Secular changes in colorectal cancer incidence by subsite, stage at diagnosis, and race/ethnicity, 1992-2001

Locally advanced rectal cancer in a young adult affected with dyskeratosis congenita (Zinsser-Cole-Engman syndrome): a case report

BACKGROUND

Dyskeratosis congenita (DKC), also known as Zinsser-Cole-Engman syndrome, is a progressive genetic disease with a triad of reticulate skin pigmentation, nail dystrophy, and leukoplakia. Approximately 8-10% of patients with DKC develop malignancies, and cases of colorectal cancer with DKC in young people have been reported previously.

CASE PRESENTATION

A 25-year-old man with DKC since approximately 10 years of age developed fever and lower abdominal discomfort. Diagnostic imaging revealed locally advanced rectal cancer with lymph node metastasis, direct invasion of the prostate, and pelvic abscess due to tumor microperforation (cT4bN2M0 cStage IIIC). Biopsy showed well to moderately differentiated ductal adenocarcinoma. Genetic testing was negative for RAS and BRAF gene mutations, and microsatellite instability (MSI) testing was also negative. After sigmoid colostomy, the patient was treated with total neoadjuvant therapy (TNT) with systemic chemotherapy (six courses of FOLFOX + panitumumab) followed by chemoradiation therapy (50.4 Gy with capecitabine). After TNT, the primary tumor and metastatic lymph nodes shrank. According to the findings of colonoscopy and magnetic resonance image (MRI), we diagnosed near complete response (near-CR) and decided to follow the patient without surgery by every 3 months re-evaluation. However, 5 months after TNT, tumor regrowth was detected on colonoscopy and imaging, and the patient underwent total pelvic exenteration. He developed paralytic ileus as a postoperative complication, and was discharged on the 38th postoperative day. Pathological examination revealed a residual tumor with invasion of the periprostatic tissue. There was no metastasis in the pararectal and lateral pelvic lymph nodes, but one extramural non-contiguous cancerous extension (tumor deposit) was observed (ypT4bN1cM0 ypStage IIIC). The patient has been free of recurrence for one year after surgery.

CONCLUSIONS

DKC often develops into various tumors in the digestive system at an early age; therefore, appropriate surveillance may be required. In addition, considering that cancers in patients with DKC occur at a young age, fertility preservation and survivorship are also important, and adequate explanations and care should be provided to patients before and after treatment.

Poorly differentiated mucinous carcinoma of the ascending colon complicated by bilateral ovarian mature cystic teratomas in a 17-year-old female patient: a case report

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers worldwide, and screening colonoscopy has led to a decreasing incidence rate. However, the incidence of CRC is increasing among young people, especially adolescents and young adults (AYAs) who are not routinely screened. Although CRC is the fourth most common cancer among AYAs, it is extremely rare. In younger patients, CRC is often diagnosed later, and the proportion of patients with advanced CRC is higher than that in older patients. We herein present a case of poorly differentiated mucinous carcinoma of the ascending colon complicated by bilateral ovarian mature cystic teratomas (MCTs) in an AYA.

CASE PRESENTATION

A 17-year-old female patient presented with a chief complaint of abdominal pain and diarrhea that had persisted for more than 3 years. Colonoscopy revealed circumferential wall thickening of the ascending colon, and colonic biopsy revealed a mucous mass and findings of adenocarcinoma, predominantly signet ring cell carcinoma. Abdominal computed tomography (CT) and pelvic magnetic resonance imaging (MRI) showed bilateral ovarian tumors. Laparoscopic right hemicolectomy and enucleation of bilateral ovarian tumors were performed. Although the ascending colon cancer formed a large mass, there were no signs of peritoneal dissemination or direct invasion to the surrounding organs. Microscopically, the ascending colon was a poorly differentiated mucinous carcinoma with signet ring cell carcinoma and lymph node metastasis (9/42). The ovarian tumors were diagnosed as MCTs without any malignant components. The pathological diagnosis was ascending colon cancer (pT4aN2bM0, pStage IIIC) and bilateral ovarian MCTs. Microsatellite instability (MSI) testing was negative, and there were no gene mutations in either RAS or BRAF. Postoperative adjuvant chemotherapy with oxaliplatin and 5-FU was started.

CONCLUSIONS

We presented a case of locally advanced ascending colon cancer in a 17-year-old female patient. CRC rarely occurs in AYAs. However, the incidence has gradually increased in recent years. It should be considered as a differential diagnosis for young patients with long-term abdominal symptoms of unknown cause.

Cancer of colon, rectum and anus: the rising burden of disease worldwide from 1990 to 2019

BACKGROUND

Previous studies suggest that trends of cancer of colon, rectum and anus (CRA) incidence and mortality have been decreasing in recent decades. However, the trends are not uniform across age groups. This study aimed to assess the trends of the cancer of CRA burden worldwide.

METHODS

A descriptive study was carried out with a joinpoint regression analysis using the database of the Global Burden of Disease study.

RESULTS

About 2.2 million new cases of cancer of CRA were diagnosed in the world in 2019, whereby cancer of CRA caused ~1.1 million deaths. Globally, the incidence trend in both sexes together was increasing in 1990-2019, while the mortality trend was decreasing. The highest rise both in incidence and mortality was observed in the East Asia region (by 3.6% per year and by 1.4% per year, respectively) and the Andean Latin America region (by 2.7% per year and by 1.2% per year, respectively). However, of particular concern is the significant increase in the incidence (by 1.7% per year) and mortality (by 0.5% per year) from cancer of CRA in people aged 15-49.

CONCLUSIONS

Unfavorable trends in cancer of CRA in the young require more attention in management plans.

Ethnic diversity in treatment response for colorectal cancer: proof of concept for radiomics-driven enrichment trials

BACKGROUND

Several barriers hamper recruitment of diverse patient populations in multicenter clinical trials which determine efficacy of new systemic cancer therapies.

PURPOSE

We assessed if quantitative analysis of computed tomography (CT) scans of metastatic colorectal cancer (mCRC) patients using imaging features that predict overall survival (OS) can unravel the association between ethnicity and efficacy.

METHODS

We retrospectively analyzed CT images from 1584 mCRC patients in two phase III trials evaluating FOLFOX ± panitumumab (n = 331, 350) and FOLFIRI ± aflibercept (n = 437, 466) collected from August 2006 to March 2013. Primary and secondary endpoints compared RECIST1.1 response at month-2 and delta tumor volume at month-2, respectively. An ancillary study compared imaging phenotype using a peer-reviewed radiomics-signature combining 3 imaging features to predict OS landmarked from month-2. Analysis was stratified by ethnicity.

RESULTS

In total, 1584 patients were included (mean age, 60.25 ± 10.57 years; 969 men). Ethnicity was as follows: African (n = 50, 3.2%), Asian (n = 66, 4.2%), Caucasian (n = 1413, 89.2%), Latino (n = 27, 1.7%), Other (n = 28, 1.8%). Overall baseline tumor volume demonstrated Africans and Caucasians had more advanced disease (p < 0.001). Ethnicity was associated with treatment response. Response per RECIST1.1 at month-2 was distinct between ethnicities (p = 0.048) with higher response rate (55.6%) in Latinos. Overall delta tumor volume at month-2 demonstrated that Latino patients more likely experienced response to treatment (p = 0.021). Radiomics phenotype was also distinct in terms of tumor radiomics heterogeneity (p = 0.023).

CONCLUSION

This study highlights how clinical trials that inadequately represent minority groups may impact associated translational work. In appropriately powered studies, radiomics features may allow us to unravel associations between ethnicity and treatment efficacy, better elucidate mechanisms of resistance, and promote diversity in trials through predictive enrichment.

CLINICAL RELEVANCE STATEMENT

Radiomics could promote clinical trial diversity through predictive enrichment, hence benefit to historically underrepresented racial/ethnic groups that may respond variably to treatment due to socioeconomic factors and built environment, collectively referred to as social determinants of health.

KEY POINTS

•Findings indicate ethnicity was associated with treatment response across all 3 endpoints. First, response per RECIST1.1 at month-2 was distinct between ethnicities (p = 0.048) with higher response rate (55.6%) in Latinos. •Second, the overall delta tumor volume at month-2 demonstrated that Latino patients were more likely to experience response to treatment (p = 0.021). Radiomics phenotype was also distinct in terms of tumor radiomics heterogeneity (p = 0.023).

Development and validation of an online calculator to predict the pathological nature of colorectal tumors

BACKGROUND

No single endoscopic feature can reliably predict the pathological nature of colorectal tumors (CRTs).

AIM

To establish and validate a simple online calculator to predict the pathological nature of CRTs based on white-light endoscopy.

METHODS

This was a single-center study. During the identification stage, 530 consecutive patients with CRTs were enrolled from January 2015 to December 2021 as the derivation group. Logistic regression analysis was performed. A novel online calculator to predict the pathological nature of CRTs based on white-light images was established and verified internally. During the validation stage, two series of 110 images obtained using white-light endoscopy were distributed to 10 endoscopists [five highly experienced endoscopists and five less experienced endoscopists (LEEs)] for external validation before and after systematic training.

RESULTS

A total of 750 patients were included, with an average age of 63.6 ± 10.4 years. Early colorectal cancer (ECRC) was detected in 351 (46.8%) patients. Tumor size, left semicolon site, rectal site, acanthosis, depression and an uneven surface were independent risk factors for ECRC. The C-index of the ECRC calculator prediction model was 0.906 (P = 0.225, Hosmer–Lemeshow test). For the LEEs, significant improvement was made in the sensitivity, specificity and accuracy (57.6% vs 75.5%; 72.3% vs 82.4%; 64.2% vs 80.2%; P < 0.05), respectively, after training with the ECRC online calculator prediction model.

