Socioeconomic status and the risk of colorectal cancer: an analysis of more than a half million adults in the National Institutes of Health-AARP Diet and Health Study

A prospective investigation of neighborhood socioeconomic deprivation and self-rated health in a large US cohort

BACKGROUND

Neighborhood characteristics play a critical role in health. Self-rated health (SRH) is an important indicator of quality of life and a strong predictor of premature death. Prospective study on neighborhood deprivation and SRH is limited.

METHODS

We examined neighborhood socioeconomic deprivation with reporting fair/poor SRH at follow-up (2004-2006) in 249,265 men and women (age 50-71) who reported SRH as good or better at baseline (1995-1996) in the NIH-AARP Health and Diet Study. Baseline addresses were geocoded and linked to 2000 Census. Census tract level variables were used to generate a socioeconomic deprivation index by principle component analysis.

RESULTS

Residents of more deprived neighborhoods had a higher risk of developing poor/fair SRH at follow-up, even after adjusting for individual-level factors (Odds ratio (95% confidence interval) _{Q5 vs Q1}: 1.26 (1.20, 1.32), p-trend: <0.0001). The results were largely consistent across subgroups with different demographics, health behaviors, and disease conditions and after excluding participants who moved away from their baseline address.

CONCLUSION

Neighborhood disadvantage predicts SRH over 10 years.

Methodological choices affect cancer incidence rates: a cohort study

Background

Incidence rates are fundamental to epidemiology, but their magnitude and interpretation depend on methodological choices. We aimed to examine the extent to which the definition of the study population affects cancer incidence rates.

Methods

All primary cancer diagnoses in Sweden between 1958 and 2010 were identified from the national Cancer Register. Age-standardized and age-specific incidence rates of 29 cancer subtypes between 2000 and 2010 were calculated using four definitions of the study population: persons resident in Sweden 1) based on general population statistics; 2) with no previous subtype-specific cancer diagnosis; 3) with no previous cancer diagnosis except non-melanoma skin cancer; and 4) with no previous cancer diagnosis of any type. We calculated absolute and relative differences between methods.

Results

Age-standardized incidence rates calculated using general population statistics ranged from 6% lower (prostate cancer, incidence rate difference: -13.5/100,000 person-years) to 8% higher (breast cancer in women, incidence rate difference: 10.5/100,000 person-years) than incidence rates based on individuals with no previous subtype-specific cancer diagnosis. Age-standardized incidence rates in persons with no previous cancer of any type were up to 10% lower (bladder cancer in women) than rates in those with no previous subtype-specific cancer diagnosis; however, absolute differences were <5/100,000 person-years for all cancer subtypes.

Conclusions

For some cancer subtypes incidence rates vary depending on the definition of the study population. For these subtypes, standardized incidence ratios calculated using general population statistics could be misleading. Moreover, etiological arguments should be used to inform methodological choices during study design.

Electronic supplementary material

The online version of this article (doi:10.1186/s12963-017-0120-x) contains supplementary material, which is available to authorized users.

Can Opium Use Contribute to a Higher Risk of Colorectal Cancers? A Matched Case-control Study in Iran

BACKGROUND

Colorectal cancers (CRCs) including colon, rectum and anal cancers are the third most prevalent cancers in the world. There are strong evidence showing the risk of the cigarette smoking, alcohol use, low physical activity and some types of diets in CRCs; however, few studies explored the relationship between opium use and CRCs. This study aimed to investigate the association between opioid use and the incidence of CRCs.

METHODS

In a population-based matched case-control study in Kerman, Iran, 175 patients with colorectal cancers and 350 healthy controls (matched for age, sex, and place of residence) were interviewed from Sep 2014 to Nov 2014. Opium and its derivatives, cigarette, alcohol, and diet use were collected using a valid and reliable questionnaire. Conditional logistic regression was used to estimate odds ratios with 95% confidence intervals.

RESULTS

The use of opioids was associated with an increased risk of CRCs (adjusted odds ratio= 4. 5, 95% CI: 2. 4-8. 7). In addition, a dose-response relationship was observed between the cumulative use of opioids and the incidence of CRCs (with low use OR=3. 7; 95% CI: 1. 5-8. 6 and high use OR= 8. 0; 95% CI: 2. 9-21. 7). This dose-response relationship was also strong in patients with colon cancers, with OR= 3. 9 (95% CI: 1. 5-9. 9) and 9. 4 (95% CI: 3. 3-27. 0) for the low and high uses of opioids, respectively.

CONCLUSION

Opioid use can lead to an increased risk of CRCs. Therefore, it is necessary to implement preventive policies to control the use of opioids.

Early Origins of Adult Cancer Risk Among Men and Women: Influence of Childhood Misfortune?

OBJECTIVE

To examine the effect of five childhood misfortune domains-parental behavior, socioeconomic status, infectious diseases, chronic diseases, and impairments-on all-site and selected site-specific cancer prevalence and all-site cancer incidence.

METHOD

Panel data from the Health and Retirement Study (2004-2012) were used to investigate cancer risk among adults above the age of 50.

RESULTS

Risky parental behavior and impairment in childhood were associated with higher odds of all-site cancer prevalence, and childhood chronic disease was associated with prostate cancer, even after adjusting for adult health and socioeconomic factors. Moreover, having one infectious disease in childhood lowered the odds of colon cancer. Cancer trends varied by race and ethnicity, most notably, higher prostate cancer prevalence among Black men and lower all-site cancer among Hispanic adults.

DISCUSSION

These findings underscore the importance of examining multiple domains of misfortune because the type and amount of misfortune influence cancer risk in different ways.

