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Guideline American society of clinical oncology clinical practice guideline update on the use of pharmacologic interventions including tamoxifen, raloxifene, and aromatase inhibition for breast cancer risk reduction. 2009
Visvanathan K, Chlebowski RT, Hurley P, Col NF, Ropka M, Collyar D, Morrow M, Runowicz C, Pritchard KI, Hagerty K, Arun B, Garber J, Vogel VG, Wade JL, Brown P, Cuzick J, Kramer BS, Lippman SM, Anonymous00092. · Cancer Policy and Clinical Affairs, 2318 Mill Rd, Suite 800, Alexandria, VA 22314, USA. · J Clin Oncol. · Pubmed #19470930 No free full text.
Abstract: PURPOSE To update the 2002 American Society of Clinical Oncology guideline on pharmacologic interventions for breast cancer (BC) risk reduction. METHODS A literature search identified relevant randomized trials published since 2002. Primary outcome of interest was BC incidence (invasive and noninvasive). Secondary outcomes included BC mortality, adverse events, and net health benefits. An expert panel reviewed the literature and developed updated consensus guidelines. Results Seventeen articles met inclusion criteria. In premenopausal women, tamoxifen for 5 years reduces the risk of BC for at least 10 years, particularly estrogen receptor (ER) -positive invasive tumors. Women < or = 50 years of age experience fewer serious side effects. Vascular and vasomotor events do not persist post-treatment across all ages. In postmenopausal women, raloxifene and tamoxifen reduce the risk of ER-positive invasive BC with equal efficacy. Raloxifene is associated with a lower risk of thromboembolic disease, benign uterine conditions, and cataracts than tamoxifen in postmenopausal women. No evidence exists establishing whether a reduction in BC risk from either agent translates into reduced BC mortality. Recommendations In women at increased risk for BC, tamoxifen (20 mg/d for 5 years) may be offered to reduce the risk of invasive ER-positive BC, with benefits for at least 10 years. In postmenopausal women, raloxifene (60 mg/d for 5 years) may also be considered. Use of aromatase inhibitors, fenretinide, or other selective estrogen receptor modulators to lower BC risk is not recommended outside of a clinical trial. Discussion of risks and benefits of preventive agents by health providers is critical to patient decision making.
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Review Using microarrays to study the microenvironment in tumor biology: the crucial role of statistics. free! 2008
Baker SG, Kramer BS. · Division of Cancer Prevention, National Cancer Institute, Bethesda, MD 20892-7354, USA. · Semin Cancer Biol. · Pubmed #18455427 links to free full text
Abstract: Microarrays represent a potentially powerful tool for better understanding the role of the microenvironment on tumor biology. To make the best use of microarray data and avoid incorrect or unsubstantiated conclusions, care must be taken in the statistical analysis. To illustrate the statistical issues involved we discuss three microarray studies related to the microenvironment and tumor biology involving: (i) prostatic stroma cells in cancer and non-cancer tissues; (ii) breast stroma and epithelial cells in breast cancer patients and non-cancer patients; and (iii) serum associated with wound response and stroma in cancer patients. Using these examples we critically discuss three types of analyses: differential gene expression, cluster analysis, and class prediction. We also discuss design issues.
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Review Cancer screening. 2000
Kramer BS, Brawley OW. · Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland, USA. · Hematol Oncol Clin North Am. · Pubmed #10949776 No free full text.
Abstract: Especially in the emotionally charged field of cancer screening, which can have substantial public health implications for large numbers of healthy, asymptomatic people, it is important to achieve strong levels of evidence before promulgating new screening tools. This review of screening study methodology is intended to help the reader weigh such evidence and to evaluate reports which appear in the literature. It is an attempt to go beyond the often-stated intuition that early cancer detection finds cancers when they are easier to treat, at a time when survival is best. Examples tell us that sometimes this assumption has been true, sometimes not. A familiarity with the hidden biases in the supposition can be translated into everyday medical practice for screening tests in general. The practitioner can then match the strength of recommendation with the strength of the evidence behind the recommendation.
