang WY, Moore SC, Loftfield E. Adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research Cancer Prevention Recommendations and risk of lifestyle-related cancers in the prostate, lung, colorectal, and ovarian cancer screening trial. BJC Rep. 2025 Nov 19;3(1):81. doi: 10.1038/s44276-025-00195-6.
- Derived from this study: PubMed 38741776Fan Z, Zhang Y, Yao Q, Liu X, Duan H, Liu Y, Sheng C, Lyu Z, Yang L, Song F, Huang Y, Song F. Effects of joint screening for prostate, lung, colorectal, and ovarian cancer - results from a controlled trial. Front Oncol. 2024 Apr 29;14:1322044. doi: 10.3389/fonc.2024.1322044. eCollection 2024.
- Derived from this study: PubMed 34548240Jiang Y, Xie Q, Chen R. Breast Cancer Incidence and Mortality in Relation to Hormone Replacement Therapy Use Among Postmenopausal Women: Results From a Prospective Cohort Study. Clin Breast Cancer. 2022 Feb;22(2):e206-e213. doi: 10.1016/j.clbc.2021.06.010. Epub 2021 Jun 26.
- Derived from this study: PubMed 33277073Wang K, Wu Q, Li Z, Reger MK, Xiong Y, Zhong G, Li Q, Zhang X, Li H, Foukakis T, Xiang T, Zhang J, Ren G. Vitamin K intake and breast cancer incidence and death: results from a prospective cohort study. Clin Nutr. 2021 May;40(5):3370-3378. doi: 10.1016/j.clnu.2020.11.009. Epub 2020 Nov 16.
- Derived from this study: PubMed 26559156Kunzmann AT, Coleman HG, Huang WY, Cantwell MM, Kitahara CM, Berndt SI. Fruit and vegetable intakes and risk of colorectal cancer and incident and recurrent adenomas in the PLCO cancer screening trial. Int J Cancer. 2016 Apr 15;138(8):1851-61. doi: 10.1002/ijc.29922. Epub 2015 Dec 8.
- Derived from this study: PubMed 26269366Kunzmann AT, Coleman HG, Huang WY, Kitahara CM, Cantwell MM, Berndt SI. Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Am J Clin Nutr. 2015 Oct;102(4):881-90. doi: 10.3945/ajcn.115.113282. Epub 2015 Aug 12.
Related trials for Colon Carcinoma
Not yet recruitingPhase 1
Hepatic Artery Infusion of Carfilzomib in Participants With Liver Metastatic Disease Previously Treated With Hepatic Artery Infusion Pump Therapy
Colorectal Neoplasms, Neoplasms
Recruiting
The Vanguard Study: Testing a New Way to Screen for Cancer
Bladder Carcinoma, Breast Carcinoma
Not yet recruitingPhase 2
SAMe in Prevention of Oxaliplatin-associated Liver Injury
Colorectal Cancer, Liver Metastases
RecruitingPhase 1
A Study of ERAS-0015 in Patients With Advanced or Metastatic Solid Tumors
Metastatic Solid Tumors
RecruitingPhase 1
Anti-Mesothelin TNaive/SCM hYP218 (TNhYP218) CAR T Cells in Participants With Mesothelin-Expressing Solid Tumors Including Mesothelioma
Mesothelioma, Neoplasms
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Christine D Berg principal investigator
National Cancer Institute (NCI)
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Screening Questionnaire Administration and Sigmoidoscopy in people with Colon Carcinoma and Rectal Carcinoma, run by National Cancer Institute (NCI) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 0 inclusion and 14 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 24 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 21 Jul 2014). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Colorectal Cancer Deaths (time frame: Events through 13 years of follow-up or through December 31, 2009; median follow-up 12.1 years.). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01696981, which also lists 6 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Jul 2026.