Colorectal Cancer Screening Navigation for the Underserved: Experience of an Urban Program

Colorectal cancer is the third leading cause of cancer deaths in the United States. Although colorectal cancer screenings are effective and recommended by all clinical practice guidelines, only 65.7% of adults ages 50 to 75 years are screened. Colorectal cancer screening is disproportionately underutilized in inner city populations. In 2011, the University of Pennsylvania Health System created a navigation program to specifically address poor colorectal cancer screening rates and increase access to colorectal cancer screening colonoscopies for patients in the underserved areas of West, South, and Southwest Philadelphia. We directed focus on issues surrounding barriers of screening so that we could best leverage our resources and impact the greatest number of patients. The program was designed to target patients who were either due for, never scheduled, or did not keep previously scheduled colorectal cancer screening colonoscopy appointments, or who were referred by providers concerned that the patients would not keep appointments or would misunderstand preprocedural guidelines. The program strives to improve colorectal health by providing free education and screening navigation through a navigator who assists patients from the first phone call to completion of the colonoscopy. This is accomplished by implementing an effective screening program while providing one-on-one service with a cost-effective navigator reaching out to patients who are nonadherent to colorectal cancer screening. Barriers included not having a companion to escort and transport the patient home from the procedure, poor awareness, fear of the procedure or sedation, limited funds to purchase preparation materials, inability to read or comprehend preparation instructions, and hardship in being contacted or scheduling appointments.

Diet Quality and Colorectal Cancer Risk in the Women's Health Initiative Observational Study

Diet quality index scores on Healthy Eating Index 2010 (HEI-2010), Alternative HEI-2010, alternative Mediterranean Diet Index, and the Dietary Approaches to Stop Hypertension (DASH) index have been inversely associated with all-cause and cancer-specific death. This study assessed the association between these scores and colorectal cancer (CRC) incidence as well as CRC-specific mortality in the Women's Health Initiative Observational Study (1993-2012), a US study of postmenopausal women. During an average of 12.4 years of follow-up, there were 938 cases of CRC and 238 CRC-specific deaths. We estimated multivariate hazard ratios and 95% confidence intervals for relationships between quintiles of diet scores (from baseline food frequency questionnaires) and outcomes. HEI-2010 score (hazard ratios were 0.81, 0.77, and 0.73 with P values of 0.04, 0.01, and <0.01 for quintiles 3-5 vs. quintile 1, respectively) and DASH score (hazard ratios were 0.72, 0.74, and 0.78 with P values of <0.01, <0.01, and 0.03 for quintiles 3-5 vs. quintile 1, respectively), but not other diet scores, were associated with a lower risk of CRC in adjusted models. No diet scores were significantly associated with CRC-specific mortality. Closer adherence to HEI-2010 and DASH dietary recommendations was inversely associated with risk of CRC in this large cohort of postmenopausal women.

Risks of developing breast and colorectal cancer in association with incomes and geographic locations in Texas: a retrospective cohort study

BACKGROUND

No study has been conducted to investigate the spatial pattern and association of socioeconomic status (such as income) with breast and colorectal cancer incidence in Texas, United States. This study aimed to determine whether median household income was associated with the risk of developing breast and colorectal cancer in Texas and to identify higher cancer risks by race/ethnicity and geographic areas.

METHODS

This was a retrospective cohort study with an ecological component in using aggregated measures at the county level. We identified 243,677 women with breast cancer and 155,534 men and women with colorectal cancer residing in 254 counties in Texas in 1995-2011 from the public-use dataset of Texas Cancer Registry. The denominator population and median household income at the county level was obtained from the U.S. Bureau of the Census. Cancer incidence rates were calculated as number of cases per 100,000 persons and age-adjusted using the 2000 US population data. We used the ArcGIS v10.1 (geographic information system software) to identify multiple clustered counties with high and low cancer incidences in Texas.

RESULTS

Age-adjusted breast cancer incidence rate in the highest median income quintile group was 151.51 cases per 100,000 in 2008-2011 as compared to 98.95 cases per 100,000 in the lowest median income quintile group. The risk of colorectal cancer appeared to decrease with increasing median income in racial/ethnic population. Spatial analysis revealed the significant low breast cancer incidence cluster regions located in southwest US-Mexico border counties in Texas.

CONCLUSIONS

This study demonstrated that higher income was associated with an increased risk of breast cancer and a decreased risk of colorectal cancer in Texas. There were geographic variations with cancer incidence clustered in high risk areas in Texas. Future studies may need to explore more factors that might explain income and cancer risk associations and their geographic variations.

Worldwide burden of colorectal cancer: a review

Colorectal cancer is a major public health problem, being the third most commonly diagnosed cancer and the fourth cause of cancer death worldwide. There is wide variation over time among the different geographic areas due to variable exposure to risk factors, introduction and uptake of screening as well as access to appropriate treatment services. Indeed, a large proportion of the disparities may be attributed to socioeconomic status. Although colorectal cancer continues to be a disease of the developed world, incidence rates have been rising in developing countries. Moreover, the global burden is expected to further increase due to the growth and aging of the population and because of the adoption of westernized behaviors and lifestyle. Colorectal cancer screening has been proven to greatly reduce mortality rates that have declined in many longstanding as well as newly economically developed countries. Statistics on colorectal cancer occurrence are essential to develop targeted strategies that could alleviate the burden of the disease. The aim of this paper is to provide a review of incidence, mortality and survival rates for colorectal cancer as well as their geographic variations and temporal trends.

Temporal Dietary Patterns Derived among the Adult Participants of the National Health and Nutrition Examination Survey 1999-2004 Are Associated with Diet Quality

BACKGROUND

Temporal dietary patterns, the distribution of energy or nutrient intakes observed over a period of time, is an emerging area of dietary patterns research that incorporates time of dietary intake with frequency and amount of intake to determine population clusters that may have similar characteristics or outcomes related to diet quality.

OBJECTIVE

We examined whether differences in diet quality were present between clusters of individuals with similar daily temporal dietary patterns.

DESIGN

The first-day 24-hour dietary recall data from the cross-sectional National Health and Nutrition Examination Survey, 1999-2004, were used to determine proportional energy intake, time of intake, frequency of intake occasions, and mean diet quality.

PARTICIPANTS/SETTING

Data from 9,326 US adults aged 20 to 65 years were included.

STATISTICAL ANALYSES PERFORMED

The mean diet quality, classified by the Healthy Eating Index-2005, of participant clusters with similar temporal dietary patterns derived on the basis of individual proportional energy intake, time of intake, and frequency of intake, were inferentially compared using multiple linear regression that controlled for potential confounders and other covariates (P<0.05/6).

