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Dive into the research topics where Jonathan D. Clapp is active.

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Featured researches published by Jonathan D. Clapp.


The New England Journal of Medicine | 2011

Reduced lung-cancer mortality with low-dose computed tomographic screening.

Denise R. Aberle; Amanda M. Adams; Christine D. Berg; William C. Black; Jonathan D. Clapp; Richard M. Fagerstrom; Ilana F. Gareen; Constantine Gatsonis; Pamela M. Marcus; JoRean D. Sicks

BACKGROUND The aggressive and heterogeneous nature of lung cancer has thwarted efforts to reduce mortality from this cancer through the use of screening. The advent of low-dose helical computed tomography (CT) altered the landscape of lung-cancer screening, with studies indicating that low-dose CT detects many tumors at early stages. The National Lung Screening Trial (NLST) was conducted to determine whether screening with low-dose CT could reduce mortality from lung cancer. METHODS From August 2002 through April 2004, we enrolled 53,454 persons at high risk for lung cancer at 33 U.S. medical centers. Participants were randomly assigned to undergo three annual screenings with either low-dose CT (26,722 participants) or single-view posteroanterior chest radiography (26,732). Data were collected on cases of lung cancer and deaths from lung cancer that occurred through December 31, 2009. RESULTS The rate of adherence to screening was more than 90%. The rate of positive screening tests was 24.2% with low-dose CT and 6.9% with radiography over all three rounds. A total of 96.4% of the positive screening results in the low-dose CT group and 94.5% in the radiography group were false positive results. The incidence of lung cancer was 645 cases per 100,000 person-years (1060 cancers) in the low-dose CT group, as compared with 572 cases per 100,000 person-years (941 cancers) in the radiography group (rate ratio, 1.13; 95% confidence interval [CI], 1.03 to 1.23). There were 247 deaths from lung cancer per 100,000 person-years in the low-dose CT group and 309 deaths per 100,000 person-years in the radiography group, representing a relative reduction in mortality from lung cancer with low-dose CT screening of 20.0% (95% CI, 6.8 to 26.7; P=0.004). The rate of death from any cause was reduced in the low-dose CT group, as compared with the radiography group, by 6.7% (95% CI, 1.2 to 13.6; P=0.02). CONCLUSIONS Screening with the use of low-dose CT reduces mortality from lung cancer. (Funded by the National Cancer Institute; National Lung Screening Trial ClinicalTrials.gov number, NCT00047385.).


The New England Journal of Medicine | 2009

Mortality Results from a Randomized Prostate-Cancer Screening Trial

Gerald L. Andriole; E. David Crawford; Robert L. Grubb; Saundra S. Buys; David Chia; Timothy R. Church; Mona N. Fouad; Edward P. Gelmann; Paul A. Kvale; Douglas J. Reding; Joel L. Weissfeld; Lance A. Yokochi; Jonathan D. Clapp; Joshua M. Rathmell; Thomas L. Riley; Richard B. Hayes; Barnett S. Kramer; Anthony B. Miller; Paul F. Pinsky; Philip C. Prorok; John K. Gohagan; Christine D. Berg

BACKGROUND The effect of screening with prostate-specific-antigen (PSA) testing and digital rectal examination on the rate of death from prostate cancer is unknown. This is the first report from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial on prostate-cancer mortality. METHODS From 1993 through 2001, we randomly assigned 76,693 men at 10 U.S. study centers to receive either annual screening (38,343 subjects) or usual care as the control (38,350 subjects). Men in the screening group were offered annual PSA testing for 6 years and digital rectal examination for 4 years. The subjects and health care providers received the results and decided on the type of follow-up evaluation. Usual care sometimes included screening, as some organizations have recommended. The numbers of all cancers and deaths and causes of death were ascertained. RESULTS In the screening group, rates of compliance were 85% for PSA testing and 86% for digital rectal examination. Rates of screening in the control group increased from 40% in the first year to 52% in the sixth year for PSA testing and ranged from 41 to 46% for digital rectal examination. After 7 years of follow-up, the incidence of prostate cancer per 10,000 person-years was 116 (2820 cancers) in the screening group and 95 (2322 cancers) in the control group (rate ratio, 1.22; 95% confidence interval [CI], 1.16 to 1.29). The incidence of death per 10,000 person-years was 2.0 (50 deaths) in the screening group and 1.7 (44 deaths) in the control group (rate ratio, 1.13; 95% CI, 0.75 to 1.70). The data at 10 years were 67% complete and consistent with these overall findings. CONCLUSIONS After 7 to 10 years of follow-up, the rate of death from prostate cancer was very low and did not differ significantly between the two study groups. (ClinicalTrials.gov number, NCT00002540.)


