Patients Diagnosed with Colorectal Cancer in Rural Areas in Arizona Typically Present with Higher Stage Disease

Statistical methods for measuring trends in colorectal cancer incidence in registries: A systematic review

Background

Monitoring cancer trends in a population is essential for tracking the disease’s burden, allocating resources, and informing public health policies. This review describes variations in commonly employed methods to estimate colorectal cancer (CRC) incidence trends.

Methods

We performed a systematic literature search in four databases to identify population-based studies reporting CRC incidence trends, published between January 2010 and May 2020. We extracted and described data on methods to estimate trends and assess model validity, and the software used.

Results

This review included 145 articles based on studies conducted in five continents. The majority (93%) presented visual summaries of trends combined with absolute, relative, or annual change estimates. Fourteen (10%) articles exclusively calculated the relative change in incidence over a given time interval, presented as the percentage of change in rates. Joinpoint regression analysis was the most commonly used method for assessing incidence trends (n= 65, 45%), providing estimates of the annual percentage change (APC) in rates. Nineteen (13%) studies performed Poisson regression and 18 (12%) linear regression analysis. Age-period-cohort modeling- a type of generalized linear models- was conducted in 18 (12%) studies. Thirty-nine (37%) of the studies modeling incidence trends (n=104, 72%) indicated the method used to evaluate model fitness. The joinpoint program (52%) was the statistical software most commonly used.

Conclusion

This review identified variation in the calculation of CRC incidence trends and inadequate reporting of model fit statistics. Our findings highlight the need for increasing clarity and transparency in reporting methods to facilitate interpretation, reproduction, and comparison with findings from previous studies.

Rural-Urban Disparities in Cancer Outcomes: Opportunities for Future Research

Cancer care disparities among rural populations are increasingly documented and may be worsening, likely because of the impact of rurality on access to state-of-the-art cancer prevention, diagnosis, and treatment services, as well as higher rates of risk factors such as smoking and obesity. In 2018, the American Society of Clinical Oncology undertook an initiative to understand and address factors contributing to rural cancer care disparities. A key pillar of this initiative was to identify knowledge gaps and promote the research needed to understand the magnitude of difference in outcomes in rural vs nonrural settings, the drivers of those differences, and interventions to address them. The purpose of this review is to describe continued knowledge gaps and areas of priority research to address them. We conducted a comprehensive literature review by searching the PubMed (Medline), Embase, Web of Science, and Cochrane Library databases for studies published in English between 1971 and 2021 and restricted to primary reports from populations in the United States and abstracted data to synthesize current evidence and identify continued gaps in knowledge. Our review identified continuing gaps in the literature regarding the underlying causes of rural-urban disparities in cancer outcomes. Rapid advances in cancer care will worsen existing disparities in outcomes for rural patients without directed effort to understand and address barriers to high-quality care in these areas. Research should be prioritized to address ongoing knowledge gaps about the drivers of rurality-based disparities and preventative and corrective interventions.

Influence of Race, Insurance, Rurality, and Socioeconomic Status on Equity of Lung and Colorectal Cancer Care

BACKGROUND

This study evaluated the influence that social determinants of health had on stage at diagnosis and receipt of cancer-directed surgery for patients with lung and colorectal cancer in the North Carolina Central Cancer Registry (2010-2015).

METHODS

This study examined non-Hispanic uninsured or privately-insured patients 18 to 64 years of age. Multivariable logistic regression models, including two-way interaction terms, assessed the influence of race, insurance status, rurality, and Social Deprivation Index on stage at diagnosis and receipt of surgery.

RESULTS

6574 lung cancer patients and 5355 colorectal cancer patients were included. Among the lung cancer patients, the uninsured patients had higher odds of having stage IV disease (odds ratio [OR] = 1.46; 95 % confidence interval [CI] = 1.22-1.76) and lower odds of receiving surgery (OR = 0.48; 95 % CI = 0.34-0.69) than the privately-insured patients. Among the colorectal cancer patients, uninsured status was associated with higher odds of stage IV disease (OR = 1.53; 95 % CI = 1.17-2.00) than privately-insured status. A significant insurance status and rurality interaction (p = 0.03) was found in the colorectal model for receipt of surgery. In the privately-insured group, non-Hispanic Black and rural patients had lower odds of receiving colorectal surgery (OR = 0.69; 95 % CI = 0.50-0.94 and OR = 0.68; 95 % CI = 0.52-0.89; respectively) than their non-Hispanic White and urban counterparts.