RESULTS

Diet quality differences were present between US population clusters exhibiting similar daily temporal dietary patterns (P<0.001 with one exception, which was P=0.08). Participant characteristics of race/ethnicity, age, household poverty-income ratio, and body mass index were associated with the temporal dietary patterns. The cluster representing the temporal dietary pattern with proportionally equivalent energy consumed during three evenly spaced eating occasions had a significantly greater mean total Healthy Eating Index-2005 score compared with the other temporal dietary pattern clusters.

CONCLUSIONS

Temporal dietary patterns are associated with differences in US adult daily diet quality, demonstrating that elements beyond food and nutrient intake, such as time, can be incorporated with dietary patterns to determine links to diet quality that enhance knowledge of the complicated interplay of time and dietary patterns.

Race and Prevalence of Large Bowel Polyps Among the Low-Income and Uninsured in South Carolina

BACKGROUND

Compared to whites, blacks have higher colorectal cancer incidence and mortality rates and are at greater risk for early-onset disease. The reasons for this racial disparity are poorly understood, but one contributing factor could be differences in access to high-quality screening and medical care.

AIMS

The present study was carried out to assess whether a racial difference in prevalence of large bowel polyps persists within a poor and uninsured population (n = 233, 124 blacks, 91 whites, 18 other) undergoing screening colonoscopy.

METHODS

Eligible patients were uninsured, asymptomatic, had no personal history of colorectal neoplasia, and were between the ages 45-64 years (blacks) or 50-64 years (whites, other). We examined the prevalence of any adenoma (conventional, serrated) and then difference in adenoma/polyp type by race and age categories.

RESULTS

Prevalence for ≥1 adenoma was 37 % (95 % CI 31-43 %) for all races combined and 36 % in blacks <50 years, 38 % in blacks ≥50 years, and 35 % in whites. When stratified by race, blacks had a higher prevalence of large conventional proximal neoplasia (8 %) compared to whites (2 %) (p value = 0.06) but a lower prevalence of any serrated-like (blacks 18 %, whites 32 %; p value = 0.02) and sessile serrated adenomas/polyps (blacks 2 %, whites 8 % Chi-square p value; p = 0.05).

CONCLUSIONS

Within this uninsured population, the overall prevalence of adenomas was high and nearly equal by race, but the racial differences observed between serrated and conventional polyp types emphasize the importance of taking polyp type into account in future research on this topic.

The impact of preventive screening resource distribution on geographic and population-based disparities in colorectal cancer in Mississippi

Background

The state of Mississippi has the highest colorectal cancer (CRC) mortality rate in the USA. The geographic distribution of CRC screening resources and geographic- and population-based CRC characteristics in Mississippi are investigated to reveal the geographic disparity in CRC screening.

Methods

The primary practice sites of licensed gastroenterologists and the addresses of licensed medical facilities offering on-site colonoscopies were verified via telephone surveys, then these CRC screening resource data were geocoded and analyzed using Geographic Information Systems. Correlation analyses were performed to detect the strength of associations between CRC screening resources, CRC screening behavior and CRC outcome data.

Results

Age-adjusted colorectal cancer incidence rates, mortality rates, mortality-to-incidence ratios, and self-reported endoscopic screening rates from the years 2006 through 2010 were significantly different for Black and White Mississippians; Blacks fared worse than Whites in all categories throughout all nine Public Health Districts. CRC screening rates were negatively correlated with CRC incidence rates and CRC mortality rates. The availability of gastroenterologists varied tremendously throughout the state; regions with the poorest CRC outcomes tended to be underserved by gastroenterologists.

Conclusions

Significant population-based and geographic disparities in CRC screening behaviors and CRC outcomes exist in Mississippi. The effects of CRC screening resources are related to CRC screening behaviors and outcomes at a regional level, whereas at the county level, socioeconomic factors are more strongly associated with CRC outcomes. Thus, effective control of CRC in rural states with high poverty levels requires both adequate preventive CRC screening capacity and a strategy to address fundamental causes of health care disparities.

Race and Insurance Differences in the Receipt of Adjuvant Chemotherapy Among Patients With Stage III Colon Cancer

PURPOSE

Although the incidence and mortality of colon cancer in the United States has declined over the past two decades, blacks have worse outcomes than whites. Variations in treatment may contribute to mortality differentials.

METHODS

Patients diagnosed with stage III colon cancer were randomly sampled from the SEER program from the years 1990, 1991, 1995, 2000, 2005, and 2010. Patients were categorized as non-Hispanic white (n = 835) or black (n = 384). Treatment data were obtained from a review of the medical records, and these data were verified through contact with the original treating physicians. Log-binomial regression models were used to estimate the association between race and receipt of adjuvant chemotherapy. Effect modification by insurance was assessed with use of single referent models.

RESULTS

Receipt of adjuvant chemotherapy among both white and black patients increased from the period encompassing the years 1990 and 1991 (white, 58%; black, 45%) to the year 2005 (white, 72%; black, 71%) and then decreased in the year 2010 (white, 66%; black, 57%). There were marked racial disparities in the time period of 1990 to 1991 and again in 2010, with black patients less likely to receive adjuvant chemotherapy as compared with white patients (risk ratio [RR], .82; 95% CI, .72 to .93). For black patients, receipt of adjuvant chemotherapy did not differ across insurance categories (RR for private insurance, .80; 95% CI, .69 to .93; RR for Medicare, .84; 95% CI, .69 to 1.02; and RR for Medicaid, .84; 95% CI, .69 to 1.02), although a larger proportion had Medicaid in all years of the study as compared with white patients.

CONCLUSION

The chemotherapy differential narrowed after the time period of 1990 to 1991, but our findings suggest that the disparity reemerged in 2010. Recent decreases in chemotherapy use may be due, in part, to the economic downturn and an increase in Medicaid coverage.

MicroRNAs potential utility in colon cancer: Early detection, prognosis, and chemosensitivity

Over the past decade, research has shown that aberrant expression of microRNA (miRNA) is involved in colorectal cancer development and progression. MicroRNAs are small sequences of non-coding RNA that regulate expression of genes involved in important cellular functions, such as cell differentiation, multiplication, and apoptosis. A specific miRNA may display the effects of a tumor suppressor or oncogene. Altered miRNA expression is found in colorectal cancer (CRC) and patterns of miRNA expression correlate with CRC detection and outcome. Studies also have examined the use of circulating serum miRNA and fecal miRNA expression as non-invasive markers for early detection. Here, we review recent evidence demonstrating the potential role of miRNA in CRC and the implications of its use in the diagnosis, prognosis, and management of CRC.