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Article Early reporting for cancer screening trials. free! 2008
Baker SG, Kramer BS, Prorok PC. · Division of Cancer Prevention, National Cancer Institute, Bethesda, MD 20892-7354, USA. · J Med Screen. · Pubmed #18927094 links to free full text
Abstract: OBJECTIVE: Many cancer screening trials involve a screening programme of one or more screenings with follow-up after the last screening. Usually a maximum follow-up time is selected in advance. However, during the follow-up period there is an opportunity to report the results of the trial sooner than planned. Early reporting of results from a randomized screening trial is important because obtaining a valid result sooner translates into health benefits reaching the general population sooner. The health benefits are reduction in cancer deaths if screening is found to be beneficial and more screening is recommended, or avoidance of unnecessary biopsies, work-ups and morbidity if screening is not found to be beneficial and the rate of screening drops. METHODS: Our proposed method for deciding if results from a cancer screening trial should be reported earlier in the follow-up period is based on considerations involving postscreening noise. Postscreening noise (sometimes called dilution) refers to cancer deaths in the follow-up period that could not have been prevented by screening: (1) cancer deaths in the screened group that occurred after the last screening in subjects whose cancers were not detected during the screening program and (2) cancer deaths in the control group that occurred after the time of the last screening and whose cancers would not have been detected during the screening programme had they been randomized to screening (the number of which is unobserved). Because postscreening noise increases with follow-up after the last screening, we propose early reporting at the time during the follow-up period when postscreening noise first starts to overwhelm the estimated effect of screening as measured by a z-statistic. This leads to a confidence interval, adjusted for postscreening noise, that would not change substantially with additional follow-up. Details of the early reporting rule were refined by simulation, which also accounts for multiple looks. RESULTS: For the re-analysis of the Health Insurance Plan trial for breast cancer screening and the Mayo Lung Project for lung cancer screening, estimates and confidence intervals for the effect of screening on cancer mortality were similar on early reporting and later. CONCLUSION: The proposed early reporting rule for a cancer screening trial with post-screening follow-up is a promising method for making results from the trial available sooner, which translates into health benefits (reduction in cancer deaths or avoidance of unnecessary morbidity) reaching the population sooner.
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Article Clinical cancer advances 2007: major research advances in cancer treatment, prevention, and screening--a report from the American Society of Clinical Oncology. 2008
Gralow J, Ozols RF, Bajorin DF, Cheson BD, Sandler HM, Winer EP, Bonner J, Demetri GD, Curran W, Ganz PA, Kramer BS, Kris MG, Markman M, Mayer RJ, Raghavan D, Ramsey S, Reaman GH, Sawaya R, Schuchter LM, Sweetenham JW, Vahdat LT, Davidson NE, Schilsky RL, Lichter AS, Anonymous00362. · American Society of Clinical Oncology, 1900 Duke St, Suite 200, Alexandria, VA 22314, USA. · J Clin Oncol. · Pubmed #18086794 No free full text.
Abstract: A MESSAGE FROM ASCO'S PRESIDENT: For the third year, the American Society of Clinical Oncology (ASCO) is publishing Clinical Cancer Advances: Major Research Advances in Cancer Treatment, Prevention, and Screening, an annual review of the most significant cancer research presented or published over the past year. ASCO publishes this report to demonstrate the important progress being made on the front lines of clinical cancer research today. The report is intended to give all those with an interest in cancer care-the general public, cancer patients and organizations, policymakers, oncologists, and other medical professionals-an accessible summary of the year's most important cancer research advances. These pages report on the use of magnetic resonance imaging for breast cancer screening, the association between hormone replacement therapy and breast cancer incidence, the link between human papillomavirus and head and neck cancers, and the use of radiation therapy to prevent lung cancer from spreading. They also report on effective new targeted therapies for cancers that have been historically difficult to treat, such as liver cancer and kidney cancer, among many others. A total of 24 advances are featured in this year's report. These advances and many more over the past several years show that the nation's long-term investment in cancer research is paying off. But there are disturbing signs that progress could slow. We are now in the midst of the longest sustained period of flat government funding for cancer research in history. The budgets for the National Institutes of Health and the National Cancer Institute (NCI) have been unchanged for four years. When adjusted for inflation, cancer research funding has actually declined 12% since 2004. These budget constraints limit the NCI's ability to fund promising cancer research. In the past several years the number of grants that the NCI has been able to fund has significantly decreased; this year, in response to just the threat of a 10% budget cut, the nation's Clinical Trials Cooperative Groups reduced the number of patients participating in clinical trials by almost 2,000 and senior researchers report that many of the brightest young minds no longer see the promise of a career in science, choosing other careers instead. It's time to renew the nation's commitment to cancer research. Without additional support, the opportunity to build on the extraordinary progress to date will be lost or delayed. This report demonstrates the essential role that clinical cancer research plays in finding new and better ways to care for the more than 1.4 million people expected to be diagnosed with cancer this year. I want to thank the Editorial Board members, the Specialty Editors, and the ASCO Cancer Communications Committee for their dedicated work to develop this report. I hope you find it useful. Sincerely, Nancy E. Davidson, MD President American Society of Clinical Oncology.
