Incidence and survival of colorectal cancer among Hispanics in the United States: a population-based study

A Review Article: The Relationship Between Obesity and Colorectal Cancer

PURPOSE OF REVIEW

This article aims to review the recent literature assessing the relationship between obesity and colorectal carcinogenesis, the effect of obesity on the treatment of colorectal cancer (CRC), tools available to help augment the increased risk, and outcomes for patients who are affected by both obesity and colorectal cancer.

RECENT FINDINGS

The biochemical mechanisms contributing to CRC carcinogenesis are not well understood but are suspected to be related to adipose tissue leading to a pro-inflammatory state and changes in the gut microbiome. Individuals with obesity are at higher risk for CRC development, worse oncologic outcomes, and increased rates of post-operative complications. Bariatric surgery decreases CRC risk but results with GLP-1 agonists are heterogeneous. Prehabilitation is the only weight loss method that has been demonstrated to decrease risks of post-operative morbidity in this population. Obesity augments CRC risk and outcomes. There are persistent knowledge gaps in etiology and epidemiology for the increased CRC risk in obese patients and more research is required to identify the therapeutic advantage of weight loss on CRC risk.

Orbital Apex Metastases From Primary Colorectal Adenocarcinoma: A Rare Cause for Unilateral Vision Loss

Colorectal cancer is one of the most common causes of cancer-related death in the United States. Although it frequently metastasizes to adjacent structures such as the liver, orbital metastases are exceedingly uncommon. Additionally, the morbidity and mortality associated with colorectal cancer appear to be shifting to a younger population, a phenomenon that is exacerbated in minority populations. We present a case of orbital metastasis from colorectal carcinoma in a young Hispanic male. This uncommon presentation of disease emphasizes the link between healthcare disparity and differential outcomes of colorectal cancer.

Molecular and Sociodemographic Colorectal Cancer Disparities in Latinos Living in Puerto Rico

BACKGROUND

The incidence of sporadic colorectal cancer (CRC) among individuals <50 years (early-onset CRC) has been increasing in the United States (U.S.) and Puerto Rico. CRC is currently the leading cause of cancer death among Hispanic men and women living in Puerto Rico (PRH). The objective of this study was to characterize the molecular markers and clinicopathologic features of colorectal tumors from PRH to better understand the molecular pathways leading to CRC in this Hispanic subpopulation.

METHODS

Microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and KRAS and BRAF mutation status were analyzed. Sociodemographic and clinicopathological characteristics were evaluated using Chi-squared and Fisher's exact tests.

RESULTS

Of the 718 tumors analyzed, 34.2% (n = 245) were early-onset CRC, and 51.7% were males. Among the tumors with molecular data available (n = 192), 3.2% had MSI, 9.7% had BRAF, and 31.9% had KRAS mutations. The most common KRAS mutations observed were G12D (26.6%) and G13D (20.0%); G12C was present in 4.4% of tumors. A higher percentage of Amerindian admixture was significantly associated with early-onset CRC.

CONCLUSIONS

The differences observed in the prevalence of the molecular markers among PRH tumors compared to other racial/ethnic groups suggest a distinct molecular carcinogenic pathway among Hispanics. Additional studies are warranted.

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.

Implementation of Universal Tumor Screening of Colorectal Cancer for Detection of Lynch Syndrome at a Hispanic-Rich County Hospital

INTRODUCTION

In 2014, a reflexive screening protocol for Lynch syndrome (LS) via an immunohistochemistry (IHC) assay was shown to be cost-effective; however, the screening rates at a predominant Hispanic-rich institution are unclear. We hypothesized that implementation of a universal tumor screening (UTS) protocol requiring screening for LS via IHC in patients with newly diagnosed colorectal cancer (CRC) at our Hispanic-rich institution would improve detection of LS by increasing screening rates.

METHODS AND MATERIALS

This is a retrospective analysis of screening rates of 3 sequential cohorts of newly diagnosed patients with CRC between January 2012 and April 2016 at the University Health System and with follow-up at National Cancer Institute-designated Mays Cancer Center at University of Texas Health San Antonio. Cohort 1 consisted of patients screened using old screening guidelines (PRE). Cohort 2 consisted of patients screened when treating clinicians were receiving education on the new protocol (PERI). Cohort 3 consisted of patients screened after implementation of the UTS protocol (POST).