How can we boost colorectal and hepatocellular cancer screening among underserved populations?

Colorectal cancer (CRC) and hepatocellular carcinoma (HCC) are common causes of cancer incidence and mortality in the USA, particularly among underserved populations such as racial/ethnic minorities, the under-/uninsured, and individuals with low socioeconomic status. Although screening can reduce cancer-related mortality, participation is suboptimal among underserved populations, likely serving as the largest contributor to observed inequities in HCC and CRC outcomes among US populations. In this narrative review, we highlight inequities across populations in the USA with respect to incidence and mortality for CRC and HCC and highlight potential causes, with a focus on screening rates. In addition, drawing from the recent literature, we highlight promising strategies for increasing screening for HCC and CRC and propose future research and policy solutions to optimize screening rates. With focused implementation of screening strategies and novel research, the burden of HCC and CRC can be reduced among underserved populations.

Socioeconomic status influences the likelihood but not the outcome of liver resection for colorectal liver metastasis

BACKGROUND

The aim of this study was to compare the socioeconomic profile of patients undergoing liver resection for colorectal liver metastasis (CLM) in a regional hepatopancreatobiliary unit with that of the local population. A further aim was to determine if degree of deprivation is associated with tumour recurrence after resection.

METHODS

A retrospective analysis of patients undergoing liver resection for CLM was performed. Geodemographic segmentation was used to divide the population into five categories of socioeconomic status (SES).

RESULTS

During a 7-year period, 303 patients underwent resection for CLM. The proportion of these patients in the two least deprived categories of SES was greater than that of the local population (50.2% versus 40.2%) and the proportion in the two most deprived categories was lower (18.3% versus 30.1%) (P < 0.001). There was no difference in recurrence rate (P = 0.867) or disease-free survival among categories of SES (P = 0.913). Multivariate analysis demonstrated no association between SES and tumour recurrence (P = 0.700).

CONCLUSIONS

Liver resection for CLM is performed more commonly among the least socioeconomically deprived population than among the most deprived. However, degree of deprivation was not associated with tumour recurrence after resection.

Mortality determinants in colorectal cancer patients at different grades: a prospective, cohort study in Iran

BACKGROUND

Colorectal cancer (CRC) is an important cause of mortality and morbidity in many communities worldwide. This population based study was conducted to assess determinants of colorectal mortality in Iranian patients.

MATERIALS AND METHODS

A cohort of 1,127 cases of confirmed colorectal cancer registered in a population based registry covering 10 referral hospital in Tehran, Iran, were followed for five years. Information about tumor characteristics, smoking status and family history were collected at base line and survival status were followed every six months by contacting patient or next of kin (if patients died during the follow-up). The cause of death for each case was validated by verbal autopsy and referring to patient medical records at the time of death. The data were analyzed by Stata software using univariate and multivariate analysis (Cox regression). In building the model a p value of less than 5% was considered as significant.

RESULTS

The age at diagnosis was 53.5±14 years. Sixty one percent were male. Colorectal mortality among the patients was 96.9 person-years among men and 83 person-years among women. Seventy five percent of patients lived for 2.72 years, 50% for 5.83, and 25% for 13 years after the diagnosis of colorectal cancer. The age at diagnosis was significantly different between men and women (p<0.03). Higher tumor grade predicted higher death rate; the adjusted hazard ratios were 1.79 (95%CI, 0.88-3.61), 2.16 (95%CI, 1.07-4.37), and 3.1 (95%CI, 1.51-6.34) for grades II, III, and IV respectively when they were compared with grade I as reference. Ethnicity, marital status, family history of cancer, and smoking were related to survival with different degrees of magnitude.

CONCLUSIONS

Among many factors related to survival among the colorectal patients, tumor grade and smoking showed the highest magnitudes of association.

Linking of primary care records to census data to study the association between socioeconomic status and cancer incidence in Southern Europe: a nation-wide ecological study

BACKGROUND

Area-based measures of economic deprivation are seldom applied to large medical records databases to establish population-scale associations between deprivation and disease.

OBJECTIVE

To study the association between deprivation and incidence of common cancer types in a Southern European region.

METHODS

Retrospective ecological study using the SIDIAP (Information System for the Development of Research in Primary Care) database of longitudinal electronic medical records for a representative population of Catalonia (Spain) and the MEDEA index based on urban socioeconomic indicators in the Spanish census. Study outcomes were incident cervical, breast, colorectal, prostate, and lung cancer in 2009-2012. The completeness of SIDIAP cancer recording was evaluated through linkage of a geographic data subset to a hospital cancer registry. Associations between MEDEA quintiles and cancer incidence was evaluated using zero-inflated Poisson regression adjusted for sex, age, smoking, alcoholism, obesity, hypertension, and diabetes.

RESULTS

SIDIAP sensitivity was 63% to 92% for the five cancers studied. There was direct association between deprivation and lung, colorectal, and cervical cancer: incidence rate ratios (IRR) 1.82 [1.64-2.01], IRR 1.60 [1.34-1.90], IRR 1.22 [1.07-1.38], respectively, comparing the most deprived to most affluent areas. In wealthy areas, prostate and breast cancers were more common: IRR 0.92 [0.80-1.00], IRR 0.91 [0.78-1.06]. Adjustment for confounders attenuated the association with lung cancer risk (fully adjusted IRR 1.16 [1.08-1.25]), reversed the direction of the association with colorectal cancer (IRR 0.90 [0.84-0.95]), and did not modify the associations with cervical (IRR 1.27 [1.11-1.45]), prostate (0.74 [0.69-0.80]), and breast (0.76 [0.71-0.81]) cancer.

CONCLUSIONS

Deprivation is associated differently with the occurrence of various cancer types. These results provide evidence that MEDEA is a useful, area-based deprivation index for analyses of the SIDIAP database. This information will be useful to improve screening programs, cancer prevention and management strategies, to reach patients more effectively, particularly in deprived urban areas.

