Publications by authors named "PM Marcus"

Overdiagnosed cancers are those that are screen-detected but never would have been symptomatic during patients' lifetimes. Indolent cancers are overdiagnosed cancers. Non-indolent cancers can be overdiagnosed when patients die of causes other than the screen-detected cancer and would have, in the absence of screening, been asymptomatic and undiagnosed at the time of death.

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Numerous organizations, including the United States Preventive Services Task Force, recommend annual lung cancer screening (LCS) with low-dose CT for high risk adults who meet specific criteria. Despite recommendations and national coverage for screening eligible adults through the Centers for Medicare and Medicaid Services, LCS uptake in the United States remains low (<4%). In recognition of the need to improve and understand LCS across the population, as part of the larger Population-based Research to Optimize the Screening PRocess (PROSPR) consortium, the NCI (Bethesda, MD) funded the Lung PROSPR Research Consortium consisting of five diverse healthcare systems in Colorado, Hawaii, Michigan, Pennsylvania, and Wisconsin.

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The Lung Screening Study was a multicenter controlled feasibility trial that randomly assigned subjects to undergo two rounds of screening with either low-dose spiral computed tomography (LDCT) or chest X-ray (CXR). Long-term follow-up was performed to evaluate any differences in lung-cancer-specific and all-cause mortality between arms. In 2000, subjects were randomly assigned at six screening centers.

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Cancer screening tests have helped to reduce cancer deaths. We provide an overview of recent research pertaining to the definition, health impact, and prevalence of several screening tests. We also discuss the multilevel correlates and determinants of screening and interventions designed to increase uptake.

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Purposes: Despite recommendations against prostate cancer screening with prostate-specific antigen (PSA) tests, about one-fourth of men age ≥40 years received PSA tests in 2015. This study aimed to answer 3 questions for men who had a PSA test in the past year: (1) What percentage of these men received the test first suggested by physicians? (2) What factors were associated with physician-initiated PSA testing (PIPT) versus patient/someone else-initiated testing? (3) What percentage of patients ever had shared decision-making when tests were initiated by physicians?

Methods: We analyzed the 2000 and 2015 National Health Interview Survey data. We calculated age-standardized prevalence of PIPT for both years.

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Introduction: Recommendations for prostate-specific antigen-based screening for prostate cancer are placing increasing emphasis on men aged 55-69 years. The goal of the current study is to describe patterns of population-based prostate-specific antigen testing with details about that age group.

Methods: National Health Interview Surveys from 2005 to 2015 were analyzed in 2017 to estimate routine prostate-specific antigen testing in the past year from self-reported data by age group (40-54, 55-69, ≥70 years), and also by risk group, defined as African American men or men with a family history of prostate cancer versus other men.

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Precision medicine, an emerging approach for disease treatment that takes into account individual variability in genes, environment, and lifestyle, is under consideration for preventive interventions, including cancer screening. On September 29, 2015, the National Cancer Institute sponsored a symposium entitled "Precision Cancer Screening in the General Population: Evidence, Epidemiology, and Next Steps". The goal was two-fold: to share current information on the evidence, practices, and challenges surrounding precision screening for breast, cervical, colorectal, lung, and prostate cancers, and to allow for in-depth discussion among experts in relevant fields regarding how epidemiology and other population sciences can be used to generate evidence to inform precision screening strategies.

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Background/aims: Randomized controlled trials frequently use death review committees to assign a cause of death rather than relying on cause of death information from death certificates. The National Lung Screening Trial, a randomized controlled trial of lung cancer screening with low-dose computed tomography versus chest X-ray for heavy and/or long-term smokers ages 55-74 years at enrollment, used a committee blinded to arm assignment for a subset of deaths to determine whether cause of death was due to lung cancer.

Methods: Deaths were selected for review using a pre-determined computerized algorithm.

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Objective: To obtain information from participants in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial regarding their perception of the retention materials employed by the screening centers. Also, to determine the viability of using email or the internet as a data collection tool with an older population.