RESULTS

The majority of 312 patients were Hispanic (62.5%), 18.1% were < 50 years, and 81.9% were ≥ 50 years of age (median age, 57 years). Of patients with CRC screened for LS via IHC, the PRE, PERI, and POST cohorts had screening rates of 31%, 64%, and 58%, respectively. We found significant differences when comparing the PRE with POST sequential cohorts (P < .01).

CONCLUSION

The quality of Lynch syndrome-related family histories and screening rates were significantly improved after implementation in our Hispanic-rich population. Future studies are warranted to provide insight into clinical effects of increased screening, provider and patient surveillance, and screening-related systemic barriers.

Rightward shift in colorectal cancer: experience in 1101 patients

BACKGROUND

In the past decades the right colon cancer showed a higher incidence rate than left colon cancer. This trend is known as "proximal shift" or "rightwards shift." We evaluated rightward shift phenomenon in our region.

METHODS

We collected data from 1101 colorectal cancer patients who underwent curative surgery at Parma University Hospital from 01 January 2004 through 01 January 2018. We divided patients into seven subgroups according to the time of surgery to evaluate epidemiological changes through the years of colon cancer.

RESULTS

We found a non-linear rightward shift trend of CRC. The incidence of RCC was the 40% between 2004-2005 and 51% in the biennium 2016-2017 (60% in 2012-2013 and 57% in 2014-2015). The patients with RCC were significantly older than patients with LCC. RCCs have poor differentiated tumors. Metastatic disease showed a similar distribution both in left and right CRCs. Peritoneum was the most common metastasis location from right-sided colon cancer.

CONCLUSIONS

Data suggest the existence of two different tumor entities in CRC between right-sided colon cancer and left-sided colon cancer. The proximal shift may be a reflection of improved screening programs, diagnostic accuracy and population aging. Ethnicity, gender, diet, environment, and socioeconomic status contribute to CRC incidence and prevalence in different regions.

Risk factors for colorectal cancer significantly vary by anatomic site

Objective

To conduct an anatomic site-specific case–control study of candidate colorectal cancer (CRC) risk factors.

Design

Case–control study of US veterans with >1 colonoscopy during 1999–2011. Cases had cancer registry-identified CRC at colonoscopy, while controls were CRC free at colonoscopy and within 3 years of colonoscopy. Primary outcome was CRC, stratified by anatomic site: proximal, distal, or rectal. Candidate risk factors included age, sex, race/ethnicity, body mass index, height, diabetes, smoking status, and aspirin exposure summarised by adjusted ORs and 95% CIs.

Results

21 744 CRC cases (n=7017 rectal; n=7039 distal; n=7688 proximal) and 612 646 controls were included. Males had significantly higher odds relative to females for rectal cancer (OR=2.84, 95% CI 2.25 to 3.58) than distal cancer (OR=1.84, 95% CI 1.50 to 2.24). Relative to whites, blacks had significantly lower rectal cancer odds (OR=0.88, 95% CI 0.82 to 0.95), but increased distal (OR=1.27, 95% CI 1.19 to 1.37) and proximal odds (OR=1.62, 95% CI 1.52 to 1.72). Diabetes prevalence was more strongly associated with proximal (OR=1.29, 95% CI 1.22 to 1.36) than distal (OR=1.15, 95% CI 1.08 to 1.22) or rectal cancer (OR=1.12, 95% CI 1.06 to 1.19). Current smoking was more strongly associated with rectal cancer (OR=1.81, 95% CI 1.68 to 1.95) than proximal cancer (OR=1.53, 95% CI 1.43 to 1.65) or distal cancer (OR=1.46, 95% CI 1.35 to 1.57) compared with never smoking. Aspirin use was significantly more strongly associated with reduced rectal cancer odds (OR=0.71, 95% CI 0.67 to 0.76) than distal (OR=0.85, 95% CI 0.81 to 0.90) or proximal (OR=0.91, 95% CI 0.86 to 0.95).