Somatic gene mutations in African Americans may predict worse outcomes in colorectal cancer

BACKGROUND AND OBJECTIVE

African Americans have worse outcomes in colorectal cancer (CRC) than Caucasians. We sought to determine if KRAS, BRAF and PIK3CA mutations might contribute to the racial differences in CRC outcome.

METHODS

DNA was extracted from tissue microarrays made from CRC samples from 67 African Americans and 237 Caucasians. Mutations in KRAS, BRAF, and PIK3CA were evaluated by PCR sequencing. We also examined microsatellite instability (MSI) status. Associations of mutation status with tumor stage and grade were examined using a logistic regression model. Cox proportional hazards models were used to estimate the all-cause mortality associated with mutational status, race and other clinicopathologic features.

RESULTS

KRAS mutations were more common in African Americans than among Caucasians (37% vs 21%, p=0.01) and were associated with advanced stage (unadjusted odds ratio (OR)=3.31, 95% confidence interval (CI) 1.03-10.61) and grade (unadjusted OR=5.60, 95% CI 1.01-31.95) among African Americans. Presence of BRAF mutations was also positively associated with advanced tumor stage (adjusted OR=3.99, 95%CI 1.43-11.12) and grade (adjusted OR=3.93, 95%CI 1.05-14.69). PIK3CA mutations showed a trend toward an association with an increased risk of death compared to absence of those mutations (adjusted for age, sex and CRC site HR=1.89, 95% CI 0.98-3.65). Among African Americans, the association was more evident (adjusted for age, sex and CRC site HR=3.92, 95% CI 1.03-14.93) and remained significant after adjustment for MSI-H status and combined education-income level, with HR of 12.22 (95%CI 1.32-121.38).

CONCLUSIONS

Our results suggest that African Americans may have different frequencies of somatic genetic alterations that may partially explain the worse prognosis among African Americans with CRC compared to whites.

Neighborhood deprivation and risk of cancer incidence, mortality and survival: results from a population-based cohort study in Japan

BACKGROUND

In many developed countries, socioeconomic status is associated with cancer incidence and survival. However, research in Japan is sparse. We examined the association between neighborhood deprivation based on the Japanese Deprivation Index and the risk of incidence, mortality and survival from total and major cancers in the Japan Public Health Center-based Prospective Study.

METHODS

86,112 participants were followed through the end of 2009. A total of 10,416 incident cases and 5,510 deaths from cancer were identified among 1,348,437 person-years of follow-up (mean follow-up: 15.7 years). The Japanese deprivation index was used to access neighborhood deprivation. Hazard ratios and 95% confidence intervals were calculated by Cox regression analysis.

RESULTS

We found no associations between neighborhood deprivation index and the incidence of total and major cancers. In some cancer risks or deaths, however, we found positive or inverse associations with a higher deprivation index, such as a decreased risk of colorectal cancer incidence and an increased risk of liver cancer incidence and deaths in women.

CONCLUSION

Although some positive or inverse associations were detected for specific sites, the neighborhood deprivation index has no substantial overall association with the risk of incidence, mortality and survival from cancer in the Japanese population.

Specific metabolic biomarkers as risk and prognostic factors in colorectal cancer

Advances in genomics, molecular pathology and metabolism have generated many candidate biomarkers of colorectal cancer with potential clinical value. Epidemiological and biological studies suggest a role for adiposity, dyslipidaemia, hyperinsulinemia, altered glucose homeostasis, and elevated expression of insulin-like growth factor (IGF) axis members in the risk and prognosis of cancer. This review discusses some recent past and current approaches being taken by researches in obesity and metabolic disorders. The authors describe three main systems as the most studied metabolic candidates of carcinogenesis: dyslipidemias, adipokines and insulin/IGF axis. However, each of these components is unsuccessful in defining the diseases risk and progression, while their co-occurrence increases cancer incidence and mortality in both men and women.

Does ethnicity affect survival following colorectal cancer? A prospective, cohort study using Iranian cancer registry

BACKGROUND

The present study compared the differences between survivals of patients with colorectal cancer according to their ethnicity adjusted for other predictors of survival.

METHODS

In this prospective cohort study patients were followed up from definite diagnosis of colorectal cancer to death. Totally, 2431 person-year follow-ups were undertaken for 1127 colorectal cancer patients once every six months. The data were analyzed by stata software using bivariate analysis, multivariate analysis, and Cox regression.

RESULTS

The age at diagnosis was significantly different between men and women (p<0.03). 61.2% were male and the rest were female. Most patients were Fars (51.2%), followed by Turciks (21.5%), Kurds (8.2%), and 7.5% Lurs. Of the patients, 75% had a survival of more than 2.72 years, 50% a survival of 5.83 years, and 25% longer than 13.1 years after diagnosis. Risk ratio was significantly different among ethnics (p<0.05). The variables of ethnicity, being non married, tumor grade, family history of cancer, and smoking were considered as determinants of the patients' survival in Cox regression model. The median survival time in Fars, Kurds, Lurs, Turks and other ethnics was 5.83, 2.44, 5.49, and 8.52 years, respectively.

CONCLUSION

Ethnicity and access to healthcare are predictors of survival of patients with colorectal cancer which may define priorities in controlling cancer and implementing interventional and prevention plans.

Preoperative factors predicting clinical outcome following laparoscopic fundoplication

BACKGROUND

Antireflux surgery is effective for the treatment of gastroesophageal reflux, but not all patients benefit equally from it. The challenge is to identify the patients who will ultimately benefit from antireflux surgery. The aim of this study was to identify preoperative factors that predict clinical outcome after antireflux surgery, with special interest in the influence of socioeconomic factors.

METHODS

Preoperative clinical and socioeconomic data from 1,650 patients who were to undergo laparoscopic fundoplication were collected prospectively. Clinical outcome measures (persistent heartburn, dysphagia, satisfaction) were assessed at short-term (1 year) and longer-term (≥ 3 years) follow-up.