Journal of the National Cancer Institute | 2012

Prostate Cancer Screening in the Randomized Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial: Mortality Results after 13 Years of Follow-up

Gerald L. Andriole; E. David Crawford; Robert L. Grubb; Saundra S. Buys; David Chia; Timothy R. Church; Mona N. Fouad; Claudine Isaacs; Paul A. Kvale; Douglas J. Reding; Joel L. Weissfeld; Lance A. Yokochi; Barbara O’Brien; Lawrence R. Ragard; Jonathan D. Clapp; Joshua M. Rathmell; Thomas L. Riley; Ann W. Hsing; Grant Izmirlian; Paul F. Pinsky; Barnett S. Kramer; Anthony B. Miller; John K. Gohagan; Philip C. Prorok

BACKGROUND The prostate component of the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial was undertaken to determine whether there is a reduction in prostate cancer mortality from screening using serum prostate-specific antigen (PSA) testing and digital rectal examination (DRE). Mortality after 7-10 years of follow-up has been reported previously. We report extended follow-up to 13 years after the trial. METHODS A total of 76 685 men, aged 55-74 years, were enrolled at 10 screening centers between November 1993 and July 2001 and randomly assigned to the intervention (organized screening of annual PSA testing for 6 years and annual DRE for 4 years; 38 340 men) and control (usual care, which sometimes included opportunistic screening; 38 345 men) arms. Screening was completed in October 2006. All incident prostate cancers and deaths from prostate cancer through 13 years of follow-up or through December 31, 2009, were ascertained. Relative risks (RRs) were estimated as the ratio of observed rates in the intervention and control arms, and 95% confidence intervals (CIs) were calculated assuming a Poisson distribution for the number of events. Poisson regression modeling was used to examine the interactions with respect to prostate cancer mortality between trial arm and age, comorbidity status, and pretrial PSA testing. All statistical tests were two-sided. RESULTS Approximately 92% of the study participants were followed to 10 years and 57% to 13 years. At 13 years, 4250 participants had been diagnosed with prostate cancer in the intervention arm compared with 3815 in the control arm. Cumulative incidence rates for prostate cancer in the intervention and control arms were 108.4 and 97.1 per 10 000 person-years, respectively, resulting in a relative increase of 12% in the intervention arm (RR = 1.12, 95% CI = 1.07 to 1.17). After 13 years of follow-up, the cumulative mortality rates from prostate cancer in the intervention and control arms were 3.7 and 3.4 deaths per 10 000 person-years, respectively, resulting in a non-statistically significant difference between the two arms (RR = 1.09, 95% CI = 0.87 to 1.36). No statistically significant interactions with respect to prostate cancer mortality were observed between trial arm and age (P(interaction) = .81), pretrial PSA testing (P(interaction) = .52), and comorbidity (P(interaction) = .68). CONCLUSIONS After 13 years of follow-up, there was no evidence of a mortality benefit for organized annual screening in the PLCO trial compared with opportunistic screening, which forms part of usual care, and there was no apparent interaction with age, baseline comorbidity, or pretrial PSA testing.


JAMA | 2011

Effect of Screening on Ovarian Cancer Mortality: The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Randomized Controlled Trial

Saundra S. Buys; Edward E. Partridge; Amanda Black; Christine Cole Johnson; Lois Lamerato; Claudine Isaacs; Douglas J. Reding; Robert T. Greenlee; Lance A. Yokochi; Bruce Kessel; E. David Crawford; Timothy R. Church; Gerald L. Andriole; Joel L. Weissfeld; Mona N. Fouad; David Chia; Barbara O'Brien; Lawrence R. Ragard; Jonathan D. Clapp; Joshua M. Rathmell; Thomas L. Riley; Patricia Hartge; Paul F. Pinsky; Claire Zhu; Grant Izmirlian; Barnett S. Kramer; Anthony B. Miller; Jian Lun Xu; Philip C. Prorok; John K. Gohagan