Conclusion

Candidate CRC risk factor associations vary significantly by anatomic site. Accounting for site may enable better insights into CRC pathogenesis and cancer control strategies.

Disparities in colon and rectal cancer queried individually between Hispanics and Whites

Background

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer related deaths in the United States. Racial disparities between Hispanics and Whites exist for incidence of late-onset (LO) CRC. However, not much is known about potential disparities between colon cancer (CC) and rectal cancer (RC) incidence queried individually.

Methods

Using the SEER database data from 2000 to 2010, we obtained the national estimates of CC and RC for Hispanics and Whites. We analyzed trends in incidence, mortality, gender and stage of disease for early-onset (EO) (<50 years old) and LO (>50 years old) CC and RC.

Results

In Hispanics, the overall incidence of CC and RC increased by 47% and 52%, respectively; while in Whites, the overall incidence of CC and RC decreased by 13% and 2% respectively. Incidence of EO CC increased in both Hispanics and Whites by 83% and 17%, respectively, and incidence of EO RC also increased for both groups with a 76% increase in Hispanics and a 34% increase in Whites. For LO CC, the incidence increased by 37% in Hispanics while it decreased by 17% in Whites and for LO RC, the trend in incidence increased in Hispanics by 41%, but decreased in Whites by 11%.

Conclusions

This study established that the incidence of CC and RC are different and there is racial disparity in incidence between Whites and Hispanics. This study, hopefully, will help in crafting public policy that might help in addressing this disparity.

Barriers and Facilitators to Colorectal Cancer Screening Within a Hispanic Population

INTRODUCTION

Colorectal cancer (CRC) is the third leading cancer cause of death among US Hispanics. CRC screening among the Hispanic population is lower compared with non-Hispanic Whites.

METHOD

The purpose of this qualitative, exploratory study was to better understand the barriers and facilitators of CRC screening and preference for stool-based testing collection methods among the predominantly Hispanic population of El Paso, Texas. Nine focus groups were conducted by a trained bilingual facilitator with a moderator guide informed by the literature. Transcripts of the focus groups were entered into qualitative analysis software and a thematic network was developed.

RESULTS

Fifty-six participants were recruited: average age was 68.5 years, 58.9% were female, 98.2% were Hispanic, 87.5% had an annual income of less than $20,000, 58.9% had 9th grade education or less, 12.5% had a discount program, and 5.4% had no insurance. Barriers to CRC screening included cost, fear, and embarrassment. Facilitators to screening included in-person health education and physician recommendation. Participants preferred the hygienic nature of a stool test collected with a brush and bottle.

CONCLUSION

Overall, there was a lack of knowledge regarding CRC and significant barriers to CRC screening. A community-based CRC screening program was subsequently developed from our findings.

Racial-Ethnic Disparities in Late-Stage Colorectal Cancer Among Hispanics and Non-Hispanic Whites of New Mexico

INTRODUCTION

Hispanics in New Mexico are diagnosed with more later-stage colorectal cancer (CRC) than non-Hispanic Whites (NHW). Our study evaluated the interaction of race/ethnicity and risk factors for later-stage III and IV CRC among patients in New Mexico.

METHOD

CRC patients ages 30 to 75 years ( n = 163, 46% Hispanic) completed a survey on key explanatory clinical, lifestyle, preventive health, and demographic variables for CRC risk. Adjusted logistic regression models examined whether these variables differentially contributed to later-stage CRC among NHW versus Hispanics.

RESULTS

Compared with NHW, Hispanics had a higher prevalence of later-stage CRC ( p = .007), diabetes ( p = .006), high alcohol consumption ( p = .002), low education ( p = .003), and CRC diagnosis due to symptoms ( p = .06). Compared with NHW, Hispanics reporting high alcohol consumption (odds ratio [OR] = 7.59; 95% confidence interval [CI] = 1.31-43.92), lower education (OR = 3.5; 95% CI = 1.28-9.65), being nondiabetic (OR = 3.23; 95% CI = 1.46-7.15), or ever smokers (OR = 2.4; 95% CI = 1.03-5.89) were at higher risk for late-stage CRC. Adjusting for CRC screening did not change the direction or intensity of the odds ratios.

