Recruitment in the prostate, lung, colorectal, and ovarian (PLCO) cancer screening trial: the first phase of recruitment at Henry Ford Health System

Influence of air quality on lung cancer in people who have never smoked

OBJECTIVE

Lung cancer is the leading cause of cancer-related death. The percentage of people who have never smoked with lung cancer has risen recently, but alternative risk factors require further study. Our goal was to determine the influence of air quality on incidence of lung cancer in people who have smoked or never smoked.

METHODS

The cancer registry from a large urban medical center was queried to include every new diagnosis of lung cancer from 2013 to 2021. Air quality and pollution data for the county were obtained from the US Environmental Protection Agency from 1980 to 2018. Patient demographics, location of residence, smoking history, and tumor stage were recorded. Bivariate comparison analyses were conducted in R (R Foundation for Statistical Computing).

RESULTS

A total of 2223 new cases of lung cancer were identified. Mean age was 69.2 years. There was a nonsmoking rate of 8.1%. A total of 37% of patients identified as a racial minority. People who have never smoked were more likely to be diagnosed at an advanced stage. When analyzing geographic distribution, incidence of lung cancer among people who have never smoked was more closely associated with highly polluted areas. People who have never smoked with lung cancer had significantly higher exposure levels of multiple pollutants.

CONCLUSIONS

Newly diagnosed lung cancer appears to be more related to poor air quality among people who have never smoked than people who have smoked. Future studies are needed to examine the associations of specific pollutants with lung cancer incidence.

Community Engagement Strategies for Underrepresented Racial and Ethnic Populations

The representation of racial and ethnic minority populations in clinical trials continues to be a challenge despite mandates, good intentions, and concerted efforts by funding agencies, regulatory bodies, and researchers to close the clinical trials gap. A lack of diversity in research results in both continued disparities and poorer health outcomes. It is thus imperative that investigators understand and effectively address the challenges of clinical trials participation by underrepresented populations. In this paper, we expound on best practices for participatory research by clearly defining the community, highlighting the importance of proper identification and engagement of strong community partners, and exploring patient- and provider-level barriers and facilitators that require consideration. A clearer understanding of the balance of power between researchers and community partners is needed for any approach that addresses clinical trials representation. Unintended biases in study design and methods may continue to prevent racial and ethnic minority participants from taking part, and significant organizational changes are necessary for efficient and transparent relationships. Comprehensive community engagement in research includes dissemination of clinical trial results within and in partnership with community partners. Through careful deliberation and honest reflection, investigators, institutions, and community partners can develop the tailored blueprints of research collaborations essential for true equity in clinical trials.

Design and virtual implementation of a biomedical registry framework for the enhancement of clinical trials: colorectal cancer example

Introduction

Clinical trials generate a large volume of literature and a vast amount of data. Following the 'open science' model, data sharing has enormous potential to strengthen scientific research. Currently, to the best of our knowledge, there is no existing web based Hellenic biomedical registry that displays available patients for clinical trials, providing direct access to registered physicians to all data, assisting them in finding eligible patients in the initial clinical trial recruitment process.

Methods

This paper describes the design and virtual implementation of a web based prototype biomedical registry in Greece. The system represents an eGovernment framework proposal for the central storage of patients' biomedical information and the operations associated with this process. The increasing tendency to include molecular data as prerequisite elements in clinical trials is adopted in the registry philosophy. The designed system is based on free, open source software and it is implemented virtually on a local host environment.

Results

Using colorectal cancer as an example, valid data from patients increases the reliability index, demonstrating the functionality of the web application.

Conclusion

In conclusion, the combination of biomedical data and information technology in order to display potential participants per health unit, facilitates recruitment for clinical trials.

The potential impact of chronic obstructive pulmonary disease in lung cancer screening: implications for the screening clinic

Introduction: Following the findings of the National Lung Screening Trial (NLST), lung cancer screening is now recommended in the United States. However, post-hoc analyses of the NLST suggest that reducing lung cancer mortality through screening is highly dependent on the underlying characteristics of the screening participants, in particular, the presence of chronic obstructive pulmonary disease (COPD). Areas covered: In this review, we outline how outcomes in lung cancer screening are significantly affected by the presence of airflow limitation, as caused by COPD, and how this might impact the assessment of eligible smokers in a lung cancer screening clinic. Expert opinion: There is growing evidence showing that CT-based screening for lung cancer reduces lung cancer mortality. The benefits of screening exceed those seen in the NLST when screening is carried out in lower risk populations, for a longer duration, and when outcomes are compared with usual care control cohorts. In this article, we review data from a post-hoc analysis of the NLST. We suggest that whilst worsened airflow limitation is associated with greater lung cancer risk, there is also more aggressive lung cancer, reduced lung cancer operability, and for advanced COPD, reduced benefits from screening. We advocate an 'outcomes-based' approach to screening over a 'risk-based' approach.