RESULTS

At early follow-up, male gender (relative risk [RR] 1.091, p < 0.001) and the presence of a hiatus hernia (RR 1.065, p = 0.002) were independently associated with less heartburn. Male gender was also associated with higher overall satisfaction (RR 1.046, p = 0.034). An association was found between postoperative dysphagia and age (RR 0.988, p = 0.007) and the absence of a hiatus hernia (RR 0.767, p = 0.001). At longer-term follow-up, only male gender (RR 1.125, p < 0.001) was an independent prognostic factor for heartburn control. Male gender (RR 0.761, p = 0.001), the presence of a hiatus hernia (RR 0.823, p = 0.014), and cerebrovascular comorbidities (RR 1.306, p = 0.019) were independent prognosticators for dysphagia at longer-term follow-up. A hiatus hernia was the only factor associated with better overall satisfaction. Socioeconomic factors did not influence any clinical outcomes at short- and longer-term follow-up.

CONCLUSION

Male gender and hiatus hernia are associated with a better clinical outcome following laparoscopic fundoplication, whereas socioeconomic status does not influence outcome.

Long-term follow-up reveals low incidence of colorectal cancer, but frequent need for resection, among Australian patients with inflammatory bowel disease

BACKGROUND & AIMS

Inflammatory bowel disease can require surgical resection and also lead to colorectal cancer (CRC). We investigated the cumulative incidence of resection surgeries and CRC among patients with ulcerative colitis (UC) or Crohn's disease (CD).

METHODS

We analyzed data from a cohort of patients who participated in an inflammatory bowel disease study (504 with UC and 377 with CD) at 2 academic medical centers in Sydney, Australia from 1977 to 1992 (before the development of biologic therapies). We collected follow-up data on surgeries and development of CRC from hospital and community medical records or via direct contact with patients during a median time period of 14 years. Cumulative incidences of resection surgeries and CRC were calculated by competing risk survival analysis.

RESULTS

Among patients with UC, CRC developed in 24, for a cumulative incidence of 1% at 10 years (95% confidence interval [CI], 0%-2%), 3% at 20 years (95% CI, 1%-5%), and 7% at 30 years (95% CI, 4%-10%). Their cumulative incidence of colectomy was 15% at 10 years (95% CI, 11%-19%), 26% at 20 years (95% CI, 21%-30%), and 31% at 30 years (95% CI, 25%-36%). Among patients with CD, 5 of 327 with colon disease developed CRC, with a cumulative incidence of CRC of 1% at 10 years (95% CI, 0%-2%), 1% at 20 years (95% CI, 0%-2%), and 2% at 30 years (95% CI, 0%-4%). Among all patients with CD, the cumulative incidence of resection was 32% at 5 years (95% CI, 27%-37%), 43% at 10 years (95% CI, 37%-49%), and 53% at 15 years (95% CI, 46%-58%). Of these 168 subjects, 42% required a second resection within 15 years of the first surgery (95% CI, 33%-50%).

CONCLUSIONS

Patients with UC have a low incidence of CRC during a 30-year period (7% or less); the incidence among patients with CD is even lower. However, almost one-third of patients with UC and about 50% of those with CD will require surgery.

Challenges and possible solutions to colorectal cancer screening for the underserved

Colorectal cancer (CRC) is a leading cause of cancer mortality worldwide. CRC incidence and mortality can be reduced through screening. However, in the United States, screening participation remains suboptimal, particularly among underserved populations such as the uninsured, recent immigrants, and racial/ethnic minority groups. Increasing screening rates among underserved populations will reduce the US burden of CRC. In this commentary focusing on underserved populations, we highlight the public health impact of CRC screening, list key challenges to screening the underserved, and review promising approaches to boost screening rates. We identify four key policy and research priorities to increase screening among underserved populations: 1) actively promote the message, "the best test is the one that gets done"; 2) develop and implement methods to identify unscreened individuals within underserved population groups for screening interventions; 3) develop and implement approaches for organized screening delivery; and 4) fund and enhance programs and policies that provide access to screening, diagnostic follow-up, and CRC treatment for underserved populations. This commentary represents the consensus of a diverse group of experts in cancer control and prevention, epidemiology, gastroenterology, and primary care from across the country who formed the Coalition to Boost Screening among the Underserved in the United States. The group was organized and held its first annual working group meeting in conjunction with the World Endoscopy Organization's annual Colorectal Cancer Screening Committee meeting during Digestive Disease Week 2012 in San Diego, California.

The risk of developing a second primary cancer in melanoma patients: a comprehensive review of the literature and meta-analysis

The number of cutaneous melanoma survivors has been increasing for years due to improvements in early diagnosis and subsequent prolonged survival. These patients are at increased risk of developing a second melanoma and a second primary malignancy (SPM) at other sites as well. We performed a review of scientific literature and meta-analysis to evaluate the risk of developing a SPM (other than melanoma) among melanoma patients. Twenty-three independent papers and over 350,000 melanoma patients were included. Risk of cancer among melanoma survivors was increased overall (1.57, 95% CI 1.29-1.90) and at several sites: bone (2.09, 95% CI 1.08-4.05), non-melanoma skin cancer (4.01, 95% CI 1.81-8.87), soft tissue (6.80, 95% CI 1.29-35.98), colon-rectum (1.12, 95% CI 1.00-1.25), female breast (1.14, 95% CI 1.07-1.22), kidney (1.34, 95% CI 1.23-1.45), prostate (1.25, 95% CI 1.13-1.37) and non-Hodgkin lymphoma (1.37, 95% CI 1.22-1.54). The overall risk of SPM showed a tendency to decrease as the time from melanoma diagnosis lengthened. Most of our findings may be explained by the tendency of some exposures, which are risk factors for different tumors, to occur simultaneously in the same individuals. These results suggest primary and secondary cancer prevention counselling for melanoma survivors.