CONCLUSION

A novel online calculator including tumor size, location, acanthosis, depression, and uneven surface can accurately predict the pathological nature of ECRC.

Association Between the Immunohistochemistry Expression of E-cadherin, Beta-Catenin, and CD44 in Colorectal Adenocarcinoma

Background Colorectal cancer is a leading cause of cancer-related deaths worldwide, and epithelial-mesenchymal transition (EMT) plays an important role in cancer metastasis. In EMT, there is downregulation of E-cadherin, an intracellular adhesion molecule, as well as mutations in beta-catenin genes. On immunohistochemistry (IHC), the expression of CD44 portrays stem cell differentiation, which, in turn, is strongly associated with EMT. Thus, newer targeted therapies can be advised based on the expression of EMT and stem cell differentiation. Aims and objectives To determine the IHC expression of E-cadherin, beta-catenin, and CD44 in colorectal adenocarcinoma and find the association of the IHC expression of E-cadherin, beta-catenin, and CD44 with the histopathological grade, stage, lymph node metastasis, and lymphovascular invasion of colorectal adenocarcinoma. Materials and methods Fifty histologically proven cases of colorectal adenocarcinoma from 2016 to 2021 were included in this study, and clinicopathological data including age, gender, grading, TNM (tumour, node, and metastasis) staging, and lymph node metastasis were collected and hematoxylin and eosin slides were reviewed. IHC staining for E-cadherin, beta-catenin, and CD44 was done for all cases using the peroxidase and anti-peroxidase method, and the results were analysed. Results Peak incidence occurred in the 61-70 years age group (36%), and the most common site of the tumour was the rectal area (48%). The majority of the cases were in TNM stage II (37.3%), and a low expression of E-cadherin was found to be associated with higher T stage (p = 0.03), TNM staging (p = 0.04), as well as the presence of lymph node metastasis (p = 0.006). High beta-catenin expression was observed to have a significant correlation with a higher T stage (p = 0.006) and TNM staging (p = 0.005), while high CD44 expression was found to be associated with lymph node metastasis (p = 0.01). Altered expression of EMT-related proteins (E-cadherin and beta-catenin) showed a significant correlation with higher T stage (p = 0.03), TNM staging (p = 0.016), and lymph node metastasis (0.04). Conclusions EMT and cancer stem cell IHC markers are biomarkers for aggressive tumour growth and lymph node metastasis. Hence, EMT markers (E-cadherin and beta-catenin) and cancer stem cell markers (CD44) can be used as prognostic markers.

Use of 2-Stage Modeling to Identify How Colorectal Cancer Risk Changes With Period and Cohort

Colorectal cancer (CRC) incidence rates have decreased among adults aged 50 years or older while increasing in adults under age 50 years. Understanding these trends is challenging because of the multiple related time scales of age, diagnosis period, and birth cohort. We analyzed incidence rates of rectal, distal colon, and proximal colon cancer for individuals aged 20 years or more from the Surveillance, Epidemiology, and End Results Program for diagnosis years 1978-2017. We used a 2-stage generalized linear model to determine age, period, and cohort effects for CRC incidence. We first estimated birth cohort effects among people under age 45 years. We used these results to specify prior distributions for cohort effects in a Bayesian model to estimate period effects among people aged 45 years or more. There was no evidence of period effects for people under age 45 years. Risks of rectal and distal colon cancer increased for later birth cohorts. Compared with the 1943-1952 birth cohort, the 1983-1992 birth cohort had 2.2 times the risk of rectal cancer, 1.9 times the risk of distal colon cancer, and 1.3 times the risk of proximal colon cancer. For people aged ≥45 years, period effects showed declines in CRC risk that were attributable to screening.

Outcomes of open vs laparoscopic vs robotic vs transanal total mesorectal excision (TME) for rectal cancer: a network meta-analysis

BACKGROUND

Total mesorectal excision (TME) for rectal cancer can be achieved using open (OpTME), laparoscopic (LapTME), robotic (RoTME), or transanal techniques (TaTME). However, the optimal approach for access remains controversial. The aim of this network meta-analysis was to assess operative and oncological outcomes of all four surgical techniques.

METHODS

Ovid MEDLINE, EMBASE, and PubMed databases were searched systematically from inception to September 2020, for randomised controlled trials (RCTs) comparing any two TME surgical techniques. A network meta-analysis using a Bayesian random-effects framework and mixed treatment comparison was performed. Primary outcomes were the rate of clear circumferential resection margin (CRM), defined as > 1 mm from the closest tumour to the cut edge of the tissue, and completeness of mesorectal excision. Secondary outcomes included radial and distal resection margin distance, postoperative complications, locoregional recurrence, disease-free survival, and overall survival. Surface under cumulative ranking (SUCRA) was used to rank the relative effectiveness of each intervention for each outcome. The higher the SUCRA value, the higher the likelihood that the intervention is in the top rank or one of the top ranks.

RESULTS

Thirty-two RCTs with a total of 6151 patients were included. Compared with OpTME, there was no difference in the rates of clear CRM: LapTME RR = 0.99 (95% (Credible interval) CrI 0.97-1.0); RoTME RR = 1.0 (95% CrI 0.96-1.1); TaTME RR = 1.0 (95% CrI 0.96-1.1). There was no difference in the rates of complete mesorectal excision: LapTME RR = 0.98 (95% CrI 0.98-1.1); RoTME RR = 1.1 (95% CrI 0.98-1.4); TaTME RR = 1.0 (95% CrI 0.91-1.2). RoTME was associated with improved distal resection margin distance compared to other techniques (SUCRA 99%). LapTME had a higher rate of conversion to open surgery when compared with RoTME: RoTME RR = 0.23 (95% CrI 0.034-0.70). Length of stay was shortest in RoTME compared to other surgical approaches: OpTME mean difference in days (MD) 3.3 (95% CrI 0.12-6.0); LapTME MD 1.7 (95% CrI - 1.1-4.4); TaTME MD 1.3 (95% CrI - 5.2-7.4). There were no differences in 5-year overall survival (LapTME HR 1.1, 95% CrI 0.74, 1.4; TaTME HR 1.7, 95% CrI 0.79, 3.4), disease-free survival rates (LapTME HR 1.1, 95% CrI 0.76, 1.4; TaTME HR 1.1, 95% CrI 0.52, 2.4), or anastomotic leakage (LapTME RR = 0.92 (95% CrI 0.63, 1.1); RoTME RR = 1.0 (95% CrI 0.48, 1.8); TaTME RR = 0.53 (95% CrI 0.19, 1.2). The overall quality of evidence as per Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessments across all outcomes including primary and secondary outcomes was deemed low.

CONCLUSIONS

In selected patients eligible for a RCT, RoTME achieved improved distal resection margin distance and a shorter length of hospital stay. No other differences were observed in oncological or recovery parameters between (OpTME), laparoscopic (LapTME), robotic (RoTME), or trans-anal TME (TaTME). However, the overall quality of evidence across all outcomes was deemed low.

Colorectal cancer among farmers in the AGRICAN cohort study

OBJECTIVES

Specific farming types and tasks have rarely been studied in relation to colorectal cancer (CRC). We evaluated associations between 5 types of livestock and 13 types of crops in relation to CRC and its subsites within the Agriculture and Cancer (AGRICAN) study.

METHODS

AGRICAN cohort includes 181,842 agricultural workers living in 11 French geographical areas. Data on farming types and tasks was collected by self-administered questionnaires. We identified 2 609 CRC, 972 right colon, 689 left colon and 898 rectal incident cancer cases during follow-up from 2005 to 2015. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI).

RESULTS

Significantly increased CRC risk was observed for farmers producing horses (HR=1.18, 95% CI 1.06-1.31), sunflower (HR=1.23, 95% CI 1.03-1.45) and field vegetables (HR=1.18, 95% CI 1.02-1.36). Positive associations were also observed for pig, poultry and wheat/barley. Some associations were observed only for specific subsites: left colon cancer was associated with fruit growing (HR=1.36, 95% CI 1.09-1.70) and potato (HR=1.28, 95% CI 1.05-1.57). Tasks related to livestock (animal care, insecticide treatment, disinfection of milking equipment and building) or to crop (haymaking, sowing, pesticide treatment, seed treatment, harvesting) were also associated with CRC. Duration and size of farming types/task increased the risk for some of the associations. Analysis stratified by sex suggested an interaction with several farming types/task.

CONCLUSIONS

The current study showed original and positive findings for several farming types and tasks and CRC risk, overall and by subsites.

Incidence trends for twelve cancers in younger adults-a rapid review

Many cancer referral guidelines use patient’s age as a key criterium to decide who should be referred urgently. A recent rise in the incidence of colorectal cancer in younger adults has been described in high-income countries worldwide. Information on other cancers is more limited. The aim of this rapid review was to determine whether other cancers are also increasing in younger age groups, as this may have important implications for prioritising patients for investigation and referral. We searched MEDLINE, Embase and Web of Science for studies describing age-related incidence trends for colorectal, bladder, lung, oesophagus, pancreas, stomach, breast, ovarian, uterine, kidney and laryngeal cancer and myeloma. ‘Younger’ patients were defined based on NICE guidelines for cancer referral. Ninety-eight studies met the inclusion criteria. Findings show that the incidence of colorectal, breast, kidney, pancreas, uterine cancer is increasing in younger age groups, whilst the incidence of lung, laryngeal and bladder cancer is decreasing. Data for oesophageal, stomach, ovarian cancer and myeloma were inconclusive. Overall, this review provides evidence that some cancers are increasingly being diagnosed in younger age groups, although the mechanisms remain unclear. Cancer investigation and referral guidelines may need updating in light of these trends.