Chronic obstructive pulmonary disease (COPD) and lung cancer screening

The primary aim of lung cancer screening is to improve survival from lung cancer by identifying early stage non-small cell lung cancers and prolong survival through their surgical removal. In a post-hoc analysis of 10,054 screening participants from the National Lung Screening Trial (NLST) we show that the risk of lung cancer, according to the PLCOm2012 model, is closely related to the likelihood of having chronic obstructive pulmonary disease (COPD). Those at greatest risk for lung cancer have the highest prevalence of COPD and greater likelihood of dying of a non-lung cancer cause. This "competing cause of death" effect occurs because smokers eligible for lung cancer screening have a high prevalence of comorbid disease and greater likelihood of dying from cardiovascular disease, respiratory disease or other cancers. This means high risk smokers at greatest risk of lung cancer may not necessarily benefit from screening due to greater inoperability and premature death. In this analysis we show that the benefit of annual computed tomography (CT) screening is greatest in those with normal lung function or only mild-to-moderate COPD. We found no mortality benefit in those with severe or very severe COPD (GOLD 3-4). We also show that the efficiency of screening, based on optimizing the number of lung cancer deaths averted per 1,000 persons screened, is best achieved by screening those at intermediate risk. By combining clinical risk variables with a gene-based risk score, even greater reductions in lung cancer mortality can be achieved with CT. We suggest a biomarker-led outcomes-based approach may help to better define which eligible smokers might defer screening (low risk of lung cancer), discontinue screening (high risk of overtreatment with little benefit) or continue screening to achieve the greatest reduction in lung cancer mortality.

Feasibility of self-collection of fecal specimens by randomly sampled women for health-related studies of the gut microbiome

BACKGROUND

The field of microbiome research is growing rapidly. We developed a method for self-collection of fecal specimens that can be used in population-based studies of the gut microbiome. We conducted a pilot study to test the feasibility of our methods among a random sample of healthy, postmenopausal women who are members of Kaiser Permanente Colorado (KPCO). We aimed to collect questionnaire data, fecal and urine specimens from 60 women, aged 55-69, who recently had a normal screening mammogram. We designed the study such that all questionnaire data and specimens could be collected at home.

RESULTS

We mailed an invitation packet, consent form and opt-out postcard to 300 women, then recruited by telephone women who did not opt-out. Verbally consented women were mailed an enrollment package including a risk factor questionnaire, link to an online diet questionnaire, specimen collection kit, and instructions for collecting stool and urine. Specimens were shipped overnight to the biorepository. Of the 300 women mailed an invitation packet, 58 (19%) returned the opt-out postcard. Up to 3 attempts were made to telephone the remaining women, of whom 130 (43%) could not be contacted, 23 (8%) refused, and 12 (4%) were ineligible. Enrollment packages were mailed to 77 women, of whom 59 returned the risk factor questionnaire and specimens. We found no statistically significant differences between enrolled women and those who refused participation or could not be contacted.

CONCLUSIONS

We demonstrated that a representative sample of women can be successfully recruited for a gut microbiome study; however, significant personal contact and carefully timed follow-up from the study personnel are required. The methods employed by our study could successfully be applied to analytic studies of a wide range of clinical conditions that have been postulated to be influenced by the gut microbial population.

Uniting postcolonial, discourse, and linguistic theory to explore participation of African Americans in cancer research as an effect of social and historical race relationships

This article uses a historical framework of postcolonialism; discourse analytic concepts (significance, identity, and relationships); and 5 social and cultural linguistic principles of emergence, positionality, indexicality, relationality, and partialness as a theoretical and methodological triangulation approach to data analysis of focus group discussion. Exemplars of focus group data from a study exploring African American participation in research demonstrate the application of this combined framework as a useful tool for analysis. This approach allows for examination of identity and interaction and generates a more rigorous and complete understanding of how individuals use language to construct identity as participants or nonparticipants in research.

Nonparticipation in a population-based trial to increase colorectal cancer screening

BACKGROUND

Many trials have tested different strategies to increase colorectal cancer (CRC) screening. Few describe whether participants are representative of the population from which they are recruited.

PURPOSE

To determine risk factors related to nonparticipation among patients enrolled in an integrated health plan and not up to date for CRC testing, in a trial to increase screening rates.