Colorectal cancer statistics, 2014

Colorectal cancer is the third most common cancer and the third leading cause of cancer death in men and women in the United States. This article provides an overview of colorectal cancer statistics, including the most current data on incidence, survival, and mortality rates and trends. Incidence data were provided by the National Cancer Institute's Surveillance, Epidemiology, and End Results program and the North American Association of Central Cancer Registries. Mortality data were provided by the National Center for Health Statistics. In 2014, an estimated 71,830 men and 65,000 women will be diagnosed with colorectal cancer and 26,270 men and 24,040 women will die of the disease. Greater than one-third of all deaths (29% in men and 43% in women) will occur in individuals aged 80 years and older. There is substantial variation in tumor location by age. For example, 26% of colorectal cancers in women aged younger than 50 years occur in the proximal colon, compared with 56% of cases in women aged 80 years and older. Incidence and death rates are highest in blacks and lowest in Asians/Pacific Islanders; among males during 2006 through 2010, death rates in blacks (29.4 per 100,000 population) were more than double those in Asians/Pacific Islanders (13.1) and 50% higher than those in non-Hispanic whites (19.2). Overall, incidence rates decreased by approximately 3% per year during the past decade (2001-2010). Notably, the largest drops occurred in adults aged 65 and older. For instance, rates for tumors located in the distal colon decreased by more than 5% per year. In contrast, rates increased during this time period among adults younger than 50 years. Colorectal cancer death rates declined by approximately 2% per year during the 1990s and by approximately 3% per year during the past decade. Progress in reducing colorectal cancer death rates can be accelerated by improving access to and use of screening and standard treatment in all populations.

Genetic ancestry is associated with colorectal adenomas and adenocarcinomas in Latino populations

Colorectal cancer rates in Latin American countries are less than half of those observed in the United States. Latin Americans are the resultant of generations of an admixture of Native American, European, and African individuals. The potential role of genetic admixture in colorectal carcinogenesis has not been examined. We evaluate the association of genetic ancestry with colorectal neoplasms in 190 adenocarcinomas, 113 sporadic adenomas and 243 age- and sex-matched controls enrolled in a multicentric case-control study in Colombia. Individual ancestral genetic fractions were estimated using the STRUCTURE software, based on allele frequencies and assuming three distinct population origins. We used the Illumina Cancer Panel to genotype 1,421 sparse single-nucleotide polymorphisms (SNPs), and Northern and Western European ancestry, LWJ and Han Chinese in Beijing, China populations from the HapMap project as references. A total of 678 autosomal SNPs overlapped with the HapMap data set SNPs and were used for ancestry estimations. African mean ancestry fraction was higher in adenomas (0.13, 95% confidence interval (95% CI)=0.11-0.15) and cancer cases (0.14, 95% CI=0.12-0.16) compared with controls (0.11, 95% CI=0.10-0.12). Conditional logistic regression analysis, controlling for known risk factors, showed a positive association of African ancestry per 10% increase with both colorectal adenoma (odds ratio (OR)=1.12, 95% CI=0.97-1.30) and adenocarcinoma (OR=1.19, 95% CI=1.05-1.35). In conclusion, increased African ancestry (or variants linked to it) contributes to the increased susceptibility of colorectal cancer in admixed Latin American population.

How microRNAs influence both hereditary and inflammatory-mediated colon cancers

MicroRNAs have emerged as important post-translational regulators of gene expression and are involved in several physiological and pathological states including the pathogenesis of human colon cancers. In regards to tumor development, microRNAs can act as oncogenes or tumor suppressors. Two hereditary predispositions (i.e., Lynch syndrome and familial adenomatous polyposis) contribute to the development of colon cancer. In addition, individuals who suffer from inflammatory bowel diseases such as Crohn's disease or ulcerative colitis have a higher risk of developing colon cancer. Here, we discuss the occurrence of the deregulated expression of microRNAs in colon cancer that arise as a result of hereditary predisposition and inflammatory bowel disease.

An international review of the main cost-effectiveness drivers of virtual colonography versus conventional colonoscopy for colorectal cancer screening: is the tide changing due to adherence?

OBJECTIVES

The majority of recent cost-effectiveness reviews concluded that computerised tomographic colonography (CTC) is not a cost-effective colorectal cancer (CRC) screening strategy yet. The objective of this review is to examine cost-effectiveness of CTC versus optical colonoscopy (COL) for CRC screening and identify the main drivers influencing cost-effectiveness due to the emergence of new research.

METHODS

A systematic review was conducted for cost-effectiveness studies comparing CTC and COL as a screening tool and providing outcomes in life-years saved, published between January 2006 and November 2012.

RESULTS

Nine studies were included in the review. There was considerable heterogeneity in modelling complexity and methodology. Different model assumptions and inputs had large effects on resulting cost-effectiveness of CTC and COL. CTC was found to be dominant or cost-effective in three studies, assuming the most favourable scenario. COL was found to be not cost effective in one study.

CONCLUSIONS

CTC has the potential to be a cost-effective CRC screening strategy when compared to COL. The most important assumptions that influenced the cost-effectiveness of CTC and COL were related to CTC threshold-based reporting of polyps, CTC cost, CTC sensitivity for large polyps, natural history of adenoma transition to cancer, AAA parameters and importantly, adherence. There is a strong need for a differential consideration of patient adherence and compliance to CTC and COL. Recent research shows that laxative-free CTC screening has the potential to become a good alternative screening method for CRC as it can improve patient uptake of screening.

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.

Colorectal cancer risk factors among the population of South-East Siberia: a case-control study

Colorectal cancer remains one of the most widespread malignancies in the world. However, there is a lack of comprehensive studies considering colorectal cancer risk factors among Russian populations, particularly in Siberia. The aim of this investigation was to determine the impact of various lifestyle, dietary, family, and socioeconomical factors on colorectal cancer risk in South-East Siberia. We recruited 185 Russian colorectal cancer cases and 210 gender-, age-, and ethnicity-matched asymptomatic controls with no history of any malignant tumor, using a specially designed questionnaire to obtain relevant information. After the statistical analysis, we defined several significant factors affecting colorectal cancer risk. Among these were smoking (OR=2.13, 95%CI=1.4- 3.24, P=0.0004), being overweight (BMI between 25-30, OR=2.45, 95%CI=1.49-4.03, P=0.0004), alcohol drinking (OR=8.73, 95%CI=5.49-13.87, P<0.0001), beer drinking (OR=9.24, 95%CI=5.14-16.61, P<0.0001), consumption of hard liquor (OR=9.37, 95%CI=5.92-14.82, P<0.0001), excessive red meat consumption (P<0.0001), excessive intake of red meat products (P<0.0001), excessive intake of dairy products (P<0.0001), excessive sour cream and cheese consumption (P<0.0001 and 0.0002, respectively), spicy food consumption (OR=2.87, 95%CI=1.9-4.33, P<0.0001), family history of gastrointestinal malignant tumors (OR=3.99, 95%CI=2.09-7.59, P<0.0001), and income exceeding twice the subsistence minimum (OR=5.34, 95%CI=3.35-8.53, P<0.0001). Certain factors, such as high concentration of salt in the food and precancerous colonic lesions, demonstrated borderline significance (OR=3.45, 95%CI=1.68-7.1, P=0.0008, and OR=5.25, 95%CI=1.94-14.22, P=0.001, respectively). Some factors were established as protective, like consumption of rye bread and both rye and wheat bread (OR=0.32, 95%CI=0.21-0.5, P<0,0001, and OR=0.07, 95%CI=0.02-0.21, P<0.0001, respectively), and also low concentration of salt in the food, although this was of borderline significance (OR=0.43, 95%CI=0.26-0.69, P=0.0006). ABO and Rhesus blood antigens were not associated with increased colorectal cancer risk. These results should be definitely applied for elaboration of programs of colorectal cancer prevention in Russia, particularly in Siberia.