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Article Clinical cancer advances 2006: major research advances in cancer treatment, prevention, and screening--a report from the American Society of Clinical Oncology. 2007
Ozols RF, Herbst RS, Colson YL, Gralow J, Bonner J, Curran WJ, Eisenberg BL, Ganz PA, Kramer BS, Kris MG, Markman M, Mayer RJ, Raghavan D, Reaman GH, Sawaya R, Schilsky RL, Schuchter LM, Sweetenham JW, Vahdat LT, Winn RJ, Anonymous00054. · American Society of Clinical Oncology, Alexandria, VA 22314, USA. · J Clin Oncol. · Pubmed #17158528 No free full text.
Abstract: A MESSAGE FROM ASCO's PRESIDENT For the second consecutive year, the American Society of Clinical Oncology (ASCO) is publishing Clinical Cancer Advances: Major Research Advances in Cancer Treatment, Prevention, and Screening, an annual review of the most significant cancer research presented or published over the past year. ASCO developed this report to demonstrate the enormous progress being made on the front lines of cancer research today. The report is intended to give all those with an interest in cancer care-the general public, cancer patients and physicians, policymakers, oncologists, and other medical professionals-an accessible summary of the year's most important cancer research advances. These pages report on new targeted therapies that are improving survival and response rates in hard-to-treat cancers such as kidney cancer, HER-2-positive breast cancer, head and neck cancer, and chronic myelogenous leukemia; the FDA's approval of the world's first preventive vaccine for human papillomavirus (HPV), which has the potential to dramatically reduce the global burden of cervical cancer; and advances in the fast-growing field of personalized medicine, including a new lung cancer test that could help physicians better target treatments and predict prognosis. These advances are only part of the landscape. Survival rates are on the rise, the number of cancer deaths in the United States began declining for the first time since 1930, and new research is showing that the rates of certain common cancers, such as those of the breast and colon, have stabilized, and may have even begun to decline. However, cancer research still faces a number of major obstacles. At a time of extraordinary scientific potential, declining federal funding of cancer research threatens to stall or even reverse recent progress. Such funding cuts have already led to fewer clinical trials, fewer talented young physicians entering the field, and a growing bottleneck of basic science discoveries waiting to be "translated" into useful therapies and diagnostics. In addition to highlighting the major research advances over the past year, this report also identifies key barriers to accelerating the pace of cancer research and outlines ASCO's recommendations for overcoming them. Despite these and other challenges, there is much good news on the front lines of cancer research. This report demonstrates the essential role of clinical cancer research in finding new and better ways to treat, diagnose, and prevent a group of diseases that strike half of men and one-third of women in the United States.
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Article Estimating the cumulative risk of a false-positive test in a repeated screening program. 2004
Xu JL, Fagerstrom RM, Prorok PC, Kramer BS. · Biometry Research Group, National Cancer Institute, Bethesda, Maryland 20892-7354, USA. · Biometrics. · Pubmed #15339287 No free full text.
Abstract: The goal of screening tests for a chronic disease such as cancer is early detection and treatment with a consequent reduction in mortality from the disease. Screening tests, however, might produce false positive and false-negative results. With an increasing number of screening tests, it is clear that the risk of a false-positive screen, a finding with potentially significant emotional, financial, and health costs, also increases. Elmore et al. (1998, New England Journal of Medicine 338, 1089-1096), Christiansen et al. (2000, Journal of the National Cancer Institute 92, 1657-1666), and Gelfand and Wang (2000, Statistics in Medicine 19, 1865-1879) investigated this problem under the somewhat unrealistic assumption that the choice of making the decision to drop out at the kth screen does not depend upon the results of the earlier k - 1 screens. In this article we obtain sufficient and necessary conditions for their assumption to hold and use one of them to provide a method for testing the validity of the assumption. A new model which does not depend on their assumption is introduced. The maximum likelihood estimator of the cumulative risk of receiving a false-positive screen under the new model is derived and its asymptotic normality is proved. The extension of the new model by incorporating covariate information is also considered. We apply our testing method and the new model to data from the breast cancer screening trial of the Health Insurance Plan of Greater New York.