Changes in colorectal cancer incidence by site and age from 1973 to 2015: a SEER database analysis

Previous studies have reported incidence and mortality declines for colorectal cancer (CRC). We evaluated recent temporal trends of colorectal cancer in the United States for the last 4 decades. Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified primary CRCs diagnosed between 1973 and 2015. Temporal changes were evaluated by 6-year time periods. Age-adjusted incidence rates and annual percentage change (APC) for CRC were calculated by site and gender. Age-standardized relative survival rates were also evaluated. We identified 878,632 CRC patients, 51% of whom were men. For both genders, the proportions of new diagnoses of right-sided colon cancer (RCC) remained relatively stable, with the APC of - 0.8 and - 0.6 for the male and the female, respectively. There was a relative increase in RCC for the younger aged group (< 49 years). In contrast, the proportions of left-sided colon cancer (LCC) and rectosigmoid-cancer (RSC) decreased significantly over time. For those aged 0-49, the age adjusted incidence rates showed a small increase (in both genders), whereas age-adjusted incidence rates declined for those aged 50-64 and > 65 (in both genders). Our study showed near significance in the decline of CRC mortality rates in this population, except the 1-year age-standardized survival of LCC and RSC, and the 5-year age-standardized RCC in females. There was a significant increase in RCC for the younger aged group (< 49 years). In contrast, the proportions of LCC and RSC decreased significantly over time.

Colorectal Cancer: In the Pursuit of Health Equity

Colorectal cancer mortality has decreased considerably following the adoption of national screening programs, yet, within at-risk subgroups, there continue to be measurable differences in clinical outcomes from variations in screening, receipt of chemotherapy, radiation or surgery, access to clinical trials, research participation, and survivorship. These disparities are well-described and some have worsened over time. Disparities identified have included race and ethnicity, age (specifically young adults), socioeconomic status, insurance access, geography, and environmental exposures. In the context of the COVID-19 pandemic, colorectal cancer care has necessarily shifted dramatically, with broad, immediate uptake of telemedicine, transition to oral medications when feasible, and considerations for sequence of treatment. However, it has additionally marginalized patients with colorectal cancer with historically disparate cancer-specific outcomes; among them, uninsured, low-income, immigrant, and ethnic-minority patients-all of whom are more likely to become infected, be hospitalized, and die of either COVID-19 or colorectal cancer. Herein, we outline measurable disparities, review implemented solutions, and define strategies toward ensuring that all have a fair and just opportunity to be as healthy as possible.

The prognostic impact of RAS on overall survival following liver resection in early versus late-onset colorectal cancer patients

BACKGROUND

The impact of molecular aberrations on survival after resection of colorectal liver metastases (CLM) in patients with early-age-onset (EOCRC) versus late-age-onset colorectal cancer (LOCRC) is unknown.

METHODS

Patients who underwent liver resection for CLM with known RAS, BRAF and MSI status were retrospectively studied. The prognostic impact of RAS mutations by age was analysed with age as a categorical variable and a continuous variable.

RESULTS

The study included 573 patients, 192 with EOCRC and 381 with LOCRC. The younger the age of onset of CRC, the greater the negative impact on overall survival of RAS mutations in the LOCRC, EOCRC, and ≤40 years (hazard ratio (HR), 1.64 (95% confidence interval (CI), 1.23-2.20), 2.03 (95% CI, 1.30-3.17), and 2.97 (95% CI, 1.44-6.14), respectively. Age-specific mortality risk and linear regression analysis also demonstrated that RAS mutations had a greater impact on survival in EOCRC than in LOCRC (slope: -4.07, 95% CI -8.10 to 0.04, P = 0.047, R² = 0.08).

CONCLUSION

Among patients undergoing CLM resection, RAS mutations have a greater negative influence on survival in patients with EOCRC, more so in patients ≤40 years, than in patients with LOCRC and should be considered as a prognostic factor in multidisciplinary treatment planning.

Disparate and Alarming Impact of Gastrointestinal Cancers in Young Adult Patients

BACKGROUND

The rise in the incidence of gastric cancer (GC) and colorectal cancer (CRC) in young adults (YA) remains unexplained. We aim to identify differences in these malignancies between YA and older patients.

PATIENTS AND METHODS

We retrospectively analyzed the California Cancer Registry for all GC and CRC cases from 2000 to 2012. Pearson's Chi square analysis and stepwise regression model with backward elimination were used to analyze differences in demographic, clinical, and histopathologic features, and log-rank test to compare survival between young (≤ 40 years) and older adults (41-90 years) with GC or CRC, separately.

RESULTS

We analyzed 19,368 cases of GC and 117,415 cases of CRC. YA accounted for 4.6% of GC (n = 883) and 2.8% of CRC (n = 3273) patients. Compared with older patients, YA were more likely to be Hispanic (P < 0.0001) and have poorly differentiated (P < 0.0001), higher histologic grade (P < 0.0001), and signet ring features (P < 0.0001). Synchronous peritoneal metastases were more common in YA patients (32.1% vs. 14.1% GC, 8.8% vs. 5.4% CRC, P < 0.0001). The 5-year overall survival (OS) of YA with CRC or GC was longer than that of older patients with the same stage of malignancy; except YA with stage I GC, who demonstrated poor OS and disease-specific survival (DSS) (65.1% and 67.9%, respectively) which were significantly worse than those of adults aged 41-49 years (70.7% and 76.2%, respectively) and 50-64 years (69.1% and 78.1%, respectively).

CONCLUSIONS

YA with GC or CRC have distinctly worse clinical and histopathologic features compared with older patients and are disproportionately of Hispanic ethnicity. These results contribute to improving understanding of younger versus older GI cancer patients.

Trends in the epidemiology of young-onset colorectal cancer: a worldwide systematic review

BACKGROUND

Recent data suggest that the risk of young-onset colorectal cancer (yCRC), in adults less than 50 years of age, is increasing. To confirm findings and identify contemporary trends worldwide, we conducted a systematic review of studies examining population-level trends in yCRC epidemiology.

METHODS

We searched MEDLINE (1946-2018), EMBASE (1974-2018), CINAHL (1982-2018), and Cochrane Database of Systematic Reviews (2005-2018) for studies that used an epidemiologic design, assessed trends in yCRC incidence or prevalence, and published in English. Extracted information included country, age cut-off for yCRC, and reported trends in incidence or prevalence (e.g. annual percent change [APC]). We pooled similarly reported trend estimates using random effects models.

RESULTS

Our search yielded 8695 articles and after applying our inclusion criteria, we identified 40 studies from 12 countries across five continents. One study assessed yCRC prevalence trends reporting an APCp of + 2.6 and + 1.8 among 20-39 and 40-49 year olds, respectively. 39 studies assessed trends in yCRC incidence but with substantial variability in reporting. Meta-analysis of the most commonly reported trend estimate yielded a pooled overall APCi of + 1.33 (95% CI, 0.97 to 1.68; p < 0.0001) that is largely driven by findings from North America and Australia. Also contributing to these trends is the increasing risk of rectal cancer as among 14 studies assessing cancer site, nine showed an increased risk of rectal cancer in adults less than 50 years with APCi up to + 4.03 (p < 0.001).

CONCLUSIONS

Our systematic review highlights increasing yCRC risk in North America and Australia driven by rising rectal cancers in younger adults over the past two decades.

Evaluation of a Deep Neural Network for Automated Classification of Colorectal Polyps on Histopathologic Slides

IMPORTANCE

Histologic classification of colorectal polyps plays a critical role in screening for colorectal cancer and care of affected patients. An accurate and automated algorithm for the classification of colorectal polyps on digitized histopathologic slides could benefit practitioners and patients.

OBJECTIVE

To evaluate the performance and generalizability of a deep neural network for colorectal polyp classification on histopathologic slide images using a multi-institutional data set.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study used histopathologic slides collected from January 1, 2016, to June 31, 2016, from Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, with 326 slides used for training, 157 slides for an internal data set, and 25 for a validation set. For the external data set, 238 slides for 179 distinct patients were obtained from 24 institutions across 13 US states. Data analysis was performed from April 9 to November 23, 2019.

MAIN OUTCOMES AND MEASURES

Accuracy, sensitivity, and specificity of the model to classify 4 major colorectal polyp types: tubular adenoma, tubulovillous or villous adenoma, hyperplastic polyp, and sessile serrated adenoma. Performance was compared with that of local pathologists' at the point of care identified from corresponding pathology laboratories.

RESULTS

For the internal evaluation on the 157 slides with ground truth labels from 5 pathologists, the deep neural network had a mean accuracy of 93.5% (95% CI, 89.6%-97.4%) compared with local pathologists' accuracy of 91.4% (95% CI, 87.0%-95.8%). On the external test set of 238 slides with ground truth labels from 5 pathologists, the deep neural network achieved an accuracy of 87.0% (95% CI, 82.7%-91.3%), which was comparable with local pathologists' accuracy of 86.6% (95% CI, 82.3%-90.9%).