CONTEXT Screening for ovarian cancer with cancer antigen 125 (CA-125) and transvaginal ultrasound has an unknown effect on mortality. OBJECTIVE To evaluate the effect of screening for ovarian cancer on mortality in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. DESIGN, SETTING, AND PARTICIPANTS Randomized controlled trial of 78,216 women aged 55 to 74 years assigned to undergo either annual screening (n = 39,105) or usual care (n = 39,111) at 10 screening centers across the United States between November 1993 and July 2001. Intervention The intervention group was offered annual screening with CA-125 for 6 years and transvaginal ultrasound for 4 years. Participants and their health care practitioners received the screening test results and managed evaluation of abnormal results. The usual care group was not offered annual screening with CA-125 for 6 years or transvaginal ultrasound but received their usual medical care. Participants were followed up for a maximum of 13 years (median [range], 12.4 years [10.9-13.0 years]) for cancer diagnoses and death until February 28, 2010. MAIN OUTCOME MEASURES Mortality from ovarian cancer, including primary peritoneal and fallopian tube cancers. Secondary outcomes included ovarian cancer incidence and complications associated with screening examinations and diagnostic procedures. RESULTS Ovarian cancer was diagnosed in 212 women (5.7 per 10,000 person-years) in the intervention group and 176 (4.7 per 10,000 person-years) in the usual care group (rate ratio [RR], 1.21; 95% confidence interval [CI], 0.99-1.48). There were 118 deaths caused by ovarian cancer (3.1 per 10,000 person-years) in the intervention group and 100 deaths (2.6 per 10,000 person-years) in the usual care group (mortality RR, 1.18; 95% CI, 0.82-1.71). Of 3285 women with false-positive results, 1080 underwent surgical follow-up; of whom, 163 women experienced at least 1 serious complication (15%). There were 2924 deaths due to other causes (excluding ovarian, colorectal, and lung cancer) (76.6 per 10,000 person-years) in the intervention group and 2914 deaths (76.2 per 10,000 person-years) in the usual care group (RR, 1.01; 95% CI, 0.96-1.06). CONCLUSIONS Among women in the general US population, simultaneous screening with CA-125 and transvaginal ultrasound compared with usual care did not reduce ovarian cancer mortality. Diagnostic evaluation following a false-positive screening test result was associated with complications. Trial Registration clinicaltrials.gov Identifier: NCT00002540.


Journal of the National Cancer Institute | 2010

Baseline Characteristics of Participants in the Randomized National Lung Screening Trial

Denise R. Aberle; Amanda M. Adams; Christine D. Berg; Jonathan D. Clapp; Kathy L. Clingan; Ilana F. Gareen; David A. Lynch; Pamela M. Marcus; Paul F. Pinsky

Background The National Lung Screening Trial (NLST), a randomized study conducted at 33 US sites, is comparing lung cancer mortality among persons screened with reduced dose helical computerized tomography and among persons screened with chest radiograph. In this article, we present characteristics of the study population. Methods Eligible participants were aged 55–74 years and were current or former smokers with a cigarette smoking history of at least 30 pack-years. Randomization was stratified by site, sex, and age. To assess representativeness of the study population, demographic characteristics of individuals from the general population who met NLST age and smoking history inclusion criteria were obtained from the Tobacco Use Supplement of the US Census Bureau Current Population Surveys. Results The NLST enrolled 53 456 persons, with 26 733 randomly assigned to chest radiograph screening and 26 723 to computerized tomography screening. Characteristics of the participants were as follows: 31 533 (59%) were men, 39 234 (73%) were younger than 65 years, 25 779 (48%) were current smokers, and 16 839 (32%) had a college or higher degree. Median cigarette exposure was 48 pack-years. Among Tobacco Use Supplement respondents who met NLST age and smoking history criteria, 59% were men, 65% were younger than 65 years, and 57% were current smokers. Median cigarette exposure among this group was 47 pack-years, and 14% had a college degree or higher. Conclusion The NLST cohort has a distribution of sex and pack-year history that is similar to the component of the general US population that meets the major NLST eligibility criteria; however, NLST participants are younger, better educated, and less likely to be current smokers.


Annals of Internal Medicine | 2010

Cumulative Incidence of False-Positive Test Results in Lung Cancer Screening: A Randomized Trial

Jennifer Croswell; Stuart G. Baker; Pamela M. Marcus; Jonathan D. Clapp; Barnett S. Kramer