Correlation of cancer incidence with diet, smoking and socio- economic position across 22 districts of Tehran in 2008

BACKGROUND

Variation in cancer incidence in geographical locations is due to different lifestyles and risk factors. Diet and socio-economic position (SEP) have been identified as important for the etiology of cancer but patterns are changing and inconsistent. The aim of this study was to investigate correlations of the incidence of common cancers with food groups, total energy, smoking, and SEP.

MATERIALS AND METHODS

In an ecological study, disaggregated cancer data through the National Cancer Registry in Iran (2008) and dietary intake, smoking habits and SEP obtained through a population based survey within the Urban Health Equity Assessment (Urban-HEART) project were correlated across 22 districts of Tehran.

RESULTS

Consumption of fruit, meat and dairy products adjusted for energy were positively correlated with bladder, colorectal, prostate and breast and total cancers in men and women, while these cancers were adversely correlated with bread and fat intake. Also prostate, breast, colorectal, bladder and ovarian cancers had a positive correlation with SEP; there was no correlation between SEP and skin cancer in both genders and stomach cancer in men.

CONCLUSIONS

The incidence of cancer was higher in some regions of Tehran which appeared to be mainly determined by SEP rather than dietary intake. Further individual data are required to investigate reasons of cancer clustering.

Contribution of behavioral risk factors and obesity to socioeconomic differences in colorectal cancer incidence

BACKGROUND

Health behaviors are known risk factors for colorectal cancer and are more common in low socioeconomic status (SES) populations. We evaluated the extent to which behavioral risk factors and body mass index (BMI) explain SES disparities in colorectal cancer incidence, overall and by tumor location.

METHODS

We analyzed prospective National Institutes of Health-AARP Diet and Health Study data on 506 488 participants who were recruited in 1995-1996 from six US states and two metropolitan areas and followed through 2006. Detailed baseline data on risk factors for colorectal cancer, including health behaviors, were obtained using questionnaires. SES was measured by self-reported education and census-tract data. The outcome was primary incident invasive colorectal adenocarcinoma. Poisson regression was used to estimate the association between SES and risk of incident colorectal cancer, with adjustment for age, sex, race and ethnicity, family history, and state of residence. The model estimates were used to derive percentage mediation by behavioral risk factors; bias-corrected 95% confidence intervals were obtained through bootstrap techniques.

RESULTS

Seven-thousand six-hundred seventy-six participants developed colorectal cancer during follow-up. SES differences in prevalence of physical inactivity, unhealthy diet, smoking, and unhealthy weight each explained between 11.3% (BMI) and 21.6% (diet) of the association between education and risk of colorectal cancer and between 8.6% (smoking) and 15.3% (diet) of the association between neighborhood SES and risk of colorectal cancer. Health behaviors and BMI combined explained approximately 43.9% (95% CI = 35.1% to 57.9%) of the association of education and 36.2% (95% CI = 28.0% to 51.2%) of the association of neighborhood SES with risk of colorectal cancer. The percentage explained by all factors and BMI combined was largest for right colon cancers and smallest for rectal cancers.

CONCLUSION

A substantial proportion of the socioeconomic disparity in risk of new-onset colorectal cancer, and particularly of right colon cancers, may be attributable to the higher prevalence of adverse health behaviors in low-SES populations.

Neighborhood socioeconomic status and use of colonoscopy in an insured population--a retrospective cohort study

BACKGROUND

Low-socioeconomic status (SES) is associated with a higher colorectal cancer (CRC) incidence and mortality. Screening with colonoscopy, the most commonly used test in the US, has been shown to reduce the risk of death from CRC. This study examined if, among insured persons receiving care in integrated healthcare delivery systems, differences exist in colonoscopy use according to neighborhood SES.

METHODS

We assembled a retrospective cohort of 100,566 men and women, 50-74 years old, who had been enrolled in one of three US health plans for ≥1 year on January 1, 2000. Subjects were followed until the date of first colonoscopy, date of disenrollment from the health plan, or December 31, 2007, whichever occurred first. We obtained data on colonoscopy use from administrative records. We defined screening colonoscopy as an examination that was not preceded by gastrointestinal conditions in the prior 6-month period. Neighborhood SES was measured using the percentage of households in each subject's census-tract with an income below 1999 federal poverty levels based on 2000 US census data. Analyses, adjusted for demographics and comorbidity index, were performed using Weibull regression models.

RESULTS

The average age of the cohort was 60 years and 52.7% were female. During 449,738 person-years of follow-up, fewer subjects in the lowest SES quartile (Q1) compared to the highest quartile (Q4) had any colonoscopy (26.7% vs. 37.1%) or a screening colonoscopy (7.6% vs. 13.3%). In regression analyses, compared to Q4, subjects in Q1 were 16% (adjusted HR = 0.84, 95% CI: 0.80-0.88) less likely to undergo any colonoscopy and 30%(adjusted HR = 0.70, CI: 0.65-0.75) less likely to undergo a screening colonoscopy.

CONCLUSION

People in lower-SES neighborhoods are less likely to undergo a colonoscopy, even among insured subjects receiving care in integrated healthcare systems. Removing health insurance barriers alone is unlikely to eliminate disparities in colonoscopy use.