CONCLUSIONS AND RELEVANCE

The findings suggest that this model may assist pathologists by improving the diagnostic efficiency, reproducibility, and accuracy of colorectal cancer screenings.

Cumulative Burden of Colorectal Cancer-Associated Genetic Variants Is More Strongly Associated With Early-Onset vs Late-Onset Cancer

BACKGROUND & AIMS

Early-onset colorectal cancer (CRC, in persons younger than 50 years old) is increasing in incidence; yet, in the absence of a family history of CRC, this population lacks harmonized recommendations for prevention. We aimed to determine whether a polygenic risk score (PRS) developed from 95 CRC-associated common genetic risk variants was associated with risk for early-onset CRC.

METHODS

We studied risk for CRC associated with a weighted PRS in 12,197 participants younger than 50 years old vs 95,865 participants 50 years or older. PRS was calculated based on single nucleotide polymorphisms associated with CRC in a large-scale genome-wide association study as of January 2019. Participants were pooled from 3 large consortia that provided clinical and genotyping data: the Colon Cancer Family Registry, the Colorectal Transdisciplinary Study, and the Genetics and Epidemiology of Colorectal Cancer Consortium and were all of genetically defined European descent. Findings were replicated in an independent cohort of 72,573 participants.

RESULTS

Overall associations with CRC per standard deviation of PRS were significant for early-onset cancer, and were stronger compared with late-onset cancer (P for interaction = .01); when we compared the highest PRS quartile with the lowest, risk increased 3.7-fold for early-onset CRC (95% CI 3.28-4.24) vs 2.9-fold for late-onset CRC (95% CI 2.80-3.04). This association was strongest for participants without a first-degree family history of CRC (P for interaction = 5.61 × 10-5). When we compared the highest with the lowest quartiles in this group, risk increased 4.3-fold for early-onset CRC (95% CI 3.61-5.01) vs 2.9-fold for late-onset CRC (95% CI 2.70-3.00). Sensitivity analyses were consistent with these findings.

CONCLUSIONS

In an analysis of associations with CRC per standard deviation of PRS, we found the cumulative burden of CRC-associated common genetic variants to associate with early-onset cancer, and to be more strongly associated with early-onset than late-onset cancer, particularly in the absence of CRC family history. Analyses of PRS, along with environmental and lifestyle risk factors, might identify younger individuals who would benefit from preventive measures.

Characteristics of Advanced Colorectal Cancer Detected by Fecal Immunochemical Test Screening in Participants with a Negative Result the Previous Year

BACKGROUND

There is sufficient evidence to show the mortality reduction effect of colorectal cancer (CRC) screening programs using the fecal occult blood test (FOBT). However, we see cases that are found to be advanced CRC despite yearly FOBT screening.

METHODS

The aim of this study was to investigate the characteristics of advanced CRC detected by a fecal immunochemical test (FIT) screening program in participants with a negative screening result the previous year, which we call "Negative advanced CRC". A total of 109,639 participants (10.0% required colonoscopy, of whom 76.9% received one) underwent a CRC screening program using a FIT from fiscal 2009 to 2017. Negative advanced CRC was compared with advanced CRC (First advanced CRC) found at the first visit in a person who had not had a FIT screening history for more than 3 years. In addition, we compared the characteristics of Negative advanced CRC with those of interval cancer: cancer cases detected after a negative screening result and before the date of the next recommended screening.

RESULTS

A total of 339 cases of CRC (175 male: 164 female, 173 early stage: 166 advanced stage) were detected in the nine-year CRC screening period. The rate of right-sided CRCs was significantly higher in female (P < 0.01), advanced stage (P < 0.01), negative result previous year (P < 0.01), and symptom-negative (P < 0.01) participants than in each counterpart, respectively. The ratio of female (22/35; 62.9%) patients in Negative advanced CRCs tended to be high compared with that (40/83; 48.2%) in First advanced CRCs (P = 0.145). Overall, 22 (62.9%) of 35 Negative advanced CRCs and 28 (33.7%) of 83 First advanced CRCs were located in the right-sided colon, and the rate was significantly higher in Negative advanced CRCs (P < 0.01). In addition, the frequency of female patients was significantly higher in right-sided Negative advanced CRCs than in right-sided First advanced CRCs (P = 0.03).

CONCLUSION

The characteristics of Negative advanced CRC cases (female and right-sided colon) were similar to those of interval cancer reported so far. In the future, it will be necessary to introduce a screening program that is highly sensitive to right-sided CRC.

Young patients with benign anal diseases and rectal bleeding: should a colonoscopy be performed?

BACKGROUND AND AIM

There is no consensus whether a colonoscopy should be recommended for patients under 50 years of age who present with both anal bleeding and benign anal diseases. The aim of this study is to evaluate the effectiveness of colonoscopy to detect neoplastic lesions in this specific group of patients.

METHODS

A prospective study analyzing the results of colonoscopies performed in patients younger than 50 years of age who reported a rectal bleeding and also had a diagnosis of benign anal disease at first clinical visit.

RESULTS

One hundred and eighty-seven consecutive patients were prospectively included in this study. In 35 patients (18.7%), adenomatous polyps were diagnosed. Thirty-seven percent of those lesions (13 cases) were further classified as either advanced adenomas or serrated adenomas. The prevalence of adenomas was 14.6% among patients under the age of 40 and 20% among those between 40 and 50 years of age. Thirty-one percent of the adenomas (11 cases) were located in the right colon, without any other concomitant lesion in the distal colon. In addition, an unsuspected case of sigmoid carcinoma was diagnosed.

CONCLUSION

The performance of colonoscopy in young patients with benign anal diseases and hematochezia resulted in a high rate of detection of neoplastic lesions. The method might be considered as a valid strategy of investigation in this frequent clinical situation.

Changing trends in liver cancer incidence by race/ethnicity and sex in the US: 1992-2016

PURPOSE

Liver cancer incidence continues to increase while incidence of most other cancers is decreasing. We analyze recent and long-term trends of US liver cancer incidence by race/ethnicity and sex to best understand where to focus preventive efforts.

METHODS

Liver cancer incidence rates from 1992 to 2016 were obtained from the Surveillance, Epidemiology, and End Results registry. Delay-adjusted age-standardized incidence trends by race/ethnicity and sex were analyzed using joinpoint regression. Age-specific incidence was analyzed using age-period-cohort models. Hepatitis C seroprevalence by cohort was calculated using National Health and Nutrition Examination Survey data.

RESULTS

Liver cancer incidence has peaked in males and Asian or Pacific Islanders. Hispanic males, a high-incidence population, are experiencing a decrease in incidence, although not yet statistically significant. In contrast, incidence continues to increase in females, although at lower rates than in the 1990s, and American Indian/Alaska Natives (AI/ANs). Liver cancer incidence continues to be higher in males. Non-Hispanic Whites have the lowest incidence among racial/ethnic groups. Trends largely reflect differences in incidence by birth-cohort, which increased considerably, particularly in males, for those born around the 1950s, and continues to increase in females and AI/ANs. The patterns in males are likely driven by cohort variations in Hepatitis C infection.

CONCLUSIONS

Liver cancer incidence appears to have peaked among males. However, important differences in liver cancer trends by race/ethnicity and sex remain, highlighting the need for monitoring trends across different groups. Preventive interventions should focus on existing liver cancer disparities, targeting AI/ANs, females, and high-incidence groups.

Rectal cancer in the young: analysis of contributing factors and surgical outcomes

Background

Rectal cancer (RC) among young patients (≤50 years) is on the rise. The factors associated with development of RC are established however; factors leading to early RC remain unclear. The aim of this study was to assess factors associated with RC among young patients.

Methods

National estimates for patients with RC were abstracted from the National Inpatient Sample (NIS) database [2010-2012]. Patients were divided into two groups: young (≤50 years) and old (>50 years). Demographic, comorbidities, procedures performed, and hospital outcomes were collected. Regression analysis was performed to compare both groups.

Results

A total of 68,699 patients with RC were included. Incidence of RC among young patients increased significantly over the study period (2.4% vs. 3.4%; P=0.04). Majority of young patients with RC were white females. Bleeding was the most common presentation among young patients (P=0.03). Younger patients were more likely to have a family history of RC (P=0.01) and were more likely to undergo elective surgery (P=0.04) and laparoscopic surgery (P=0.02) compared to the older patients. Younger patients with RC were also more likely to use alcohol (P=0.03), be obese (P=0.02) compared to elder patients. There was no difference in the other co-morbidities between the two groups. After controlling for all factors in a regression model, younger patients had a lower complication rate (P=0.01), hospital LOS (P=0.02), and mortality rate (P=0.04).

Conclusions

RC in younger patients appears as a different disease with different outcomes. There appears to be multifactorial and environmental factors contributing to this trend. Race and gender also play a role in the incidence of RC in the young. Identifying these risk factors will lead to a more robust intervention plan to help improve care among younger patients with RC.

Reevaluation of a rightward shift in colorectal cancer: A single-center retrospective study in Tianjin

OBJECTIVES

Some Western reports have shown a proximal shift in colorectal cancer (CRC), but there are few studies in China. This study aimed to provide more information for the management and screening of CRC by investigating trends in the anatomic distribution of CRC among the Chinese population in recent years.

