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Cancer Prevention Study-3 (CPS-3)

The Cancer Prevention Study-3 (CPS-3) is a large, geographically and racially/ethnically diverse US cohort of 300,000 participants who were cancer free when they enrolled between 2006 to 2013 and who are continuing to be studied.

CPS-3: Past, Present, and Future

In December 2013, the American Cancer Society (ACS) launched Cancer Prevention Study-3 (CPS-3) when ACS completed its initial recruitment.

Who we invited: Our Cancer Prevention and Survivorship Team invited men and women between the ages of 30 and 65 who had no personal history of cancer to participate in the study.

Who we enrolled: The goal was to enroll at least 300,000 adults, and we enrolled approximately 303,500 from various racial and ethnic backgrounds from across the United States and Puerto Rico. The average age at enrollment was 47 years.

See the CPS-3 FAQs to learn more.

map of US to show number of CPS-3 participants from each state; colors are light and dark blue, red, and gray

How we did it: The successful completion of this enrollment was possible because of the partnership of ACS staff and over 30,000 volunteers. 

We enrolled participants at:

  • Over 800 Relay For Life events
  • 100 ACS events—such as Making Strides Against Breast Cancer
  • Over 2,000 corporate, hospital, and community partner-hosted events

What it means to be a CPS-3 participant: All 300,000 participants enrolled in CPS-3 by completing a survey, and 99% of CPS-3 participants provided a blood sample at enrollment. Starting in 2015, every 3 years, we've sent out Follow-up Surveys to ask for both new and updated information, such as exposure to COVID-19 or changes in weight, diet, and physical activity. These Triennial Surveys also ask about recent cancer diagnoses and many other medical conditions and medications.

Why we collect biospecimens: Researchers use blood, urine, and stool samples to investigate genetic, epigenetic, and metabolomic markers associated with cancer or with cancer risk factors, and to better understand how those markers interact with various lifestyle and environmental exposures. Many thousands of participants have agreed to take part in various CPS-3 substudies, providing urine, stool, or additional blood samples, as well as answering more specific surveys, wearing activity monitors, and more. 

How long the study will last: The CPS-3 study will last 40 years. We mailed our first follow-up survey in 2015 and will continue to send one every 3 years until the year 2043. The next follow-up survey will be sent in Spring 2024.

How we keep improving: CPS-3 is committed to incorporating the latest technologies into every aspect of our research, including data collection and analysis, participant engagement, results delivery, and data security. 

Why Our Participants Remain Dedicated to CPS-3

There's no better way to understand the impact of CPS-3 on cancer research than to hear some participants and researchers talk about their motivation for becoming involved and why they're committed for the long haul"

Alpa V. Patel, PhD

Senior Vice President, Population Science

American Cancer Society

asian woman wearing turquoise patterned shirt

The CPS-3 Participant Portal: We're relaunching the Participant Portal with a whole new design and platform. See the FAQs to learn all about it.

Substudies—Smaller Cohorts for More Targeted Research

In addition to the triennial follow-up surveys we send, we also invite CPS-3 participants to volunteer for substudies, which allow us to collect more detailed information about specific risk factors for cancer, such as physical activity. 

Examples of some recent substudies: 

CPS-3 News

Red and blue survey icon

2024 Triennial Survey Has Launched
Online survey ready for you to answer.

CPS-3 Substudies

red drop of blood

Repeat Blood Substudy

Collecting a second blood sample to study biological changes over time.

close up of feet in fitness shoes walking on street

Accelerometry Substudy
Using wearables to track daily physical activity

gray outline of person with intestines in blue with an enlarged inset of colorful germs smaller inset of germs coming from mouth

Gut & Oral Microbiome Substudy
Collecting stool and saliva samples to study the microbiome in the gut and mouth

Contact Us

CPS-3 participants:
888-604-5888 Mon.-Fri. 9 AM – 5 PM EST 

See our Data Access Policies and Procedures

Other inquiries:
Contact: Alpa V. Patel, PHD, Senior Vice President, Population Science

close up of feet in fitness shoes walking on street

Accelerometry Substudy

In fall 2023, we successfully met our goal of recruiting over 20,000 CPS-3 participants to take part in the accelerometry substudy. Substudy participants wear personal activity monitors (accelerometers) around their waist for 7 days while they’re awake.

We’ll use the data from these monitors to study more detailed patterns of physical activity and sitting time than we can through surveys alone. That information will improve the understanding of how physical activity and sitting time affect overall health and the risk of cancer as well as other diseases.

To learn more, see the Accelerometry FAQs, Activity Monitor Instruction Worksheet, and Activity Monitor Instruction video.

Gut & Oral Microbiome Substudy

The gut microbiome consists of microorganisms (such as the bacteria, fungi, and viruses) that live inside our digestive tract, and the oral microbiome consists of the microorganisms that live inside our mouths. Every person’s microbiome is uniquely shaped by their diet, lifestyle, genetics, and environmental factors. 

In the fall of 2023, we successfully completed our collection of over 10,000 paired stool and saliva samples. We will use these samples, along with the 3,000 stool samples collected from 2020 through 2021, to investigate the role of the gut and oral microbiomes in overall health and the risk for developing cancer.

To learn more about this study, see the study overview sheet, or watch the overview video or instructions video.

How CPS-3 Participants Are Contributing to Cancer Research

Many studies published by American Cancer Society researchers and other researchers across the United States use data from the Cancer Prevention Studies (CPS-II and CPS-3) and substudies. 

Here are some recent articles on that describe such studies. We couldn't have made these findings without participants who took the time and made the effort to answer surveys, wear accelerometers, and supply samples of blood, urine, and saliva.

CPS-3 Participants Newsletter Archive

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