METHODS

Between July 2008 and October 2009, a total of 15,000 adults aged 50-74 years from 21 clinics in Washington State who were due for CRC screening were contacted. Nonparticipants were defined as English-speaking patients who did not engage in the call or refused participation while still potentially eligible. Log-binomial regression models were used to estimate the relative risk of nonparticipation. Analyses were completed between October 2010 and June 2011.

RESULTS

Patients who were nonwhite, had less education, used tobacco, had less continuity of care, and had lower rates of preventive care and cancer screening were more likely to be nonparticipants. Patients reporting never having received any type of CRC testing or screening were also more likely not to participate (62% of nonparticipants vs 46% of participants; adjusted RR=1.58, 95% CI=1.47, 1.70). Reasons for refusal included costs, risks of procedures, and not wanting their medical records reviewed.

CONCLUSIONS

Patients eligible for but not participating in the trial were more likely to be from minority socioeconomic and racial groups and had behaviors that can negatively affect cancer outcomes. Additional efforts are needed to recruit patients who need CRC screening the most.

TRIAL REGISTRATION

This trial is registered at clinicaltrials.gov NCT 00697047.

A population-based cohort study of chest x-ray screening in smokers: lung cancer detection findings and follow-up

BACKGROUND

Case-control studies of mass screening for lung cancer (LC) by chest x-rays (CXR) performed in the 1990s in scarcely defined Japanese target populations indicated significant mortality reductions, but these results are yet to be confirmed in western countries. To ascertain whether CXR screening decreases LC mortality at community level, we studied a clearly defined population-based cohort of smokers invited to screening. We present here the LC detection results and the 10-year survival rates.

METHODS

The cohort of all smokers of > 10 pack-years resident in 50 communities of Varese, screening-eligible (n = 5,815), in July 1997 was invited to nonrandomized CXR screening. Self-selected participants (21% of cohort) underwent screening in addition to usual care; nonparticipants received usual care. The cohort was followed-up until December 2010. Kaplan-Meier LC-specific survival was estimated in participants, in nonparticipants, in the whole cohort, and in an uninvited, unscreened population (control group).

RESULTS

Over the initial 9.5 years of study, 67 LCs were diagnosed in screening participants (51% were screen-detected) and 178 in nonparticipants. The rates of stage I LC, resectability and 5-year survival were nearly twice as high in participants (32% stage I; 48% resected; 30.5% 5-year survival) as in nonparticipants (17% stage I; 27% resected; 13.5% 5-year survival). There were no bronchioloalveolar carcinomas among screen-detected cancers, and median volume doubling time of incidence screen-detected LCs was 80 days (range, 44-318), suggesting that screening overdiagnosis was minimal. The 10-year LC-specific survival was greater in screening participants than in nonparticipants (log-rank, p = 0.005), and greater in the whole cohort invited to screening than in the control group (log-rank, p = 0.001). This favourable long-term effect was independently related to CXR screening exposure.

CONCLUSION

In the setting of CXR screening offered to a population-based cohort of smokers, screening participants who were diagnosed with LC had more frequently early-stage resectable disease and significantly enhanced long-term LC survival. These results translated into enhanced 10-year LC survival, independently related to CXR screening exposure, in the entire population-based cohort. Whether increased long-term LC-specific survival in the cohort corresponds to mortality reduction remains to be evaluated.

TRIAL REGISTRATION NUMBER

ISRCTN90639073.

Process evaluation of recruitment for a cancer screening trial in primary care

Many cancer screening studies are conducted in primary care settings, yet few systematically analyze recruitment challenges found at these sites. During a randomized trial promoting colorectal cancer screening, we implemented a process evaluation of recruitment. Recruiters maintained logs that registered the numbers of patients entering the clinic, approached by recruiters, declining to participate, and reasons for nonapproach and nonparticipation. One half of age-eligible patients were approached (n = 1,489), and half of those who met basic eligibility requirements agreed to engage further (n = 527). A small proportion of patients (n = 98) completed the 15-min assessment before their appointment. Major reasons for nonapproach included previous approach, patients called to the exam room, and appearing ill. The major reason for nonparticipation was "not interested"; a few patients did not want to share contact information. Some participants exited the assessment midway because of further ineligibility or time limitations. Best-practice recommendations for recruitment in primary care are discussed.

Targeted prostate cancer screening in men with mutations in BRCA1 and BRCA2 detects aggressive prostate cancer: preliminary analysis of the results of the IMPACT study

OBJECTIVE

To evaluate the role of targeted prostate cancer screening in men with BRCA1 or BRCA2 mutations, an international study, IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls), was established. This is the first multicentre screening study targeted at men with a known genetic predisposition to prostate cancer. A preliminary analysis of the data is reported.