METHODS

A retrospective study was conducted on patients with CRC admitted to the Digestive Endoscopy Center of Tianjin Medical University General Hospital between January 2000 and December 2017. Patients were divided into a left-sided colorectal cancer (LSCRC) group and a right-sided colon cancer (RSCC) group. The detection rates of LSCRC and RSCC based on patients' age and sex, and on the time periods were analyzed.

RESULTS

A total of 2319 cases were diagnosed with CRC among 75 183 consecutive patients. The prevalence of CRC showed a significant reduction from 2000-2008 to 2009-2017 (3.8% vs 2.7%, P < .001). The proportion of RSCC presented a downtrend from 2000-2008 to 2009-2017 (40.6% vs 37.7%, P > .05). There were slightly more RSCCs in female patients than in male patients, with no significant difference (40.9% vs 36.5%, P > .05). The proportion of RSCC in patients aged ≥50 years was similar to that in younger patients. The alarming symptoms between LSCRC and RSCC showed a significant difference (P < .05).

CONCLUSIONS

In the present study, the prevalence of CRC declined significantly with time. However, there did not appear to be a rightward shift in CRC among the patients in Tianjin over the past 18 years.

Signet Ring Cell Carcinoma of the Colon in Young Adults: A Case Report and Literature Review

Colorectal cancer (CRC), one of the leading causes of cancer-related deaths, presents with challenging features related to its diagnosis and management. The incidence of CRC in the adolescent and young adult (AYA) population has increased over the past couple of decades despite the decline in the overall occurrence of CRC in the general population. Signet ring cell carcinoma is one of the rare histopathologic subtypes of CRC; however, it is more prevalent in AYA patients than in older adults and presents with unconventional histologic characteristics, a distinct clinical behavior, and a poor prognosis. We report a case of a primary signet ring cell adenocarcinoma of the ascending colon in a 19-year-old male who presented with unusual signs and symptoms and was diagnosed with stage IVA (T4a N0 M1, with peritoneal seeding). The unusual presentation and location of the tumor in this case warrant further investigation.

Colon cancer as a subsequent malignant neoplasm in young adults

BACKGROUND

The incidence of colon cancer (CC) is rising in younger adults and can occur de novo or in patients previously treated for another cancer. To the authors' knowledge, the impact on survival of CC occurring as a subsequent malignant neoplasm (SMN) has not been described for younger patients, which the authors anticipate to be lower with SMNs than that of primary CC.

METHODS

Patients aged <50 years with CC in the 2004 through 2014 National Cancer Data Base were identified. Patients were stratified by primary or subsequent occurrence. The impact of SMN status on overall survival (OS) was evaluated.

RESULTS

Of 41,915 patients, 2852 (6.8%) had colon SMNs. More patients with colon SMNs were aged 40 to 49 years compared with patients with primary CC (83% vs 77%; P < .001). Patients with colon SMNs presented with earlier clinical and pathological T, N, and M classifications (all P < .001). Colon SMNs more commonly occurred in the right colon, whereas primary CC was found to have a higher prevalence in the sigmoid colon (P < .001). Patients with colon SMNs more frequently underwent total colectomy (17% vs 5%; P < .001), but received less chemotherapy (53% vs 65%; P < .001). When adjusted for demographic, tumor, and treatment characteristics, SMN status was associated with a 23% decreased OS compared with primary CC (95% CI, 1.14-1.31; P < .001). Chemotherapy offered a 33% improvement in OS (95% CI, 0.56-0.8; P < .001).

CONCLUSIONS

Colon SMNs in younger patients present at an earlier stage and are treated more aggressively surgically compared with primary CCs. Patients with SMNs of the colon have decreased survival, although chemotherapy offers a survival advantage. Further investigation is warranted to determine whether these disparities are due to the effects of cancer treatment or differences in tumor biology.

Increased incidence of colon cancer among individuals younger than 50 years: A 17 years analysis from the cancer registry of the municipality of Milan, Italy

BACKGROUND

Colorectal cancer (CRC) overall incidence has been decreasing in the last decade. However, there is evidence of an increasing frequency of early-onset CRC in young individuals in several countries. The aim of this study is to evaluate the trends of CRC occurrence over 17 years in the municipality of Milan, Italy, focusing on early-onset CRC.

POPULATION AND METHODS

This retrospective study was performed using the Cancer Registry of the municipality of Milan, including all cases of CRC diagnosed 1999-2015. Incidence rates were stratified by age and anatomic subsite, and trends over time were measured using the estimated annual percentage change. Age-period-cohort modelling was used to disentangle the different effects.

RESULTS

18,783 cases of CRC were included. CRC incidence rates among individuals aged 50-60 years declined annually by 3% both in colon and in rectal cancer. Conversely, in adults younger than 50 years, overall CRC occurrence increased annually by 0.7%, with a diverging trend for colon (+2.6%) and rectal (-5.3%) cancer. Among individuals aged 60 years and older, CRC incidence rates increased by 1.0% annually up to 2007, and decrease thereafter by 4% per year, both for colon and rectal cancer. Age-period-cohort models showed a reduction of CRC risk for the cohorts born up to 1979, followed by an increase in younger cohorts. In contrast, rectal cancer among women showed a systematic risk decrease for all birth cohorts.

CONCLUSIONS

The study highlights increasing incidence of colon cancer in younger subjects and a decrease in incidence rates for rectal cancer in females.

Increasing Trend in Young-Onset Colorectal Cancer in Asia: More Cancers in Men and More Rectal Cancers

BACKGROUND

The incidence of young-onset colorectal cancer (CRC) is reported to be increasing in the Western world. There are no population-based studies assessing the trend across Asia.

METHODS

We performed a multinational cohort study involving four Asian countries/regions, namely Taiwan, Korea, Japan, and Hong Kong. The magnitude and direction of trend in the incidence of young-onset CRC (age < 50) were quantified using Joinpoint Regression Program to estimate average annual percentage change (AAPC).

RESULTS

In Taiwan (1995-2014), incidence of young-onset CRC significantly increased in both men (colon cancer: 4.9-9.7 per 100,000; rectal cancer: 4.0-8.3 per 100,000) and women (colon cancer: 5.1-9.7 per 100,000; rectal cancer: 3.8-6.4 per 100,000). In Korea (1999-2014), incidence of young-onset CRC significantly increased in both men (colon cancer: 5.0-10.4 per 100,000; rectal cancer: 4.9-14.0 per 100,000) and women (colon cancer: 4.1-9.6 per 100,000; rectal cancer: 4.1-9.1 per 100,000). The most pronounced change was observed with male rectal cancer, increasing by 3.9% per year in Taiwan (AAPC + 3.9, 95% confidence interval + 3.3 to +4.5, P < 0.05) and 6.0% per year in Korea (AAPC +6.0, 95% confidence interval + 4.5 to +7.6, P < 0.05). Only a significant increase in rectal cancer was noted in Japan (male rectal cancer: 7.2-10.1 per 100,000, female rectal cancer 4.7-6.7 per 100,000) and Hong Kong (male rectal cancer: 4.4-7.0 per 100,000).

CONCLUSIONS

Increasing trend in young-onset CRC is not limited to the Western world. This finding may have implications on screening program for CRC in these countries/regions.

Cancer statistics, 2019

Each year, the American Cancer Society estimates the numbers of new cancer cases and deaths that will occur in the United States and compiles the most recent data on cancer incidence, mortality, and survival. Incidence data, available through 2015, were collected by the Surveillance, Epidemiology, and End Results Program; the National Program of Cancer Registries; and the North American Association of Central Cancer Registries. Mortality data, available through 2016, were collected by the National Center for Health Statistics. In 2019, 1,762,450 new cancer cases and 606,880 cancer deaths are projected to occur in the United States. Over the past decade of data, the cancer incidence rate (2006-2015) was stable in women and declined by approximately 2% per year in men, whereas the cancer death rate (2007-2016) declined annually by 1.4% and 1.8%, respectively. The overall cancer death rate dropped continuously from 1991 to 2016 by a total of 27%, translating into approximately 2,629,200 fewer cancer deaths than would have been expected if death rates had remained at their peak. Although the racial gap in cancer mortality is slowly narrowing, socioeconomic inequalities are widening, with the most notable gaps for the most preventable cancers. For example, compared with the most affluent counties, mortality rates in the poorest counties were 2-fold higher for cervical cancer and 40% higher for male lung and liver cancers during 2012-2016. Some states are home to both the wealthiest and the poorest counties, suggesting the opportunity for more equitable dissemination of effective cancer prevention, early detection, and treatment strategies. A broader application of existing cancer control knowledge with an emphasis on disadvantaged groups would undoubtedly accelerate progress against cancer.

A blueprint for cancer screening and early detection: Advancing screening's contribution to cancer control

From the mid-20th century, accumulating evidence has supported the introduction of screening for cancers of the cervix, breast, colon and rectum, prostate (via shared decisions), and lung. The opportunity to detect and treat precursor lesions and invasive disease at a more favorable stage has contributed substantially to reduced incidence, morbidity, and mortality. However, as new discoveries portend advancements in technology and risk-based screening, we fail to fulfill the greatest potential of the existing technology, in terms of both full access among the target population and the delivery of state-of-the art care at each crucial step in the cascade of events that characterize successful cancer screening. There also is insufficient commitment to invest in the development of new technologies, incentivize the development of new ideas, and rapidly evaluate promising new technology. In this report, the authors summarize the status of cancer screening and propose a blueprint for the nation to further advance the contribution of screening to cancer control.