Design: Three of ten PLCO screening centers queried participants towards the end of the study (2010) as to their opinions of the various retention materials and whether they would have been willing to use electronic communication for study activities, had the option been available.

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Biomedical research cannot succeed without funding, knowledgeable staff, and appropriate infrastructure. There are however equally important but intangible factors that are rarely considered in planning large multidisciplinary endeavors or evaluating their success. The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial required extensive collaborations between individuals from many fields, including clinicians, clinical trialists, and administrators; it also addressed questions across the spectrum of cancer prevention and control.

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The most rigorous and accurate approach to evaluating clinical events in cancer screening studies is to use data obtained through medical record abstraction (MRA). Although MRA is complex, the particulars of the procedure-such as the specific training and quality assurance processes, challenges of implementation, and other factors that influence the quality of abstraction--are usually not described in reports of studies that employed the technique. In this paper, we present the details of MRA activities used in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, which used MRA to determine primary and secondary outcomes and collect data on other clinical events.

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It is imperative to measure the degree of contamination throughout the course of randomized controlled trials, as contamination, the receipt of the intervention arm regimen by control arm participants, can affect trial power. In the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, contamination was estimated through use of the self-administered Health Status Questionnaire (HSQ) annually to a randomly-selected subset of control arm participants. We examined agreement of self-report of chest x-ray on the HSQ with clinic records at one of the 10 PLCO screening centers (Henry Ford Health System, or HFHS).

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The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial was a large, randomized controlled trial of cancer screening that also evolved over time into a unique epidemiologic cohort. Vast quantities of data have been collected since the beginning of the trial in 1993. Screening data was obtained through 2006.

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Targeted cancer screening refers to use of disease risk information to identify those most likely to benefit from screening. Researchers have begun to explore the possibility of refining screening regimens for average-risk individuals using genetic and non-genetic risk factors and previous screening experience. Average-risk individuals are those not known to be at substantially elevated risk, including those without known inherited predisposition, without comorbidities known to increase cancer risk, and without previous diagnosis of cancer or pre-cancer.

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Background: It is unclear whether the higher rate of colorectal cancer (CRC) among non-Hispanic blacks (blacks) is due to lower rates of CRC screening or greater biologic risk.

Objective: We aimed to evaluate whether blacks are more likely than non-Hispanic whites (whites) to develop distal colon neoplasia (adenoma and/or cancer) after negative flexible sigmoidoscopy (FSG).

Design: We analyzed data of participants with negative FSGs at baseline in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial who underwent repeat FSGs 3 or 5 years later.

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The aim of cancer screening is to detect asymptomatic cancers whose treatment will result in extension of life, relative to length of life absent screening. Unfortunately, cancer screening also results in overdiagnosis, the detection of cancers that, in the absence of screening, would not present symptomatically during one's lifetime. Thus, their detection and subsequent treatment is unnecessary and detrimental.

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Background: The Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial provides us an opportunity to describe interval lung cancers not detected by screening chest X-ray (CXR) compared to screen-detected cancers.

Methods: Participants were screened for lung cancer with CXR at baseline and annually for two (never smokers) or three (ever smokers) more years. Screen-detected cancers were those with a positive CXR and diagnosed within 12 months.

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Objective: Identify predictors of non-compliance with first round screening exams in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

Method: The PLCO was conducted from 1993 to 2011 at 10 US institutions. A total of 154,897 healthy men and women ages 55-74 years were randomized.

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Background: The National Lung Screening Trial was conducted to determine whether three annual screenings (rounds T0, T1, and T2) with low-dose helical computed tomography (CT), as compared with chest radiography, could reduce mortality from lung cancer. We present detailed findings from the first two incidence screenings (rounds T1 and T2).

Methods: We evaluated the rate of adherence of the participants to the screening protocol, the results of screening and downstream diagnostic tests, features of the lung-cancer cases, and first-line treatments, and we estimated the performance characteristics of both screening methods.

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