CONCLUSION

The ethnicity-risk factor interactions, identified for late-stage CRC, highlight significant factors for targeted intervention strategies aimed at reducing the burden of later-stage CRC among Hispanics in New Mexico with broad applicability to other Hispanic populations.

Benefits of marriage on relative and conditional relative cancer survival differ between males and females in the USA

PURPOSE

The purpose of the paper is to assess the influence of marital status on conditional relative survival of cancer according to sex.

METHODS

Analyses involved 779,978 males and 1,032,868 females diagnosed with 1 of 13 cancer types between 2000 and 2008, and followed through 2013. Data are from the Surveillance, Epidemiology, and End Results (SEER) Program. Regression models were adjusted for age, sex, race, and tumor stage.

RESULTS

Five-year relative survival conditional on years already survived is higher among married patients with less lethal cancers (oral cavity and pharynx, colon and rectum, breast, urinary bladder, kidney and renal pelvis, melanoma of the skin, thyroid, lymphoma). For more lethal cancers, married patients have similar (liver, lung and bronchus, pancreas, leukemia) or poorer (brain and other nervous system) cancer survival. Separated/divorced or widowed patients have the lowest conditional relative survival rates. For most cancers, 5-year cancer relative survival rates conditional on time already survived through 5 years approach 70 to 90% of that for the general population. The beneficial effect of marriage on survival decreases with years already survived. Superior conditional relative survival rates in females decrease with time already survived and are less pronounced in married patients.

CONCLUSION

Five-year relative survival rates improve with time already survived. The benefits of marriage on conditional relative survival are greater for less lethal cancers. Greater 5-year conditional relative survival rates in females narrow with time already survived and are less pronounced in married patients.

IMPLICATIONS FOR CANCER SURVIVORS

Conditional relative survival rates of cancer can lead to more informed decisions and understanding regarding treatment and prognosis.

DNA mismatch repair deficiency and hereditary syndromes in Latino patients with colorectal cancer

BACKGROUND

The landscape of hereditary syndromes and clinicopathologic characteristics among US Latino/Hispanic individuals with colorectal cancer (CRC) remains poorly understood.

METHODS

A total of 265 patients with CRC who were enrolled in the Hispanic Colorectal Cancer Study were included in the current study. Information regarding CRC risk factors was elicited through interviews, and treatment and survival data were abstracted from clinical charts. Tumor studies and germline genetic testing results were collected from medical records or performed using standard molecular methods.

RESULTS

The mean age of the patients at the time of diagnosis was 53.7 years (standard deviation, 10.3 years), and 48.3% were female. Overall, 21.2% of patients reported a first‐degree or second‐degree relative with CRC; 3.4% met Amsterdam I/II criteria. With respect to Bethesda guidelines, 38.5% of patients met at least 1 criterion. Of the 161 individuals who had immunohistochemistry and/or microsatellite instability testing performed, 21 (13.0%) had mismatch repair (MMR)‐deficient (dMMR) tumors. dMMR tumors were associated with female sex (61.9%), earlier age at the time of diagnosis (50.4 ± 12.4 years), proximal location (61.9%), and first‐degree (23.8%) or second‐degree (9.5%) family history of CRC. Among individuals with dMMR tumors, 13 (61.9%) had a germline MMR mutation (MutL homolog 1 [MLH1] in 6 patients; MutS homolog 2 [MSH2] in 4 patients; MutS homolog 6 [MHS6] in 2 patients; and PMS1 homolog 2, mismatch repair system component [PMS2] in 1 patient). The authors identified 2 additional MLH1 mutation carriers by genetic testing who had not received immunohistochemistry/microsatellite instability testing. In total, 5.7% of the entire cohort were confirmed to have Lynch syndrome. In addition, 6 individuals (2.3%) had a polyposis phenotype.