Incidence patterns of colorectal cancers in four countries of the Middle East Cancer Consortium (Cyprus, Jordan, Israel, and İzmir, Turkey) compared with those in the United States Surveillance, Epidemiology, and End Results Program

BACKGROUND/AIMS

There are wide variations in colorectal cancer (CRC) incidence across the world. Historically, the highest incidence rates have been reported historically in more developed countries; however, increasing trends have been seen in developing countries. Here, we present the CRC incidence pattern in Cyprus, Israel, Jordan, and İzmir, Turkey, which are countries of the Middle East Cancer Consortium (MECC).

MATERIALS AND METHODS

We analyzed 2005-2010 CRC data from population-based registries and calculated crude and age standardized rates for CRC, colon and rectum subsites, and annual percent changes (APCs) for trends.

RESULTS

The age-adjusted incidence rates (AAIRs) for CRC were the highest in Israeli Jews (IJ) (46.7 for males and 35.5 for females), which exceeded those of the USA Surveillance, Epidemiology, and End Result (SEER) program registries. In both sexes, AAIRs in Cyprus and Israeli Arabs (IA) were close to those in SEER registries. For both sexes, AAIRs in İzmir and Jordan were substantially lower than those in other registries. Statistically significant decreasing trends over time were observed in AAIRs for both sexes in the SEER program (APCs: males, -3.24% and females, -2.54%), whereas the trends varied within the MECC registries. There were decreasing AAIR trends for males in IJ and IA and for females in Cyprus and IJ; APC for females in IJ (-4.29%) was significant. Conversely, increasing trends with the significant APCs were observed in males in İzmir (2.43%) and Jordan (7.57%).

CONCLUSION

MECC countries comprise both high- and low-risk populations for CRCs. However, increasing trends in low-risk populations have been alarming. Thus, the need for implementing tailored primary and secondary prevention programs in the region is essential.

Characteristics of right-sided colonic neoplasia and colonoscopy barriers limiting their early detection and prognosis: a review of the literature

Colonoscopy provides less protection from colorectal cancer in the right colon than the left. Areas covered: This review examines patient outcomes and colonoscopy success rates to identify factors that limit the protective effect of colonoscopy in the right colon. The MEDLINE and Embase databases were searched for literature from 2000 onwards, on the long-term outcomes and differences in screening practice between the right and left colon. In total, 12 systematic reviews (including nine meta-analyses) and 44 primary data records were included. Differences in patient outcomes and colonoscopy practice were identified between the right and left colon, suggesting that several factors, many of which disproportionally affect the right colon, impact lesion detection rates. Shorter withdrawal times reduce detection rates, while longer times significantly increase detection; mostly of adenomas in the right colon. Colonoscope attachments often only show a significant improvement in detection rates in the right colon, suggesting detection is more challenging due to visibility of the right colonic mucosa. Higher bowel cleansing grades significantly improve detection rates in the right colon compared to the left. Expert commentary: These findings confirm the need for continued improvement of colonoscopy effectiveness, and obligatory quality assessment, overall and especially in the right colon.

Deregulation of methylation of transcribed-ultra conserved regions in colorectal cancer and their value for detection of adenomas and adenocarcinomas

Expression of Transcribed Ultraconserved Regions (T-UCRs) is often deregulated in cancer. The present study assesses the expression and methylation of three T-UCRs (Uc160, Uc283 and Uc346) in colorectal cancer (CRC) and explores the potential of T-UCR methylation in circulating DNA for the detection of adenomas and adenocarcinomas.

Expression levels of Uc160, Uc283 and Uc346 were lower in neoplastic tissues from 64 CRC patients (statistically significant for Uc160, p<0.001), compared to non-malignant tissues, while methylation levels displayed the inverse pattern (p<0.001, p=0.001 and p=0.004 respectively). In colon cancer cell lines, overexpression of Uc160 and Uc346 led to increased proliferation and migration rates. Methylation levels of Uc160 in plasma of 50 CRC, 59 adenoma patients, 40 healthy subjects and 12 patients with colon inflammation or diverticulosis predicted the presence of CRC with 35% sensitivity and 89% specificity (p=0.016), while methylation levels of the combination of all three T-UCRs resulted in 45% sensitivity and 74.3% specificity (p=0.013). In conclusion, studied T-UCRs’ expression and methylation status are deregulated in CRC while Uc160 and Uc346 appear to have a complicated role in CRC progression. Moreover their methylation status appears a promising non-invasive screening test for CRC, provided that the sensitivity of the assay is improved.

Incidence and mortality from colon and rectal cancer in Midwestern Brazil

Objective:

To describe the incidence and mortality rates from colon and rectal cancer in Midwestern Brazil.

Methods:

Data for the incidence rates were obtained from the Population-Based Cancer Registry (PBCR) according to the available period. Mortality data were obtained from the Mortality Information System (SIM) for the period between 1996 and 2008. Incidence and mortality rates were calculated by gender and age groups. Mortality trends were analyzed by the Joinpoint software. The age-period-cohort effects were calculated by the R software.

Results:

The incidence rates for colon cancer vary from 4.49 to 23.19/100,000, while mortality rates vary from 2.85 to 14.54/100,000. For rectal cancer, the incidence rates range from 1.25 to 11.18/100,000 and mortality rates range between 0.30 and 7.90/100,000. Colon cancer mortality trends showed an increase among males in Cuiabá, Campo Grande, and Goiania. For those aged under 50 years, the increased rate was 13.2% in Campo Grande. For those aged over 50 years, there was a significant increase in the mortality in all capitals. In Goiânia, rectal cancer mortality in males increased 7.3%. For females below 50 years of age in the city of Brasilia, there was an increase of 8.7%, while females over 50 years of age in Cuiaba showed an increase of 10%.

Conclusion:

There is limited data available on the incidence of colon and rectal cancer for the Midwest region of Brazil. Colon cancer mortality has generally increased for both genders, but similar data were not verified for rectal cancer. The findings presented herein demonstrate the necessity for organized screening programs for colon and rectal cancer in Midwestern Brazil.

Cancer statistics, 2018

Each year, the American Cancer Society estimates the numbers of new cancer cases and deaths that will occur in the United States and compiles the most recent data on cancer incidence, mortality, and survival. Incidence data, available through 2014, were collected by the Surveillance, Epidemiology, and End Results Program; the National Program of Cancer Registries; and the North American Association of Central Cancer Registries. Mortality data, available through 2015, were collected by the National Center for Health Statistics. In 2018, 1,735,350 new cancer cases and 609,640 cancer deaths are projected to occur in the United States. Over the past decade of data, the cancer incidence rate (2005-2014) was stable in women and declined by approximately 2% annually in men, while the cancer death rate (2006-2015) declined by about 1.5% annually in both men and women. The combined cancer death rate dropped continuously from 1991 to 2015 by a total of 26%, translating to approximately 2,378,600 fewer cancer deaths than would have been expected if death rates had remained at their peak. Of the 10 leading causes of death, only cancer declined from 2014 to 2015. In 2015, the cancer death rate was 14% higher in non-Hispanic blacks (NHBs) than non-Hispanic whites (NHWs) overall (death rate ratio [DRR], 1.14; 95% confidence interval [95% CI], 1.13-1.15), but the racial disparity was much larger for individuals aged <65 years (DRR, 1.31; 95% CI, 1.29-1.32) compared with those aged ≥65 years (DRR, 1.07; 95% CI, 1.06-1.09) and varied substantially by state. For example, the cancer death rate was lower in NHBs than NHWs in Massachusetts for all ages and in New York for individuals aged ≥65 years, whereas for those aged <65 years, it was 3 times higher in NHBs in the District of Columbia (DRR, 2.89; 95% CI, 2.16-3.91) and about 50% higher in Wisconsin (DRR, 1.78; 95% CI, 1.56-2.02), Kansas (DRR, 1.51; 95% CI, 1.25-1.81), Louisiana (DRR, 1.49; 95% CI, 1.38-1.60), Illinois (DRR, 1.48; 95% CI, 1.39-1.57), and California (DRR, 1.45; 95% CI, 1.38-1.54). Larger racial inequalities in young and middle-aged adults probably partly reflect less access to high-quality health care. CA Cancer J Clin 2018;68:7-30. © 2018 American Cancer Society.

Differences in Cancer-Specific Mortality of Right- Versus Left-Sided Colon Adenocarcinoma: A Surveillance, Epidemiology, and End Results Database Analysis

Purpose

Studies have shown an increased risk for all-cause mortality with right-sided colon cancer (RCC) as compared with left-sided colon cancer (LCC). However, these studies were unable to directly account for mortality events unrelated to cancer, known as other-cause mortality. We investigated the difference in cancer-specific mortality (CSM) between RCC and LCC at localized, regional, and metastatic stages, according to the Fine and Gray proportional hazards model, while accounting for other-cause mortality as a competing risk.

Methods

Using the SEER database, we identified 90,635 patients with LCC (ie, involving the splenic flexure, descending, sigmoid, and rectosigmoid colon) and 112,679 patients with RCC (ie, involving the cecum, ascending, hepatic flexure, and transverse colon) diagnosed from 1998 to 2013. We performed a competing risk analysis for CSM using the Fine and Gray proportional hazard model, adjusting for age, sex, race, tumor grade, surgery status, year of diagnosis, and tumor laterality, with two-sided testing and a statistical significance threshold of 0.05.

