Approximately 30% of participants in a randomized trial of various colorectal cancer screening strategies chose to participate in screening regardless of whether they were offered an immunochemical fecal occult blood test (FOBT), sigmoidoscopy, or a choice of the two methods, according to a new study.
It is generally accepted that colorectal cancer screening reduces the incidence of and mortality from the disease. Strategies for population-based screening programs are being evaluated in several European countries, including Italy. Comparative data about rates of detection and participation and economic costs are needed to estimate the effectiveness of the various programs.
To compare participation and detection rates achievable through different strategies for invitation to colorectal cancer screening, Nereo Segnan, M.D., of the Centro Prevenzione Oncologica Regione Piemonte and Azienda Sanitaria Ospedaliera S Giovanni Battista in Torino, Italy, and colleagues conducted a multicenter, randomized trial of Italians ages 55 to 64 who were at average risk for colorectal cancer. The subjects were randomly assigned to one of five different screening options: a biennial FOBT delivered by mail; a biennial FOBT delivered through clinical practice; a choice of FOBT or sigmoidoscopy; sigmoidoscopy; or sigmoidoscopy followed by biennial FOBT.
The participation rates were similar in all five groups; approximately 27% to 30% of people chose to be screened. However, sigmoidoscopy detected approximately three times as many advanced neoplasias as did FOBT. In addition, the participation rate in the sigmoidoscopy groups was higher in men than in women and lower among subjects ages 60 to 64 than among subjects ages 55 to 59, showing different preferences in these groups.
In an editorial, Timothy R. Church, Ph.D., of the University of Minnesota School of Public Health in Minneapolis, discusses two novel aspects of this study--comparing the offer of an explicit choice between screening tests to recommendations of a specific test and to the option of doing both tests, and comparing two methods of distributing the FOBT kits. He questions whether theoretical models of screening behavior would predict the surprising finding that subjects who were given a choice between screening methods did not have a higher screening participation rate than subjects who were not given a choice.
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Tamoxifen's Association With Endometrial Cancer Risk in Pre- and Postmenopausal Women Examined
Tamoxifen use is associated with an increased risk of endometrial cancer. A new study has found that this risk is similar in pre- and postmenopausal women, increases with duration of use, and does not diminish through 5 years of follow-up after the treatment ends.
Anthony J. Swerdlow, D.Sc., of the Institute of Cancer Research in Sutton, England, and colleagues conducted a case–control study in Britain of 813 patients who had endometrial cancer following breast cancer diagnosis and 1,067 control subjects who had breast cancer but not subsequent endometrial cancer.
Overall, tamoxifen treatment was associated with 2.4 times the risk of endometrial cancer compared with no treatment. The risk increased with the duration of treatment and did not diminish in the 5 years following the end of treatment. The risk was similar in pre- and postmenopausal women. The authors write that, until further data are available, their results "suggest that the associated risk of endometrial cancer makes treatment with tamoxifen beyond 5 years questionable."
Contact: Marie Maclean, Institute of Cancer Research, +44 207 153 5359, Marie.Maclean@icr.ac.uk
Bone Density Not Related to Breast Density or Risk of Breast Cancer, Study Finds
Bone density is not related to either mammographic breast density or a woman's risk of breast cancer, according to a new study.
Mammographic breast density is one of the strongest known risk factors for breast cancer, but it is not known why breast density should affect breast cancer risk. One theory is that breast density may reflect the cumulative effects of estrogen on breast tissue. Bone mineral density may also be a marker of lifetime exposure to estrogen, but little is known about its relationship to breast density and breast cancer risk.
To evaluate the relationship between bone density, breast density, and breast cancer risk, Karla Kerlikowske, M.D., of the University of California, San Francisco, and colleagues studied women participating in the San Francisco Mammography Registry. They found that bone density was not related to either mammographic breast density or breast cancer risk. However, breast density was a strong risk factor for breast cancer even after taking into account reproductive and hormonal risk factors. The authors conclude that a component of breast density that is independent of estrogen-mediated effects may contribute to breast cancer risk.
Contact: Eve Harris, Public Affairs, University of California, San Francisco, 415-885-7277, eharris@pubaff.ucsf.edu
Higher Blood Levels of Two Components of Vitamin E Associated With Lower Risk of Prostate Cancer
A new study has found that higher blood levels of two components of vitamin E--alpha-tocopherol and gamma-tocopherol--are associated with a lower risk of prostate cancer.
The Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study showed an association between daily alpha-tocopherol supplementation and reduced prostate cancer risk. Demetrius Albanes, M.D., of the National Cancer Institute, and colleagues conducted a case–control study of men who had participated in the ATBC Study. They found that men with the highest baseline circulating concentrations of each vitamin E fraction had a lower risk of prostate cancer than men with the lowest circulating levels.
Contact: National Cancer Institute Press Office, 301-496-6641, NCIPressOfficers@mail.nih.gov
Also in the March 2 JNCI:
Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage. Visit the Journal online at http://jncicancerspectrum.oupjournals.org/.
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JNCI Journal of the National Cancer Institute