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Article Comparing breast cancer mortality rates before-and-after a change in availability of screening in different regions: extension of the paired availability design. free! 2004
Baker SG, Kramer BS, Prorok PC. · Biometry Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, MD 20892-7354, USA. · BMC Med Res Methodol. · Pubmed #15149551 links to free full text
Abstract: BACKGROUND: In recent years there has been increased interest in evaluating breast cancer screening using data from before-and-after studies in multiple geographic regions. One approach, not previously mentioned, is the paired availability design. The paired availability design was developed to evaluate the effect of medical interventions by comparing changes in outcomes before and after a change in the availability of an intervention in various locations. A simple potential outcomes model yields estimates of efficacy, the effect of receiving the intervention, as opposed to effectiveness, the effect of changing the availability of the intervention. By combining estimates of efficacy rather than effectiveness, the paired availability design avoids confounding due to different fractions of subjects receiving the interventions at different locations. The original formulation involved short-term outcomes; the challenge here is accommodating long-term outcomes. METHODS: The outcome is incident breast cancer deaths in a time period, which are breast cancer deaths that were diagnosed in the same time period. We considered the plausibility of the basic five assumptions of the paired availability design and propose a novel analysis to accommodate likely violations of the assumption of stable screening effects. RESULTS: We applied the paired availability design to data on breast cancer screening from six counties in Sweden. The estimated yearly change in incident breast cancer deaths per 100,000 persons ages 40-69 (in most counties) due to receipt of screening (among the relevant type of subject in the potential outcomes model) was -9 with 95% confidence interval (-14, -4) or (-14, -5), depending on the sensitivity analysis. CONCLUSION: In a realistic application, the extended paired availability design yielded reasonably precise confidence intervals for the effect of receiving screening on the rate of incident breast cancer death. Although the assumption of stable preferences may be questionable, its impact will be small if there is little screening in the first time period. However, estimates may be substantially confounded by improvements in systemic therapy over time. Therefore the results should be interpreted with care.
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Article Estimating the cumulative risk of false positive cancer screenings. free! 2003
Baker SG, Erwin D, Kramer BS. · Biometry Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland, USA. · BMC Med Res Methodol. · Pubmed #12841854 links to free full text
Abstract: BACKGROUND: When evaluating cancer screening it is important to estimate the cumulative risk of false positives from periodic screening. Because the data typically come from studies in which the number of screenings varies by subject, estimation must take into account dropouts. A previous approach to estimate the probability of at least one false positive in n screenings unrealistically assumed that the probability of dropout does not depend on prior false positives. METHOD: By redefining the random variables, we obviate the unrealistic dropout assumption. We also propose a relatively simple logistic regression and extend estimation to the expected number of false positives in n screenings. RESULTS: We illustrate our methodology using data from women ages 40 to 64 who received up to four annual breast cancer screenings in the Health Insurance Program of Greater New York study, which began in 1963. Covariates were age, time since previous screening, screening number, and whether or not a previous false positive occurred. Defining a false positive as an unnecessary biopsy, the only statistically significant covariate was whether or not a previous false positive occurred. Because the effect of screening number was not statistically significant, extrapolation beyond 4 screenings was reasonable. The estimated mean number of unnecessary biopsies in 10 years per woman screened is.11 with 95% confidence interval of (.10,.12). Defining a false positive as an unnecessary work-up, all the covariates were statistically significant and the estimated mean number of unnecessary work-ups in 4 years per woman screened is.34 with 95% confidence interval (.32,.36). CONCLUSION: Using data from multiple cancer screenings with dropouts, and allowing dropout to depend on previous history of false positives, we propose a logistic regression model to estimate both the probability of at least one false positive and the expected number of false positives associated with n cancer screenings. The methodology can be used for both informed decision making at the individual level, as well as planning of health services.