CONCLUSIONS

The percentage of dMMR tumors noted among Latino individuals (13%) is similar to estimates in non‐Hispanic white individuals. In the current study, the majority of individuals with dMMR tumors were confirmed to have Lynch syndrome. Cancer 2017. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. Cancer 2017;123:3732–3743. © 2017 American Cancer Society

The landscape of hereditary syndromes and clinicopathologic characteristics among Latino/Hispanic individuals in the United States with colorectal cancer remains poorly understood. Using data from the Hispanic Colorectal Cancer Study, approximately 13% of cases in the current study appear to have mismatch repair‐deficient tumors, 61.9% of which will be confirmed to have Lynch syndrome.

Disparities in incidence of early- and late-onset colorectal cancer between Hispanics and Whites: A 10-year SEER database study

BACKGROUND

Racial disparities in incidence of colorectal cancer (CRC) exist. In Hispanics, CRC was the second most commonly diagnosed cancer in 2012.

METHODS

We abstracted the national estimates for Hispanics/Whites with CRC using the SEER database between 2000 and 2010. Trends in incidence, mortality, gender and stage of disease were analyzed for early-onset (age<50; EO - young) and late-onset (age>50; LO - old) cases.

RESULTS

The overall incidence of CRC increased by 48% in Hispanics. 38% increase in incidence of LO CRC and 80% increase in incidence of EO CRC was seen in this ethnic group. Hispanics and Whites showed higher percentage of distant tumors for both age groups. There was no deviation in overall trend between males and females.

CONCLUSIONS

Although there is an overall decrease in incidence of CRC in Whites increase was seen in Hispanics. While incidence of EO CRC is increasing in both races, LO CRC incidence is increasing in Hispanics not in Whites. This data suggest that disparities in incidence of EO and LO CRC exist between Hispanics and Whites.

Rising Incidence of Colorectal Cancer Among Young Hispanics in Texas

GOALS

To investigate trends in colorectal cancer (CRC) incidence and survival among Hispanics in Texas.

BACKGROUND

The incidence of CRC is rising among young adults in the United States. Given Texas' large Hispanic population, investigating CRC trends in Texas may provide valuable insight into the future of CRC epidemiology in an ever-diversifying US population.

STUDY

Data from the Texas Cancer Registry (1995 to 2010) were used to calculate age-adjusted CRC rates based on the 2000 US standard population. Annual percentage change (APC) and 5-year cancer-specific survival (CSS) rates were reported by age, race/ethnicity, stage, and anatomic location.

RESULTS

Of 123,083 CRC cases, 11% occurred in individuals below 50 years old, 26% of whom were Hispanic. Incidence was highest among African Americans (AAs; 76.3/100,000), followed by non-Hispanic whites (NHWs; 60.2/100,000) and Hispanics (50.8/100,000). Although overall CRC incidence declined between 1995 and 2010 (APC, -1.8%; P<0.01), trends differed by age and race/ethnicity. Among individuals 50 years and above, the rate of decline was statistically significant among NHWs (APC, -2.4%; P<0.01) and AAs (APC, -1.3%; P<0.01) but not among Hispanics (APC, -0.6%; P=0.13). In persons aged 20 to 39 years, CRC incidence rose significantly among Hispanics (APC, 2.6%; P<0.01) and NHWs (APC, 2.4%; P<0.01), but not AAs (APC, 0.3%; P=0.75). CSS rates among Hispanics and NHWs were comparable across most age groups and cancer stages, whereas CSS rates among AAs were generally inferior to those observed among NHWs and Hispanics.

CONCLUSIONS

Although CRC incidence has declined in Texas, it is rising among young Hispanics and NHWs while declining more slowly among older Hispanics than among older NHWs and AAs.

Variability in Cancer Risk and Outcomes Within US Latinos by National Origin and Genetic Ancestry

Latinos have lower rates for most common cancer sites and higher rates of some less common cancers (gallbladder, liver, gastric, and cervical) than other ethnic/racial groups. Latinos are a highly heterogeneous population with diverse national origins, unique genetic admixture patterns, and wide spectrum of socio-demographic characteristics. Across the major cancers (breast, colorectal, prostate, lung, and liver) US-born Latinos have higher incidence and worse survival than foreign-born, and those with low-socioeconomic status have the lowest incidence. Puerto Rican and Cuban Latinos have higher incidence rates than Mexican Latinos. We have identified the following themes as understudied and critical to reduce the cancer burden among US Latinos: (1) etiological studies considering key sources of heterogeneity, (2) culturally sensitive cancer prevention strategies, (3) description of the molecular tumor landscape to guide treatments and improve outcomes, and (4) development of prediction models of disease risk and outcomes accounting for heterogeneity of Latinos.

