It's estimated that there are 10 million cancer survivors in the United States, a figure projected to double by 2030 as the population ages and survival rates continue to improve. 1 As a result, researchers are beginning to study the distinct medical and psychosocial issues that long-term survivors face, but studies to date have been limited by several notable weaknesses in design and methodology, making results difficult to generalize.
Specifically, most research on cancer survivors has been conducted at major cancer centers in major urban centers, leading to underrepresentation of minorities, the medically underserved, the poor, and other hard-to-reach populations. 2 Second, most previous studies of survivorship have relied on small samples sizes and focused primarily on survivors of breast cancer. 3-6 Recently, researchers have begun to study survivors of other cancers, 7-10 but more research on these illnesses is needed. Third, few studies have looked beyond five years after diagnosis, 11-13 and relatively little is known about the long-term issues that cancer survivors and their families face. Finally, although there have been a few longitudinal and follow-up studies with long-term survivors, further investigation of the adjustment of cancer survivors over time is needed. 3,6 In sum, additional research targeting geographically, demographically, and diagnostically diverse cancer survivors at various defined points after diagnosis would fill the gaps in our understanding of the factors that affect cancer survivorship.
In an attempt to overcome the limitations of previous research, the American Cancer Society (ACS) Behavioral Research Center has implemented a series of studies collectively referred to as the Studies of Cancer Survivors (SCS).
Description of and rationale for the SCS.
The first of these studies is the Study of Cancer Survivors-I (SCS-I), a national, prospective, longitudinal study that includes men and women in the United States diagnosed with one of the 10 most common cancers: prostate, female breast, lung, colorectal, bladder, uterine, kidney, ovarian, skin melanoma, or non-Hodgkinlymphoma. Over 6,000 cancer survivors were enrolled and asked to complete the baseline questionnaire at approximately one year after diagnosis. The cohort of survivors will be followed for up to 10 years, and surveys are planned for one, two, five, and 10 years after diagnosis.
The second of these studies is the Study of Cancer Survivors-II (SCS-II), a national, cross sectional study of three separate cohorts: two-year, five-year, and10-yearcancersurvivors. Survivors of prostate, female breast, colorectal, bladder, uterine, and skin melanoma cancers are included in the study. SCS-II was launched to provide data on short-, medium-, and long-term survivors without having to wait for the longitudinal cohort from SCS-I to reach specific end points. Data from the close to 10,000 participants in SCS-II will also inform the design of the two-, five-, and 10-year follow-up surveys in SCS-I.
The third and final component of this research program, the Study of Cancer Survivors-Family Caregiver (SCS-FC), will track the experiences of primary family caregivers nominated by cancer survivors participating in SCS-I. This study aims to compare quality of life and functioning of cancer survivors to that of their primary family caregivers as well as gain a better understanding of the unique issues faced by cancer caregivers.
With over 16,000 cancer survivors and care-givers enrolled, the ACS Studies of Cancer Survivors will, collectively, be the largest, most diverse investigation of long-term cancer survivors to date. Also, several study design characteristics make these studies unique. By drawing large samples from population-based statewide cancer registries, the studies aim to uncover issues that affect medically underserved groups-specifically, those who are not treated at major cancer centers, live in rural areas, and lack adequate access to care. The studies' geographic diversity allows for comparisons of survivors from different regions of the country, while stratification by race and ethnicity will uncover issues unique to minority groups. The range of cancer diagnoses sampled will allow for the comparison of survivors of various types of cancer. Finally, although the studies do not include survivors of childhood cancers, adult cancer survivors between 18 and 54 years of age have been purposely oversampled in order to allow for the study of their unique psychosocial issues.
The dissemination of study results.
Enrollment in all three studies has been completed and preliminary analyses are currently underway. Initial publications will focus on study design and methodology, while subsequent publications will document the issues, concerns, and needs of cancer survivors and their loved ones as they differ across a number of variables, including cancer diagnosis and type of treatment; time since diagnosis; geography; race and ethnicity; and other medical, demographic, and psychosocial characteristics. A comparison of data from survivors and caregivers may shed light on how diagnosis, treatment, and survival of cancer affect interpersonal relationships. In addition to publishing the results of these studies, the ACS will use the findings to develop educational and informational programs for cancer survivors, health care providers, and the general public; to help set goals for improving the quality of life of people with cancer and their loved ones; and to develop empirically based, targeted interventions for those affected by cancer. Ultimately, our hope is that the ACS Studies of Cancer Survivors will help to identify the physical, emotional, and social issues faced by long-term cancer survivors and their families.
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