CONCLUSIONS

After controlling for confounding and evaluation of interactions between patient-, community-, and geographic-level factors, uninsured status remained the strongest driver of patients' presentation with late-stage lung and colorectal cancer. As policy and care delivery transformation targets uninsured and vulnerable populations, explicit recognition, and measurement of intersectionality should be considered.

A systematic review of methods to estimate colorectal cancer incidence using population-based cancer registries

Background

Epidemiological studies of incidence play an essential role in quantifying disease burden, resource planning, and informing public health policies. A variety of measures for estimating cancer incidence have been used. Appropriate reporting of incidence calculations is essential to enable clear interpretation. This review uses colorectal cancer (CRC) as an exemplar to summarize and describe variation in commonly employed incidence measures and evaluate the quality of reporting incidence methods.

Methods

We searched four databases for CRC incidence studies published between January 2010 and May 2020. Two independent reviewers screened all titles and abstracts. Eligible studies were population-based cancer registry studies evaluating CRC incidence. We extracted data on study characteristics and author-defined criteria for assessing the quality of reporting incidence. We used descriptive statistics to summarize the information.

Results

This review retrieved 165 relevant articles. The age-standardized incidence rate (ASR) (80%) was the most commonly reported incidence measure, and the 2000 U.S. standard population the most commonly used reference population (39%). Slightly more than half (54%) of the studies reported CRC incidence stratified by anatomical site. The quality of reporting incidence methods was suboptimal. Of all included studies: 45 (27%) failed to report the classification system used to define CRC; 63 (38%) did not report CRC codes; and only 20 (12%) documented excluding certain CRC cases from the numerator. Concerning the denominator estimation: 61% of studies failed to state the source of population data; 24 (15%) indicated census years; 10 (6%) reported the method used to estimate yearly population counts; and only 5 (3%) explicitly explained the population size estimation procedure to calculate the overall average incidence rate. Thirty-three (20%) studies reported the confidence interval for incidence, and only 7 (4%) documented methods for dealing with missing data.

Conclusion

This review identified variations in incidence calculation and inadequate reporting of methods. We outlined recommendations to optimize incidence estimation and reporting practices. There is a need to establish clear guidelines for incidence reporting to facilitate assessment of the validity and interpretation of reported incidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01632-7.

Influence of Race, Insurance, and Rurality on Equity of Breast Cancer Care

BACKGROUND

Considerable gaps in knowledge remain regarding the intersectionality between race, insurance status, rurality, and community-level socioeconomic status that contribute in concert to disparities in breast cancer care delivery.

METHODS

Women age 18-64 y old with either private, Medicaid, or no insurance coverage and a diagnosis of breast cancer from the North Carolina Central Cancer Registry (2010-2015) were identified and reviewed. Logistic regression models examined the impact of race, insurance status, rurality, and the Social Deprivation Index (SDI) on advanced stage disease at diagnosis (III, IV) and receipt of cancer directed surgery (CDS). Models tested two-way interactions between race, insurance status, rurality, and SDI.

RESULTS

Of the study population (n = 23,529), 14.6% were diagnosed with advanced stage disease (III, IV), and 97.1% of women with non-metastatic breast cancer (n = 22,438) received cancer directed surgery (CDS). Twenty percent of women were non-Hispanic Black (NHB), 3.0% Hispanic, 10.9% Medicaid insured, 5.9% uninsured, 20.0% of women resided in rural areas, and 20.0% resided in communities of the highest quartile SDI. NHB race, Medicaid or uninsured status, and residence in rural or socially deprived areas were associated with advanced stage breast cancer at diagnosis. NHB and Medicaid or uninsured women were significantly less likely to receive CDS. There were no statistically significant interactions found influencing stage at diagnosis or receipt of cancer directed surgery.

