Improvements in Colorectal Cancer Incidence Not Experienced by Nonmetropolitan Women: A Population-Based Study From Utah

Rural cancer disparities from Oklahoma cancer and vital records registries 2016-2020

OBJECTIVES

Compared to Oklahoma, 33 states have higher all-cause cancer incidence rates, but only three states have higher all-cause cancer mortality rates. Given this troubling gap between Oklahoma's cancer incidence and mortality rankings, in-depth examination of cancer incidence, staging, and mortality rates among this state's high-risk populations is warranted. This study provides in-depth information on overall and cause-specific cancer incidence and mortality for the rural and urban Oklahoma populations classified by Rural-Urban Continuum Codes (RUCC).

METHODS

Data were publicly available and de-identified, accessed through Oklahoma Statistics on Health Available for Everyone (OK2SHARE). Statistical analysis included calculating age-specific rates, age-adjusted rates, and percentages, as well as assessing temporal patterns using average annual percent change with 95 % confidence intervals determined by Joinpoint regression analysis.

FINDINGS

Urban areas had a higher proportion of female breast cancer cases, while large and small rural areas had higher rates of lung and bronchus cancer. Urban residents were more likely to have private insurance and less likely to have Medicare compared to rural residents. Cancer incidence rates increased with age, and men had higher mortality rates than women. Lung and bronchus cancer was the leading cause of cancer death, with lower rates in urban areas compared to rural areas.

CONCLUSIONS

Findings demonstrate the need to improve the early detection of cancer among the rural populations of Oklahoma. Additionally, the high mortality rates for most types of cancer experienced by the state's rural population underscores the need to improve cancer detection and treatment in these locations.

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.

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.

Rural-urban disparities in colorectal cancer survival and risk among men in Utah: a statewide population-based study

Rural areas of the U.S. experience disproportionate colorectal cancer (CRC) death compared to urban areas. The authors aimed to analyze differences in CRC survival between rural and urban Utah men and investigate potential prognostic factors for survival among these men. A cohort of Utah men diagnosed with CRC between 1997 and 2013 was identified from the Utah Cancer Registry. Survival and prognostic factors were analyzed via 5-year CRC survival and Cox proportional hazards models, stratified by rural/urban residence. Among 4,660 men diagnosed with CRC, 15.3% were living in rural Utah. Compared with urban men, rural CRC patients were diagnosed at older ages and in different anatomic subsites; more were overweight, and current smokers. Differences in stage and treatment were not apparent between rural and urban CRC patients. Compared with urban counterparts, rural men experienced a lower CRC survival (Hazard Ratio 0.55, 95% CI 0.53, 0.58 vs. 0.58, 95% CI 0.56, 0.59). Race and cancer treatment influenced CRC survival among men living in both urban and rural areas. Factors of CRC survival varied greatly among urban and rural men in Utah. The influence of social and environmental conditions on health behaviors and outcomes merits further exploration.

Disparities in cancer survival and incidence by metropolitan versus rural residence in Utah

Cancer disparities in rural and frontier communities are an important issue in Utah because much of Utah is sparsely populated. The aims of this study were to investigate whether there are differences in the cancer incidence and 5‐year survival rates in Utah by metropolitan/rural residence and to investigate disparities in distributions of cancer risk factors. We used cancer registry records to identify patients diagnosed with a first primary cancer in Utah between 2004 and 2008. We estimated 5‐year survival and incidence rates. The Cox proportional hazards model was used to estimate hazard ratios (HRs) for the risk of death. There were 32,498 (86.9%) patients with cancer who lived in metropolitan counties and 4906 (13.1%) patients with cancer who lived in rural counties at the time of cancer diagnosis. Patients with cancer from rural counties were more likely to be older, American Indian/Alaskan Native, non‐Hispanic, male, and diagnosed at higher stage. Rural residents had a five‐year relative survival that was 5.2% lower than metropolitan residents and a 10% increase in risk of death (HR = 1.10, 95% CI = 1.03, 1.18) after adjustment for multiple factors. Overall, the cancer incidence rates in rural counties were lower by 11.9 per 100,000 per year (449.2 in rural counties vs. 461.1 in metropolitan counties). Cancer patients living in rural counties of Utah had different demographic characteristics as well as differences in incidence and survival rates. Further studies with individual‐level data are necessary to investigate the reasons behind these differences in cancer incidence and survival to reduce disparities.