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Article Reported family history of cancer in the prostate, lung, colorectal, and ovarian cancer screening trial. free! 2003
Pinsky PF, Kramer BS, Reding D, Buys S, Anonymous00351. · Division of Cancer Prevention, National Cancer Institute, Bethesda, MD 20892, USA. · Am J Epidemiol. · Pubmed #12727673 links to free full text
Abstract: The authors analyzed data from almost 150,000 subjects aged 55-74 years enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial who completed a self-administered baseline questionnaire (1993-2001) that included items about family history of cancer. Male respondents reported significantly less family history of cancer than females. The relative underreporting by male respondents relative to females was greater for female family members (28% lower for sisters and 21% lower for mothers) than for male family members (13% lower for brothers and 9% lower for fathers). Black, Hispanic, and Asian respondents reported significantly less family history of cancer than Whites. Reported family history prevalences for parents decreased with respondents' age, while those for siblings increased with respondents' age. The four most commonly reported cancers in families were breast (11.8%), lung (10.1%), colorectal (9.4%), and prostate (7.3%) cancer. Expected prevalences in family members of history of cancer overall and history of specific types of cancer were calculated using incidence rates and life table data obtained from the Surveillance, Epidemiology, and End Results Program. Overall, the ratio of reported cancer rates to expected cancer rates in family members was approximately 0.7. Liver, bone, stomach, and brain cancer had greater-than-average reported:expected ratios, while lymphoma, bladder cancer, melanoma, and testicular cancer had lower-than-average ratios.
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Article Using observational data to estimate an upper bound on the reduction in cancer mortality due to periodic screening. free! 2003
Baker SG, Erwin D, Kramer BS, Prorok PC. · Biometry Research Group, Division of Cancer Prevention, National Cancer Institute, USA. · BMC Med Res Methodol. · Pubmed #12689345 links to free full text
Abstract: BACKGROUND: Because randomized cancer screening trials are very expensive, observational cancer screening studies can play an important role in the early phases of screening evaluation. Periodic screening evaluation (PSE) is a methodology for estimating the reduction in population cancer mortality from data on subjects who receive regularly scheduled screens. Although PSE does not require assumptions about natural history of cancer it requires other assumptions, particularly progressive detection - the assumption that once a cancer is detected by a screening test, it will always be detected by the screening test. METHODS: We formulate a simple version of PSE and show that it leads to an upper bound on screening efficacy if the progressive detection assumption does not hold (and any effect of birth cohort is minimal) To determine if the upper bound is reasonable, for three randomized screening trials, we compared PSE estimates based only on screened subjects with PSE estimates based on all subjects. RESULTS: In the three randomized screening trials, PSE estimates based on screened subjects gave fairly close results to PSE estimates based on all subjects. CONCLUSION: PSE has promise for obtaining an upper bound on the reduction in population cancer mortality rates based on observational screening data. If the upper bound estimate is found to be small and any birth cohort effects are likely minimal, then a definitive randomized trial would not be warranted.
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Article Study design in the evaluation of breast cancer imaging technologies. 2000
Houn F, Bright RA, Bushar HF, Croft BY, Finder CA, Gohagan JK, Jennings RJ, Keegan P, Kessler LG, Kramer BS, Martynec LO, Robinowitz M, Sacks WM, Schultz DG, Wagner RF. · U.S. Food and Drug Administration, Rockville, MD 20852-0001, USA. · Acad Radiol. · Pubmed #10987329 No free full text.
Abstract: RATIONALE AND OBJECTIVES: Bringing a new imaging technology to market is a complex process. Beyond conceptualization and proof of concept, obtaining U.S. Food and Drug Administration (FDA) approval for clinical use depends on the documented experimental establishment of safety and efficacy. In turn, safety and efficacy are evaluated in the context of the intended use of the technology. The purpose of this study was to examine a conceptual framework for technology development and evaluation, focusing on new breast imaging technologies as a highly visible and current case in point. MATERIALS AND METHODS: The FDA views technology development in terms of a preclinical and four clinical phases of assessment. With a concept of research and development as a learning model, this phased-assessment concept of regulatory review against intended use was integrated with a five-level version of a hierarchy-of-efficacy framework for evaluating imaging technologies. Study design and analysis issues are presented in this context, as are approaches to supporting expanded clinical indications and new intended uses after a new technology is marketed. CONCLUSION: Breast imaging technologies may be intended for use as replacements for standard-of-care technologies, as adjuncts, or as complementary technologies. Study designs must be appropriate to establish claims of superiority or equivalence to the standard for the intended use. Screening technologies are ultimately judged on their demonstrated effectiveness in decreasing cause-specific mortality through early detection, but they may be brought to market for other uses on the basis of lesser standards of efficacy (eg, sensitivity, specificity, positive and negative predictive value, and stage of disease detected).
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