CONCLUSIONS

In a heterogeneous population across the state of North Carolina, non-Hispanic Black race, Medicaid or uninsured status, and residence in rural or high social deprivation communities are independently associated with advanced stage breast cancer at diagnosis, while non-Hispanic Black race and Medicaid or uninsured status are associated with lower odds to receive cancer directed surgery.

Improving Colorectal Cancer Screening in a Rural Setting: A Randomized Study

INTRODUCTION

Colorectal cancer screening has been shown to prevent or detect early colorectal cancer and reduce mortality; yet, adherence to screening recommendations remains low, particularly in rural settings.

STUDY DESIGN

RCT.

SETTING/PARTICIPANTS

Adults (n=7,812) aged 50-75 years and due for colorectal cancer screening in a largely rural health system were randomly assigned to either the intervention (n=3,906) or the control (n=3,906) group in September 2016, with analysis following through 2018.

INTERVENTION

A mailed motivational messaging screening reminder letter with an option to call and request a free at-home fecal immunochemical screening test (intervention) or the standard invitation letter detailing that the individual was due for screening (control). Multifaceted motivational messaging emphasized colorectal cancer preventability and the ease and affordability of screening, and communicated a limited supply of test kits.

MAIN OUTCOME MEASURES

Colorectal cancer screening participation within 6 months after mailed invitation was ascertained from the electronic medical record.

RESULTS

Colorectal cancer screening participation was significantly improved in the intervention (30.1%) vs the usual care control group (22.5%; p<0.001). Individuals randomized to the intervention group had 49% higher odds of being screened over follow-up than those randomized to the control group (OR=1.49, 95% CI=1.34, 1.65). A total of 13.2 screening invitations were needed to accomplish 1 additional screening over the usual care. Of the 233 fecal immunochemical test kits mailed to participants, 154 (66.1%) were returned, and 18 (11.7%) tested positive.

CONCLUSIONS

A mailed motivational messaging letter with a low-cost screening alternative increased colorectal cancer screening in this largely rural community with generally poor adherence to screening recommendations. Mailed colorectal cancer screening reminders using motivational messaging may be an effective method for increasing screening and reducing rural colorectal cancer disparities.

Investigating the Impact of Geographic Location on Colorectal Cancer Stage at Diagnosis: A National Study of the SEER Cancer Registry

BACKGROUND

Early detection of colorectal cancer (CRC) is associated with decreased mortality and potential avoidance of chemotherapy. CRC screening rates are lower in rural communities and patient outcomes are poorer. This study examines the extent to which United States' rural residents present at a more advanced stage of CRC compared to nonrural residents.

METHODS

Using the 2010-2014 Surveillance, Epidemiology and End Results Incidence data, 132,277 patients with CRC were stratified using their county of residence and urban influence codes into 5 categories (metro, adjacent micropolitan, nonadjacent micropolitan, small rural, and remote small rural). Logistic regression was used to investigate the relationship between late stage at diagnosis and county-level characteristics including level of rurality, persistent poverty, low education and low employment, and patient characteristics.

RESULTS

In the adjusted analysis the rate of stage 4 CRC at diagnosis differed across geographic classification, with patients living in remote small rural counties having the highest rate of stage 4 disease (range: 19.2% in nonadjacent micropolitan counties to 22.7% in remote small rural counties). Other factors, such as patient characteristics, insurance status, and regional practice variation were also significantly associated with late-stage CRC diagnosis.

CONCLUSIONS

Geographic residence is associated with the rate of stage 4 disease at presentation. Additional patient factors are associated with stage 4 CRC disease at diagnosis. Cancer outcomes are worse for rural patients, and late stage at diagnosis may partially account for this disparity. These differences have persisted over time and suggest areas for further research, patient engagement, and education.