Results

Compared with LCC, RCC demonstrated statistically significant decreased CSM at the localized stage (adjusted hazards ratio [AHR], 0.865; P < .001), equivalent CSM at the regional stage (AHR, 0.990; P = .440), and increased CSM at the metastatic stage (AHR, 1.175; P < .001).

Conclusion

Using a competing risk model, we have shown that RCC, compared with LCC, is associated with lower CSM at the localized stage, equivalent CSM at the regional stage, and higher CSM at the metastatic stage. This pattern may correlate with variation in genetic factors, including known decreased prevalence of microsatellite instability in RCC with regional and metastatic disease.

Decrease in Incidence of Colorectal Cancer Among Individuals 50 Years or Older After Recommendations for Population-based Screening

BACKGROUND & AIMS

The incidence of colorectal cancer (CRC) in the United States is increasing among adults younger than 50 years, but incidence has decreased among older populations after population-based screening was recommended in the late 1980s. Blacks have higher incidence than whites. These patterns have prompted suggestions to lower the screening age for average-risk populations or in blacks. At the same time, there has been controversy over whether reductions in CRC incidence can be attributed to screening. We examined age-related and race-related differences in CRC incidence during a 40-year time period.

METHODS

We determined the age-standardized incidence of CRC from 1975 through 2013 by using the population-based Surveillance, Epidemiology, and End Results (SEER) program of cancer registries. We calculated incidence for 5-year age categories (20-24 years through 80-84 years and 85 years or older) for different time periods (1975-1979, 1980-1984, 1985-1989, 1990-1994, 1995-1999, 2000-2004, 2005-2009, and 2010-2013), tumor subsite (proximal colon, descending colon, and rectum), and stages at diagnosis (localized, regional, and distant). Analyses were stratified by race (white vs black).

RESULTS

There were 450,682 incident cases of CRC reported to the SEER registries during the entire period (1975-2013). Overall incidence was 75.5/100,000 white persons and 83.6/100,000 black persons. CRC incidence peaked during 1980 through 1989 and began to decrease in 1990. In whites and blacks, the decreases in incidence between the time periods of 1980-1984 and 2010-2013 were limited to the screening-age population (ages 50 years or older). Between these time periods, there was 40% decrease in incidence among whites compared with 26% decrease in incidence among blacks. Decreases in incidence were greater for cancers of the distal colon and rectum, and reductions in these cancers were greater among whites than blacks. CRC incidence among persons younger than 50 years decreased slightly between 1975-1979 and 1990. However, among persons 20-49 years old, CRC incidence increased from 8.3/100,000 persons in 1990-1994 to 11.4/100,000 persons in 2010-2013; incidence rates in younger adults were similar for whites and blacks.

CONCLUSIONS

On the basis of an analysis of the SEER cancer registries from 1975 through 2013, CRC incidence decreased only among individuals 50 years or older between the time periods of 1980-1984 and 2010-2013. Incidence increased modestly among individuals 20-49 years old between the time periods of 1990-1994 and 2010-2013. The decision of whether to recommend screening for younger populations requires a formal analysis of risks and benefits. Our observed trends provide compelling evidence that screening has had an important role in reducing CRC incidence.

The Dietary Inflammatory Index Is Associated with Colorectal Cancer Risk in the Multiethnic Cohort

Background: Diet is known to influence systemic inflammation, a recognized risk factor for colorectal cancer (CRC). Studies in ethnically diverse populations that examine the association between dietary inflammatory potential and CRC incidence are limited.Objectives: We used the Dietary Inflammatory Index to clarify the relation between the inflammatory potential of diet and CRC incidence across racial/ethnic groups. We hypothesized that proinflammatory diets would be associated with an increased risk of CRC, and that these associations may differ across racial/ethnic groups.Methods: The Multiethnic Cohort (MEC) follows a prospective study design. It includes 190,963 white, African-American, native Hawaiian, Japanese-American, and Latino men and women aged 45-75 y at recruitment and followed over 20 y. Participants completed a food frequency questionnaire from which energy-adjusted Dietary Inflammatory Index (E-DII) scores were computed and categorized into quartiles. CRC incidence was documented through linkage to cancer registry programs. Cox proportional hazards regression was used to estimate HRs and 95% CIs, adjusting for known or expected CRC risk factors.Results: Among all participants, more-proinflammatory diets (highest quartile compared with lowest quartile) were associated with an increased risk of CRC (HR: 1.21; 95% CI: 1.11, 1.32). However, the effect size was larger for men (HR: 1.28; 95% CI: 1.13, 1.45) than for women (HR: 1.16; 95% CI: 1.02, 1.33), although the interaction term for sex was not statistically significant (P-interaction = 0.17). When stratified by race/ethnicity, the association was significantly different between groups for men (P-interaction = 0.01), although not for women (P-interaction = 0.20). Significant associations with HRs ranging from 2.33 to 1.04 were observed in white, Japanese-American, and Latino men, and native Hawaiian women.Conclusions: Overall, more-proinflammatory diets, as identified by the E-DII, were associated with increased CRC risk in MEC participants across racial/ethnic groups. This study adds to the evidence suggesting that diets with high proinflammatory potential may increase CRC risk.

Comparative effectiveness of screening strategies for colorectal cancer

BACKGROUND

Screening for colorectal cancer (CRC) has been successful in decreasing the incidence and mortality from CRC. Although new screening tests have become available, their relative impact on CRC outcomes remains unexplored. This study compares the outcomes of various screening strategies on CRC outcomes.

METHODS

A Markov model representing the natural history of CRC was built and validated against empiric data from screening trials as well as the Microstimulation Screening Analysis (MISCAN) model. Thirteen screening strategies based on colonoscopy, sigmoidoscopy, computed tomographic colonography, as well as fecal immunochemical, occult blood, and stool DNA testing were compared with no screening. A simulated sample of the US general population ages 50 to 75 years with an average risk of CRC was followed for up to 35 years or until death. Effectiveness was measured by discounted life years gained and the number of CRCs prevented. Discounted costs and cost-effectiveness ratios were calculated. A discount rate of 3% was used in calculations. The study took a societal perspective.

RESULTS

Colonoscopy emerged as the most effective screening strategy with the highest life years gained (0.022 life years) and CRCs prevented (n = 1068) and the lowest total costs ($2861). These values were 0.012 life years gained, 574 CRCs prevented, and a total cost of $3164, respectively, for FOBT; and 0.011 life years gained, 647 CRCs prevented, and a total cost of $4296, respectively, for DNA testing. Improved sensitivity or specificity of a screening test for CRC detection was not sufficient to close the outcomes gap compared with colonoscopy.

CONCLUSIONS

Improvement in CRC-detection performance is not sufficient to improve screening outcomes. Special attention must be directed to detecting precancerous adenomas. Cancer 2017;123:1516-1527. © 2017 American Cancer Society.

Cancer Statistics, 2017

Each year, the American Cancer Society estimates the numbers of new cancer cases and deaths that will occur in the United States in the current year and compiles the most recent data on cancer incidence, mortality, and survival. Incidence data were collected by the Surveillance, Epidemiology, and End Results Program; the National Program of Cancer Registries; and the North American Association of Central Cancer Registries. Mortality data were collected by the National Center for Health Statistics. In 2017, 1,688,780 new cancer cases and 600,920 cancer deaths are projected to occur in the United States. For all sites combined, the cancer incidence rate is 20% higher in men than in women, while the cancer death rate is 40% higher. However, sex disparities vary by cancer type. For example, thyroid cancer incidence rates are 3-fold higher in women than in men (21 vs 7 per 100,000 population), despite equivalent death rates (0.5 per 100,000 population), largely reflecting sex differences in the "epidemic of diagnosis." Over the past decade of available data, the overall cancer incidence rate (2004-2013) was stable in women and declined by approximately 2% annually in men, while the cancer death rate (2005-2014) declined by about 1.5% annually in both men and women. From 1991 to 2014, the overall cancer death rate dropped 25%, translating to approximately 2,143,200 fewer cancer deaths than would have been expected if death rates had remained at their peak. Although the cancer death rate was 15% higher in blacks than in whites in 2014, increasing access to care as a result of the Patient Protection and Affordable Care Act may expedite the narrowing racial gap; from 2010 to 2015, the proportion of blacks who were uninsured halved, from 21% to 11%, as it did for Hispanics (31% to 16%). Gains in coverage for traditionally underserved Americans will facilitate the broader application of existing cancer control knowledge across every segment of the population. CA Cancer J Clin 2017;67:7-30. © 2017 American Cancer Society.

Colorectal cancer incidence and survival by sub-site and stage of diagnosis: a population-based study at the advent of national screening

BACKGROUND

The location and staging of a colorectal cancer (CRC) determine prognosis and choice of treatment. We examined the sub-site, sex, and stage distribution for CRC in Ireland for patients diagnosed in the period immediately prior to the implementation of a national screening programme.

METHODS

Incident cases of CRC were abstracted from the National Cancer Registry for the period 1994-2012 (n = 38,912). Incidence proportions and 3-year cancer-related survival were calculated.