Genome-wide association study of colorectal cancer in Hispanics

This manuscript describes the first large-scale genome-wide association study of colorectal cancer in Hispanics and Latinos. Our results demonstrate the broad replication of known susceptibility regions and the importance of fine-mapping in ethnic minority populations.

Genome-wide association studies (GWAS) have identified 58 susceptibility alleles across 37 regions associated with the risk of colorectal cancer (CRC) with P < 5×10⁻⁸. Most studies have been conducted in non-Hispanic whites and East Asians; however, the generalizability of these findings and the potential for ethnic-specific risk variation in Hispanic and Latino (HL) individuals have been largely understudied. We describe the first GWAS of common genetic variation contributing to CRC risk in HL (1611 CRC cases and 4330 controls). We also examine known susceptibility alleles and implement imputation-based fine-mapping to identify potential ethnicity-specific association signals in known risk regions. We discovered 17 variants across 4 independent regions that merit further investigation due to suggestive CRC associations (P < 1×10⁻⁶) at 1p34.3 (rs7528276; Odds Ratio (OR) = 1.86 [95% confidence interval (CI): 1.47–2.36); P = 2.5×10⁻⁷], 2q23.3 (rs1367374; OR = 1.37 (95% CI: 1.21–1.55); P = 4.0×10⁻⁷), 14q24.2 (rs143046984; OR = 1.65 (95% CI: 1.36–2.01); P = 4.1×10⁻⁷) and 16q12.2 [rs142319636; OR = 1.69 (95% CI: 1.37–2.08); P=7.8×10⁻⁷]. Among the 57 previously published CRC susceptibility alleles with minor allele frequency ≥1%, 76.5% of SNPs had a consistent direction of effect and 19 (33.3%) were nominally statistically significant (P < 0.05). Further, rs185423955 and rs60892987 were identified as novel secondary susceptibility variants at 3q26.2 (P = 5.3×10^–5) and 11q12.2 (P = 6.8×10⁻⁵), respectively. Our findings demonstrate the importance of fine mapping in HL. These results are informative for variant prioritization in functional studies and future risk prediction modeling in minority populations.

Health disparities in colorectal cancer among racial and ethnic minorities in the United States

In the 2010 Census, just over one-third of the United States (US) population identified themselves as being something other than being non-Hispanic white alone. This group has increased in size from 86.9 million in 2000 to 111.9 million in 2010, representing an increase of 29 percent over the ten year period. Per the American Cancer Society, racial and ethnic minorities are more likely to develop cancer and die from it when compared to the general population of the United States. This is particularly true for colorectal cancer (CRC). The primary aim of this review is to highlight the disparities in CRC among racial and ethnic minorities in the United States. Despite overall rates of CRC decreasing nationally and within certain racial and ethnic minorities in the US, there continue to be disparities in incidence and mortality when compared to non-Hispanic whites. The disparities in CRC incidence and mortality are related to certain areas of deficiency such as knowledge of family history, access to care obstacles, impact of migration on CRC and paucity of clinical data. These areas of deficiency limit understanding of CRC's impact in these groups and when developing interventions to close the disparity gap. Even with the implementation of the Patient Protection and Affordable Healthcare Act, disparities in CRC screening will continue to exist until specific interventions are implemented in the context of each of racial and ethnic group. Racial and ethnic minorities cannot be viewed as one monolithic group, rather as different segments since there are variations in incidence and mortality based on natural history of CRC development impacted by gender, ethnicity group, nationality, access, as well as migration and socioeconomic status. Progress has been made overall, but there is much work to be done.

