Cancer Prevention Study Overviews
Cancer Prevention Study I
The Cancer Prevention Study I (CPS-I) is a prospective mortality study of approximately 1 million adult men and women enrolled between October 1, 1959 and February 15, 1960, and followed up through September 1972. Participants were recruited into the study in 25 states by approximately 68,000 volunteers for the American Cancer Society. Enrollment was by families (households). All family members age 30 years and over were recruited if at least one participating household member was 45 years or older.
At the time of enrollment, each participant completed a four-page baseline questionnaire providing information on height, weight, demographic characteristics, personal and family history of cancer and other diseases, menstrual and reproductive history (women), occupation, diet, alcohol and tobacco use, and physical activity. Supplemental questionnaires were mailed to participants in 1961, 1963, 1965, and 1972, inquiring about cancer and changes in smoking habits. These additional questionnaires were used only to confirm vital status.
The participants' vital status was determined annually (in October) from 1960 through 1965, and again in 1971 and 1972, through personal inquiries by the volunteers. At each of these 8 follow-ups, the volunteers were asked whether their enrollees were alive or dead and the date and place of all deaths. Death certificates were obtained from State Health departments.
Cancer Prevention Study II
CPS II Baseline Cohort
The Cancer Prevention Study II (CPS-II) is a prospective cohort study funded and conducted by the American Cancer Society (ACS). The goal of the study is to examine the impact of environmental and lifestyle factors on cancer etiology in a large group of American men and women. To achieve this goal, approximately 1.2 million men and women were enrolled in 1982 with the help of 77,000 American Cancer Society volunteers in 50 states, the District of Columbia, and Puerto Rico. Many of the participants were friends, neighbors, family members, or acquaintances of the volunteers.
Study participants (known as the CPS-II Baseline Cohort) completed an initial study questionnaire in 1982 that obtained information on a range of lifestyle factors such as diet, use of alcohol and tobacco, occupation, medical history, and family cancer history. These data have been examined extensively in relation to cancer mortality. Vital status of study participants is updated biennially through computerized linkage with the National Death Index. Cause of death has been documented for 99% of all deaths that have occurred. Mortality follow-up of the CPS-II Baseline Cohort is complete through 2006 and is expected to continue for many years. Over 488,000 deaths have occurred in this cohort from 1982 to 2006.
CPS II Nutrition Cohort
In 1992, a new questionnaire was mailed to a subgroup of the CPS-II Baseline Cohort to obtain detailed information on diet, to update other lifestyle factors, and to conduct prospective cancer incidence follow-up in addition to mortality follow-up. This subgroup was chosen among baseline cohort members, aged 50-74, who resided in 21 states with population-based state cancer registries (California, Connecticut, Florida, Georgia, Illinois, Iowa, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Missouri, New Mexico, New Jersey, New York, North Carolina, Pennsylvania, Utah, Virginia, Washington, and Wisconsin).
Known as the CPS-II Nutrition Cohort, this subgroup of 184,194 men and women received additional mailed questionnaires in 1997, 1999, 2001, 2003, 2005, and 2007, to update exposure information and to obtain self-reported cancer diagnoses. With permission from study participants, self-reported cancer diagnoses are verified by medical record review. Computerized linkage with state cancer registries is used to supplement self-reported information on cancer incidence. Future questionnaires are planned on a biennial basis.
CPS II Biospecimen Repository
In 1998, the CPS-II Lifelink Cohort was initiated to obtain blood samples from 40,000 surviving members of the CPS-II Nutrition Cohort that resided in urban and suburban areas. Blood collection was coordinated by American Cancer Society staff and volunteers and performed by hospital staff at community hospitals (approximately 312 hospitals in 20 states, recruited mainly from American College of Surgeons [ACOS] Commission on Cancer approved programs). Collection of blood samples for LifeLink was completed in June, 2001.
A total of 39,380 Nutrition Cohort members gave a single blood sample. The biospecimen repository was expanded to obtain buccal cell samples by mail from those participants who were unable or unwilling to give a blood sample. Collection began in January 2001, and was completed in May 2002. Buccal cell samples were received from approximately 67,000 cohort members. These blood and buccal cell samples are being stored in liquid nitrogen for epidemiologic investigations, including the role of nutritional, hormonal, and genetic factors in the development of cancer and other diseases.
Cancer Prevention Study 3
Cancer Preventions Study - 3 (CPS-3) is currently being established to replace the older cohort of CPS-II because of changes over time in the causes of cancer within populations and in our understanding of cancer etiology. Like CPS-II, the CPS-3 cohort is designed to be a long-term resource to examine the relationship between cancer incidence and mortality, and a wide range of exposures. Unlike CPS-II, CPS-3 will recruit younger and middle-aged adults (ages 30-65), and will include large numbers of nonwhite and Hispanic participants. We expect CPS-3 will become an extraordinarily valuable resource, because of its size (500,000), its diversity with respect to age, ethnicity, and geography, and the availability of blood samples and detailed questionnaire information collected over time.