PATIENTS AND METHODS

Men aged 40-69 years from families with BRCA1 or BRCA2 mutations were offered annual prostate specific antigen (PSA) testing, and those with PSA > 3 ng/mL, were offered a prostate biopsy. Controls were men age-matched (± 5 years) who were negative for the familial mutation.

RESULTS

In total, 300 men were recruited (205 mutation carriers; 89 BRCA1, 116 BRCA2 and 95 controls) over 33 months. At the baseline screen (year 1), 7.0% (21/300) underwent a prostate biopsy. Prostate cancer was diagnosed in ten individuals, a prevalence of 3.3%. The positive predictive value of PSA screening in this cohort was 47·6% (10/21). One prostate cancer was diagnosed at year 2. Of the 11 prostate cancers diagnosed, nine were in mutation carriers, two in controls, and eight were clinically significant.

CONCLUSIONS

The present study shows that the positive predictive value of PSA screening in BRCA mutation carriers is high and that screening detects clinically significant prostate cancer. These results support the rationale for continued screening in such men.

Non-steroidal anti-inflammatory drug use and colorectal polyps in the Prostate, Lung, Colorectal, And Ovarian Cancer Screening Trial

OBJECTIVES

Non-steroidal anti-inflammatory drugs (NSAIDs) have been documented in animal and human studies to reduce risk for colorectal cancer and adenomatous polyps, but risk modification for subgroups of the population and effects on hyperplastic polyps have been less studied.

METHODS

Data on recent use of two frequently ingested NSAIDs, aspirin and ibuprofen, were collected at baseline from participants aged 55-74 years in the 10 centers of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). Participants randomized to the intervention arm of the trial received a flexible sigmoidoscopy during a baseline examination. Follow-up of detected polyps was accomplished outside the Trial setting and relevant records were sought and abstracted. Cases (n=4,017) included subjects with a biopsy-proven polyp in the left side of the colon (descending colon, sigmoid, and rectum) detected as a consequence of PLCO screening; controls (n=38,396) were subjects with no left-sided colon polyp.

RESULTS

Regular use of aspirin (≥ 4 times/month) in the past year was inversely associated with hyperplastic polyps (odds ratios (OR)=0.8, 95% confidence interval (CI)=0.7-0.9), adenomatous polyps (OR=0.8, 95% CI=0.8-0.9), and advanced adenomas (OR=0.8, 95% CI=0.7-0.9). As frequency of aspirin use increased, the prevalence of polyps decreased significantly for each histological classification (P for trend ≤ 0.0004). Similar patterns were found for adenomas and ibuprofen. Overall protection was consistent in both the descending colon or sigmoid and the rectum, but more evident in males. In males, the OR for heavy use of combined aspirin and ibuprofen (≥ 2 times/day) was 0.6 (95% CI=0.5-0.8), as opposed to 0.9 (95% CI=0.8-1.1) in females. The protective effects of NSAIDs for females were apparent only among those with body mass index (BMI) <25 (OR=0.8, 95% CI=0.7-1.0 for regular use of NSAIDs; P interaction=0.04). We also found a slightly stronger protection of NSAIDs in the 70-74 years age group compared with those aged 55-69 years.

CONCLUSIONS

This study of a large general risk population supports previous work that recent use of aspirin and ibuprofen is associated with a decreased risk of colorectal adenomas and demonstrates that this protective effect may be stronger in certain population subgroups and is also evident for aspirin and hyperplastic polyps.

The epidemiology of CA-125 in women without evidence of ovarian cancer in the Prostate, Lung, Colorectal and Ovarian Cancer (PLCO) Screening Trial

OBJECTIVE

To determine the epidemiology of CA-125 in women without ovarian cancer.

METHODS

We analyzed demographic, medical and lifestyle characteristics related to CA-125, measured using the Centocor CA-125II RIA assay, among 25,608 multi-ethnic U.S. women aged 55-74 years enrolled in a cancer screening trial and found to have no evidence of ovarian cancer.

RESULTS

Mean CA-125 level was 11.9 U/ml (SD 8.3); median 10.0 U/ml, interquartile range 8.0-14.0. High levels, using the clinical cut point of >or=35 U/ml, were associated with increased age (p<0.001) and former smoking (p<0.021), while hysterectomy and obesity were protective (p<0.001). Mean levels were higher with increasing age (p<0.001), ever use of hormone therapy (p<0.001), former smoking (p<0.017) and history of breast cancer (p<0.002), but lower (p<0.001) with non-White status, previous hysterectomy, current smoking, and obesity. Current hormone therapy use was not associated with CA-125 in women without a uterus.

CONCLUSION

In post-menopausal women without ovarian cancer, CA-125 level is influenced by a number of factors, including race/ethnicity, age, hysterectomy, smoking history and obesity.