Cancer statistics for Hispanics/Latinos, 2015

Cancer is the leading cause of death among Hispanics/Latinos, who represent the largest racial/ethnic minority group in the United States, accounting for 17.4% (55.4 million/318 million) of the total US population in 2014. Every 3 years, the American Cancer Society reports on cancer statistics for Hispanics based on incidence data from the National Cancer Institute, the Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries and mortality data from the National Center for Health Statistics. Among Hispanics in 2015, there will be an estimated 125,900 new cancer cases diagnosed and 37,800 cancer deaths. For all cancers combined, Hispanics have 20% lower incidence rates and 30% lower death rates compared with non-Hispanic whites (NHWs); however, death rates are slightly higher among Hispanics during adolescence (aged 15-19 years). Hispanic cancer rates vary by country of origin and are generally lowest in Mexicans, with the exception of infection-associated cancers. Liver cancer incidence rates in Hispanic men, which are twice those in NHW men, doubled from 1992 to 2012; however, rates in men aged younger than 50 years declined by 43% since 2003, perhaps a bellwether of future trends for this highly fatal cancer. Variations in cancer risk between Hispanics and NHWs, as well as between subpopulations, are driven by differences in exposure to cancer-causing infectious agents, rates of screening, and lifestyle patterns. Strategies for reducing cancer risk in Hispanic populations include increasing the uptake of preventive services (e.g., screening and vaccination) and targeted interventions to reduce obesity, tobacco use, and alcohol consumption.

Comparing the effect of a decision aid plus patient navigation with usual care on colorectal cancer screening completion in vulnerable populations: study protocol for a randomized controlled trial

BACKGROUND

Screening can reduce colorectal cancer (CRC) incidence and mortality. However, screening is underutilized in vulnerable patient populations, particularly among Latinos. Patient-directed decision aids can increase CRC screening knowledge, self-efficacy, and intent; however, their effect on actual screening test completion tends to be modest. This is probably because decision aids do not address some of the patient-specific barriers that prevent successful completion of CRC screening in these populations. These individual barriers might be addressed though patient navigation interventions. This study will test a combined decision aid and patient navigator intervention on screening completion in diverse populations of vulnerable primary care patients.

METHODS/DESIGN

We will conduct a multisite, randomized controlled trial with patient-level randomization. Planned enrollment is 300 patients aged 50 to 75 years at average CRC risk presenting for appointments at two primary clinics in North Carolina and New Mexico. Intervention participants will view a video decision aid immediately before the clinic visit. The 14 to 16 minute video presents information about fecal occult blood tests and colonoscopy and will be viewed on a portable computer tablet in English or Spanish. Clinic-based patient navigators are bilingual and bicultural and will provide both face-to-face and telephone-based navigation. Control participants will view an unrelated food safety video and receive usual care. The primary outcome is completion of a CRC screening test at six months. Planned subgroup analyses include examining intervention effectiveness in Latinos, who will be oversampled. Secondarily, the trial will evaluate the intervention effects on knowledge of CRC screening, self-efficacy, intent, and patient-provider communication. The study will also examine whether patient ethnicity, acculturation, language preference, or health insurance status moderate the intervention effect on CRC screening.

DISCUSSION

This pragmatic randomized controlled trial will test a combined decision aid and patient navigator intervention targeting CRC screening completion. Findings from this trial may inform future interventions and implementation policies designed to promote CRC screening in vulnerable patient populations and to reduce screening disparities.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02054598.

Associations between circulating 1,25(OH)₂D concentration and odds of metachronous colorectal adenoma