BACKGROUND Direct-to-consumer promotion of lung cancer screening has increased, especially low-dose computed tomography (CT). However, screening exposes healthy persons to potential harms, and cumulative false-positive rates for low-dose CT have never been formally reported. OBJECTIVE To quantify the cumulative risk that a person who participated in a 1- or 2-year lung cancer screening examination would receive at least 1 false-positive result, as well as rates of unnecessary diagnostic procedures. DESIGN Randomized, controlled trial of low-dose CT versus chest radiography. (ClinicalTrials.gov registration number: NCT00006382) SETTING Feasibility study for the ongoing National Lung Screening Trial. PATIENTS Current or former smokers, aged 55 to 74 years, with a smoking history of 30 pack-years or more and no history of lung cancer (n = 3190). INTERVENTION Random assignment to low-dose CT or chest radiography with baseline and 1 repeated annual screening; 1-year follow-up after the final screening. Randomization was centralized and stratified by age, sex, and study center. MEASUREMENTS False-positive screenings, defined as a positive screening with a completed negative work-up or 12 months or more of follow-up with no lung cancer diagnosis. RESULTS By using a Kaplan-Meier analysis, a persons cumulative probability of 1 or more false-positive low-dose CT examinations was 21% (95% CI, 19% to 23%) after 1 screening and 33% (CI, 31% to 35%) after 2. The rates for chest radiography were 9% (CI, 8% to 11%) and 15% (CI, 13% to 16%), respectively. A total of 7% of participants with a false-positive low-dose CT examination and 4% with a false-positive chest radiography had a resulting invasive procedure. LIMITATIONS Screening was limited to 2 rounds. Follow-up after the second screening was limited to 12 months. The false-negative rate is probably an underestimate. CONCLUSION Risks for false-positive results on lung cancer screening tests are substantial after only 2 annual examinations, particularly for low-dose CT. Further study of resulting economic, psychosocial, and physical burdens of these methods is warranted. PRIMARY FUNDING SOURCE National Cancer Institute.


Annals of Family Medicine | 2009

Cumulative incidence of false-positive results in repeated, multimodal cancer screening

Jennifer Croswell; Barnett S. Kramer; Aimée R. Kreimer; Phil C. Prorok; Jian Lun Xu; Stuart G. Baker; Richard M. Fagerstrom; Thomas L. Riley; Jonathan D. Clapp; Christine D. Berg; John K. Gohagan; Gerald L. Andriole; David Chia; Timothy R. Church; E. David Crawford; Mona N. Fouad; Edward P. Gelmann; Lois Lamerato; Douglas J. Reding; Robert E. Schoen

PURPOSE Multiple cancer screening tests have been advocated for the general population; however, clinicians and patients are not always well-informed of screening burdens. We sought to determine the cumulative risk of a false-positive screening result and the resulting risk of a diagnostic procedure for an individual participating in a multimodal cancer screening program. METHODS Data were analyzed from the intervention arm of the ongoing Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, a randomized controlled trial to determine the effects of prostate, lung, colorectal, and ovarian cancer screening on disease-specific mortality. The 68,436 participants, aged 55 to 74 years, were randomized to screening or usual care. Women received serial serum tests to detect cancer antigen 125 (CA-125), transvaginal sonograms, posteroanterior-view chest radiographs, and flexible sigmoidoscopies. Men received serial chest radiographs, flexible sigmoidoscopies, digital rectal examinations, and serum prostate-specific antigen tests. Fourteen screening examinations for each sex were possible during the 3-year screening period. RESULTS After 14 tests, the cumulative risk of having at least 1 false-positive screening test is 60.4% (95% CI, 59.8%–61.0%) for men, and 48.8% (95% CI, 48.1%–49.4%) for women. The cumulative risk after 14 tests of undergoing an invasive diagnostic procedure prompted by a false-positive test is 28.5% (CI, 27.8%–29.3%) for men and 22.1% (95% CI, 21.4%–22.7%) for women. CONCLUSIONS For an individual in a multimodal cancer screening trial, the risk of a false-positive finding is about 50% or greater by the 14th test. Physicians should educate patients about the likelihood of false positives and resulting diagnostic interventions when counseling about cancer screening.


Journal of Clinical Oncology | 2014

Cognitive Impairment in Older Patients With Breast Cancer Before Systemic Therapy: Is There an Interaction Between Cancer and Comorbidity?