Comprehensive analysis of expression profiles of long non‑coding RNAs with associated ceRNA network involved in gastric cancer progression

Long non-coding RNAs (lncRNAs) play critical roles in the development and progression of cancers. The present study aimed to identify novel lncRNAs and associated microRNAs (miRNAs or miRs) and mRNAs in gastric cancer. Differentially expressed lncRNAs (DElncRNAs) and differentially expressed mRNAs (DEmRNAs) of 6 paired gastric cancer and normal tissues were identified using microarray. The DEmiRNAs between gastric cancer and the normal control tissues were identified using miRNA-seq data from Cancer Genome Atlas. Common DElncRNAs from the Cancer RNA-Seq Nexus database and circlncRNAnet database were analyzed. A DElncRNAs-DEmiRNAs-DEmRNAs network was constructed by target prediction. Functional enrichment analysis was employed to predict the function of DEmRNAs in the network. The correlation between the expression of DElncRNAS and DEmRNAs in the network was analyzed. The expression levels of several genes were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). A total of 1,297 DElncRNAs, 2,037 DEmRNAs and 171 DEmiRNAs were identified. Among the 4 lncRNAs common to the 3 datasets, prostate androgen-regulated transcript 1 (PART1) was selected for further analysis. The analysis identified 5 DEmiRNAs and 13 DEmRNAs in the PART1-mediated ceRNA network. The DEmRNAs in the ceRNA network were markedly enriched in cancer-related biological processes (response to hypoxia, positive regulation of angiogenesis and positive regulation of endothelial cell proliferation) and pathways (cGMP-PKG signaling pathway, cAMP signaling pathway and proteoglycans in cancer). Out of the 13 DEmRNAs, 11 were positively associated with PART1. The downregulation of PART1, myosin light chain 9 (MYL9), potassium calcium-activated channel subfamily M alpha 1 (KCNMA1), cholinergic receptor muscarinic 1 (CHRM1), solute carrier family 25 member 4 (SLC25A4) and ATPase Na⁺/K⁺ transporting subunit alpha 2 (ATP1A2) expression levels in gastric cancer was validated by RT-qPCR. On the whole, the current study identified a novel lncRNA and associated miRNAs and mRNAs that are involved in the pathogenesis of gastric cancer that may serve as potential therapeutic targets for the treatment of gastric cancer.

Risk Factors Associated With Circumferential Resection Margin Positivity in Rectal Cancer: A Binational Registry Study

BACKGROUND

Rectal cancer outcomes have improved with the adoption of a multidisciplinary model of care. However, there is a spectrum of quality when viewed from a national perspective, as highlighted by the Consortium for Optimizing the Treatment of Rectal Cancer data on rectal cancer care in the United States.

OBJECTIVE

The aim of this study was to assess and identify predictors of circumferential resection margin involvement for rectal cancer across Australasia.

DESIGN

A retrospective study from a prospectively maintained binational colorectal cancer database was interrogated.

SETTINGS

This study is based on a binational colorectal cancer audit database.

PATIENTS

Clinical information on all consecutive resected rectal cancer cases recorded in the registry from 2007 to 2016 was retrieved, collated, and analyzed.

MAIN OUTCOME MEASURES

The primary outcome measure was positive circumferential resection margin, measured as a resection margin ≤1 mm.

RESULTS

A total of 3367 patients were included, with 261 (7.5%) having a positive circumferential resection margin. After adjusting for hospital and surgeon volume, hierarchical logistic regression analysis identified a 6-variable model encompassing the independent predictors, including urgent operation, abdominoperineal resection, open technique, low rectal cancer, T3 to T4, and N1 to N2. The accuracy of the model was 92.3%, with an receiver operating characteristic of 0.783 (p < 0.0001). The quantitative risk associated with circumferential resection margin positivity ranged from <1% (no risk factors) to 43% (6 risk factors).

LIMITATIONS

This study was limited by the lack of recorded long-term outcomes associated with circumferential resection margin positivity.

CONCLUSIONS

The rate of circumferential resection margin involvement in patients undergoing rectal cancer resection in Australasia is low and is influenced by a number of factors. Risk stratification of outcome is important with the increasing demand for publicly accessible quality data. See Video Abstract at http://links.lww.com/DCR/A512.