Cellular-level studies demonstrate that the availability of the secosteroid hormone 1α,25-dihydroxyvitamin D [1,25(OH)2D] to colon cells promotes anti-carcinogenic activities. Although epidemiological data are relatively sparse, suggestive inverse trends have been reported between circulating 1,25(OH)2D concentration and colorectal neoplasia. We therefore sought to evaluate the relationship between circulating 1,25(OH)2D concentrations and odds for metachronous colorectal adenomas among 1,151 participants from a randomized trial of ursodeoxycholic acid for colorectal adenoma prevention. No relationship between 1,25(OH)2D and overall odds for metachronous lesions was observed, with ORs (95% CIs) of 0.80 (0.60-1.07) and 0.81 (0.60-1.10) for participants in the second and third tertiles, respectively, compared with those in the lowest (p-trend = 0.17). However, a statistically significant inverse association was observed between circulating 1,25(OH)2D concentration and odds of proximal metachronous adenoma, with an OR (95% CI) of 0.71 (0.52-0.98) for individuals in the highest tertile of 1,25(OH)2D compared with those in the lowest (p-trend = 0.04). While there was no relationship overall between 1,25(OH)2D and metachronous distal lesions, there was a significantly reduced odds for women, but not men, in the highest 1,25(OH)2D tertile compared with the lowest (OR 0.53; 95% CI 0.27-1.03; p-trend = 0.05; p-interaction = 0.08). The observed differences in associations with proximal and distal adenomas could indicate that delivery and activity of vitamin D metabolites in different anatomic sites in the colorectum varies, particularly by gender. These results identify novel associations between 1,25(OH)2D and metachronous proximal and distal colorectal adenoma, and suggest that future studies are needed to ascertain potential mechanistic differences in 1,25(OH)2D action in the colorectum.

Prevalence of colorectal neoplasia among young African Americans and Hispanic Americans

BACKGROUND

The disproportionately higher incidence of and mortality from colorectal cancer (CRC) among African Americans (AA) led the American College of Gastroenterology to recommend screening starting at age 45 in 2005.

AIM

The purpose of this study was to determine the prevalence of colorectal neoplasia among 40-49-year-old inner city AA and Hispanic Americans (HA).

METHODS

We reviewed the medical records of 2,435 inner city AA and HA who underwent colonoscopy regardless of indication and compared the prevalence of colorectal neoplasia between AA and HA patients. We used logistic regression models to calculate odds ratios (OR) and 95 % confidence intervals (CI).

RESULTS

There were 2,163 AAs and 272 HA. There were 57 % women in both groups. A total of 158 (7 %) AA and 9 (3 %) HA (P = 0.014) underwent the procedures for CRC screening. When compared to HAs, AAs had higher prevalence of any polyp (35 vs. 18 %, OR = 2.53; 95 % CI 1.82-3.52). Overall, AA had higher prevalence of colorectal neoplasia (adenoma and cancer) when compared to HAs (16 vs. 10 %; OR = 1.68; 95 % CI 1.10-2.56).

CONCLUSION

We observed a higher frequency of colorectal neoplasia among 40-49-year-old AAs as compared to HAs suggesting an increased susceptibility to CRC risk in this population.

Interaction between age and race alters predicted survival in colorectal cancer

BACKGROUND

Racial disparities in colorectal cancer persist. Late stage at presentation and lack of stage-specific treatment may be contributing factors. We sought to evaluate the magnitude of disparity remaining after accounting for gender, stage, and treatment using predicted survival models.

METHODS

We used institutional tumor registries from a public health system (two hospitals) and a not-for-profit health system (nine hospitals) from 1995 to 2011. Demographics, stage at diagnosis, treatment, and survival were recorded. Hazard ratios (HRs) and predicted HRs were determined by Cox regression and postestimation analyses.

RESULTS

There were 6,990 patients: 55.7 % white, 23.6 % African American, 15.1 % Hispanic, and 5.6 % Asian/other. Predictors of survival were surgery (HR 0.57, 95 % confidence interval [CI] 0.46-0.70), chemotherapy (HR 0.7, 95 % CI 0.62-0.79), female gender (HR 0.87, 95 % CI 0.83-0.90), age (HR 1.04, 95 % CI 1.03-1.05), and African American race (HR 3.6, 95 % CI 1.5-8.4). Balancing for stage, gender, and treatment reduced the predicted HRs for African Americans by 28 % and Hispanics by 17 %. In this model, African American and Hispanics still had the worst predicted HRs at younger ages, but whites had the worst predicted HR after age 75.

CONCLUSIONS

Gender, stage, and treatment partially accounted for worsened survival in African Americans and Hispanics at all ages. At younger ages, race-related disparities remained which may reflect tumor biology or other unknown factors. Once gender, stage, and treatment are balanced at older ages, the increased mortality observed in whites may be due to factors such as comorbidities. Further system- and patient-level study is needed to investigate reasons for colorectal cancer survival disparities.