Jeanne S. Mandelblatt; Robert A. Stern; Gheorghe Luta; Meghan McGuckin; Jonathan D. Clapp; Arti Hurria; Paul B. Jacobsen; Leigh Anne Faul; Claudine Isaacs; Neelima Denduluri; Brandon E. Gavett; Tiffany A. Traina; Patricia Lynn Johnson; Rebecca A. Silliman; R. Scott Turner; Darlene V. Howard; John W. Van Meter; Andrew J. Saykin; Tim A. Ahles

PURPOSE To determine if older patients with breast cancer have cognitive impairment before systemic therapy. PATIENTS AND METHODS Participants were patients with newly diagnosed nonmetastatic breast cancer and matched friend or community controls age > 60 years without prior systemic treatment, dementia, or neurologic disease. Participants completed surveys and a 55-minute battery of 17 neuropsychological tests. Biospecimens were obtained for APOE genotyping, and clinical data were abstracted. Neuropsychological test scores were standardized using control means and standard deviations (SDs) and grouped into five domain z scores. Cognitive impairment was defined as any domain z score two SDs below or ≥ two z scores 1.5 SDs below the control mean. Multivariable analyses evaluated pretreatment differences considering age, race, education, and site; comparisons between patient cases also controlled for surgery. RESULTS The 164 patient cases and 182 controls had similar neuropsychological domain scores. However, among patient cases, those with stage II to III cancers had lower executive function compared with those with stage 0 to I disease, after adjustment (P = .05). The odds of impairment were significantly higher among older, nonwhite, less educated women and those with greater comorbidity, after adjustment. Patient case or control status, anxiety, depression, fatigue, and surgery were not associated with impairment. However, there was an interaction between comorbidity and patient case or control status; comorbidity was strongly associated with impairment among patient cases (adjusted odds ratio, 8.77; 95% CI, 2.06 to 37.4; P = .003) but not among controls (P = .97). Only diabetes and cardiovascular disease were associated with impairment among patient cases. CONCLUSION There were no overall differences between patients with breast cancer and controls before systemic treatment, but there may be pretreatment cognitive impairment within subgroups of patient cases with greater tumor or comorbidity burden.


Journal of Clinical Oncology | 2014

Frailty and Adherence to Adjuvant Hormonal Therapy in Older Women With Breast Cancer: CALGB Protocol 369901

Vanessa B. Sheppard; Leigh Anne Faul; George Luta; Jonathan D. Clapp; Rachel L. Yung; Judy Huei-yu Wang; Gretchen Kimmick; Claudine Isaacs; Michelle Tallarico; William T. Barry; Brandelyn N. Pitcher; Clifford A. Hudis; Harvey J. Cohen; Hyman B. Muss; Arti Hurria; Jeanne S. Mandelblatt

PURPOSE Most patients with breast cancer age ≥ 65 years (ie, older patients) are eligible for adjuvant hormonal therapy, but use is not universal. We examined the influence of frailty on hormonal therapy noninitiation and discontinuation. PATIENTS AND METHODS A prospective cohort of 1,288 older women diagnosed with invasive, nonmetastatic breast cancer recruited from 78 sites from 2004 to 2011 were included (1,062 had estrogen receptor-positive tumors). Interviews were conducted at baseline, 6 months, and annually for up to 7 years to collect sociodemographic, health care, and psychosocial data. Hormonal initiation was defined from records and discontinuation from self-report. Baseline frailty was measured using a previously validated 35-item scale and grouped as prefrail or frail versus robust. Logistic regression and proportional hazards models were used to assess factors associated with noninitiation and discontinuation, respectively. RESULTS Most women (76.4%) were robust. Noninitiation of hormonal therapy was low (14%), but in prefrail or frail (v robust) women the odds of noninitiation were 1.63 times as high (95% CI, 1.11 to 2.40; P = .013) after covariate adjustment. Nonwhites (v whites) had higher odds of noninitiation (odds ratio, 1.71; 95% CI, 1.04 to 2.80; P = .033) after covariate adjustment. Among initiators, the 5-year continuation probability was 48.5%. After adjustment, the risk of discontinuation was higher with increasing age (P = .005) and lower for stage ≥ IIB (v stage I) disease (P = .003). CONCLUSION Frailty is associated with noninitiation of hormonal therapy, but it does not seem to be a major predictor of early discontinuation in older patients.


Psycho-oncology | 2017

Personality, coping, and social support as predictors of long‐term quality‐of‐life trajectories in older breast cancer survivors: CALGB protocol 369901 (Alliance)

Estrella Durá-Ferrandis; Jeanne S. Mandelblatt; Jonathan D. Clapp; George Luta; LeighAnne Faul; Gretchen Kimmick; Harvey J. Cohen; Rachel L. Yung; Arti Hurria

To determine long‐term quality‐of‐life (QOL) trajectories among breast cancer survivors aged 65+ (older) evaluating the effects of personality and social support.

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Arti Hurria

City of Hope National Medical Center

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Barnett S. Kramer

National Institutes of Health

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Hyman B. Muss

University of North Carolina at Chapel Hill

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David Chia

University of California

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E. David Crawford

University of Colorado Denver

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