RESULTS

The incidence of CRC during 2010-2012 averaged 1021 females and 1424 males per year. While the overall incidence rate of CRC was static during 1994-2012, this masked a significant increase in the rate of proximal colon tumours (+1.3 % per year), a decreases in the rate of tumours of overlapping/colon NOS (-2.2 % per year), and no change in the rates of cancers of the distal colon and rectosigmoid junction (RSJ)/rectum. Proximal tumours occurred more frequently in females (F vs. M, 38 vs. 29 %), in older persons and increased over time. Compared to distal colon tumours, proximal colon [RR risk ratio 1.08, 95 % CI (1.05, 1.10)] and RSJ/rectum tumours [RR 1.08 (1.05, 1.11)] were more likely to be diagnosed at late stage. The proportion of late-stage tumours increased steadily over five diagnosis periods [e.g., 1994-1997 (51 %) vs. 2010-2012 (57 %), RR 1.12 (1.08, 1.16)]. Cancer survival improved over four diagnosis periods.

CONCLUSIONS

There was a distal-to-proximal shift and a trend towards diagnosis at late stage during 1994-2012. Some reversal of this trend is expected following the implementation of a national screening programme.

CA11-19: a tumor marker for the detection of colorectal cancer

BACKGROUND AND AIM

Colorectal cancer (CRC) remains the second most frequent cause of cancer deaths in the United States. Blood tests using tumor-related antigens aid in diagnosing CRC. However, higher sensitivity and specificity are needed before an acceptable tumor antigen blood test for CRC is clinically useful. This study describes the diagnostic accuracy of an enzyme-linked immunosorbent assay for the CA11-19 serologic tumor antigen for the detection of CRC.

METHODS

Serum specimens were obtained from 522 colonoscopy-confirmed subjects in institutional review board-approved studies. Specimens were blind coded. CA11-19 levels were determined by using enzyme-linked immunosorbent assay analysis. The results were tabulated for categories of normal, hyperplastic polyps, benign GI, adenomatous polyps, and CRC based on their final diagnosis.

RESULTS

When a cutoff of 6.4 units/mL for normal is used, the CA11-19 level was elevated in 128 of 131 of CRC subjects, for an observed sensitivity of 98% (95% confidence interval, 93.1%-99.5%). Normal levels were found in 87% of normal subjects (90/103) and 83% of those with benign GI diseases (185/223). When combined, this yields an observed specificity of 84% (95% confidence interval, 80.0%-87.9%).

CONCLUSION

CA11-19 is a serologic tumor marker for the diagnosis of CRC with a sensitivity of 98% and specificity of 84%. This high sensitivity means that this test will detect 43 of 44 cases of CRC presented. For those older than 50 years of age, it has a positive predictive value of 3.6% and a negative predictive value of 99.98%. Additional prospective studies are needed to further clarify the use of CA11-19 as an aid in the diagnosis of CRC.

Cancer statistics, 2016

Each year, the American Cancer Society estimates the numbers of new cancer cases and deaths that will occur in the United States in the current year and compiles the most recent data on cancer incidence, mortality, and survival. Incidence data were collected by the National Cancer Institute (Surveillance, Epidemiology, and End Results [SEER] Program), the Centers for Disease Control and Prevention (National Program of Cancer Registries), and the North American Association of Central Cancer Registries. Mortality data were collected by the National Center for Health Statistics. In 2016, 1,685,210 new cancer cases and 595,690 cancer deaths are projected to occur in the United States. Overall cancer incidence trends (13 oldest SEER registries) are stable in women, but declining by 3.1% per year in men (from 2009-2012), much of which is because of recent rapid declines in prostate cancer diagnoses. The cancer death rate has dropped by 23% since 1991, translating to more than 1.7 million deaths averted through 2012. Despite this progress, death rates are increasing for cancers of the liver, pancreas, and uterine corpus, and cancer is now the leading cause of death in 21 states, primarily due to exceptionally large reductions in death from heart disease. Among children and adolescents (aged birth-19 years), brain cancer has surpassed leukemia as the leading cause of cancer death because of the dramatic therapeutic advances against leukemia. Accelerating progress against cancer requires both increased national investment in cancer research and the application of existing cancer control knowledge across all segments of the population.

A Systematic Review and Network Meta-Analysis of Biologic Agents in the First Line Setting for Advanced Colorectal Cancer

Background

Epithelial growth factor receptor inhibitors (EGFRis) and bevacizumab (BEV) are used in combination with chemotherapy for the treatment of metastatic colorectal cancer (mCRC). However, few randomized controlled trials (RCTs) have directly compared their relative efficacy on progression-free survival (PFS) and overall survival (OS).

Methods

We conducted a systematic review of first-line RCTs comparing (1) EGFRis vs. BEV, with chemotherapy in both arms (2) EGFRis + chemotherapy vs. chemotherapy alone, or (3) BEV + chemotherapy vs. chemotherapy alone, using Cochrane methodology. Data on and PFS and OS were extracted using the Parmar method. Pairwise meta-analyses and Bayesian network meta-analyses (NMA) were conducted to estimate the direct, indirect and combined PFS and OS hazard ratios (HRs) comparing EGFRis to BEV.

Results

Seventeen RCTs contained extractable data for quantitative analysis. Combining direct and indirect data using an NMA did not show a statistical difference between EGFRis versus BEV (PFS HR = 1.11 (95% CR: 0.92–1.36) and OS HR = 0.91 (95% CR: 0.75–1.09)). Direct meta-analysis (3 RCTs), indirect (14 RCTs) and combined (17 RCTs) NMA of PFS HRs were concordant and did not show a difference between EGFRis and BEV. Meta-analysis of OS using direct evidence, largely influenced by one trial, showed an improvement with EGFRis therapy (HR = 0.79 (95% CR: 0.65–0.98)), while indirect and combined NMA of OS did not show a difference between EGFRis and BEV Successive inclusions of trials over time in the combined NMA did not show superiority of EGFRis over BEV.

Conclusions

Our findings did not support OS or PFS benefits of EGFRis over BEV in first-line mCRC.

Characterization of the Hispanic or latino population in health research: a systematic review

The size and diversity of the Hispanic population in the United States has dramatically increased, with vast implications for health research. We conducted a systematic review of the characterization of the Hispanic population in health research and described its implications. Relevant studies were identified by searches of PubMed, Embase Scopus, and Science/Social Sciences Citation Index from 2000 to 2011. 131 articles met criteria. 56% of the articles reported only "Hispanic" or "Latino" as the characteristic of the Hispanic research population while no other characteristics were reported. 29% of the articles reported language, 27% detailed country of origin and 2% provided the breakdown of race. There is great inconsistency in reported characteristics of Hispanics in health research. The lack of detailed characterization of this population ultimately creates roadblocks in translating evidence into practice when providing care to the large and increasingly diverse Hispanic population in the US.

Increasing Trend in Colorectal Cancer Incidence in the Southeast of Iran 2003-2013: A Population Based Cancer Registry Study

Rates based on age-adjusted incidence of colorectal cancers over a 10-year period in Kerman, the biggest province of Iran, were estimated from 2003 to 2013. Data were obtained from the population-based cancer registry unit of Kerman University of Medical Sciences (CR-KMU). Information included age, sex, city, ICD-O and year of registry. Our trend analyses cover 3.91% of the Iranian population. The data set comprised cases diagnosed from 2003 to 2013.The population of over 20 years was interpolated using 2003 and 2010 censuses. Then, truncated age-adjusted incidence rates were calculated. Increase was noted from 2003-2009 to 2010-2013 for 731 cancer cases considered in the analysis. The increases was most prominent in 2009. Totally, the frequency of the cancer was greater in males. Moreover, calculating truncated age-adjusted incidence rate indicated that the most prevalent age of colorectal incidence was in the 50-59 year age group except in 2007-2008 and 2012- 2013, when greatest incidences occurred in people aged 60-69 years. Our data revealed that the incidence rates of colorectal cancer have increased over the past decade in our region of Iran.

Increasing disparities in the age-related incidences of colon and rectal cancers in the United States, 1975-2010

IMPORTANCE

The overall incidence of colorectal cancer (CRC) has been decreasing since 1998 but there has been an apparent increase in the incidence of CRC in young adults.

OBJECTIVE

To evaluate age-related disparities in secular trends in CRC incidence in the United States.

DESIGN, SETTING, AND PATIENTS

A retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) CRC registry. Age at diagnosis was analyzed in 15-year intervals starting at the age of 20 years. SEER*Stat was used to obtain the annual cancer incidence rates, annual percentage change, and corresponding P values for the secular trends. Data were obtained from the National Cancer Institute's SEER registry for all patients diagnosed as having colon or rectal cancer from January 1, 1975, through December 31, 2010 (N = 393 241).

MAIN OUTCOME AND MEASURE

Difference in CRC incidence by age.

RESULTS

The overall age-adjusted CRC incidence rate decreased by 0.92% (95% CI, -1.14 to -0.70) between 1975 and 2010. There has been a steady decline in the incidence of CRC in patients age 50 years or older, but the opposite trend has been observed for young adults. For patients 20 to 34 years, the incidence rates of localized, regional, and distant colon and rectal cancers have increased. An increasing incidence rate was also observed for patients with rectal cancer aged 35 to 49 years. Based on current trends, in 2030, the incidence rates for colon and rectal cancers will increase by 90.0% and 124.2%, respectively, for patients 20 to 34 years and by 27.7% and 46.0%, respectively, for patients 35 to 49 years.

CONCLUSIONS AND RELEVANCE

There has been a significant increase in the incidence of CRC diagnosed in young adults, with a decline in older patients. Further studies are needed to determine the cause for these trends and identify potential preventive and early detection strategies.

Predictors of Colorectal Cancer Screening: Does Rurality Play a Role?

PURPOSE

The purpose of this study was to explore the associations between sociodemographic factors such as residence, health care access, and colorectal cancer (CRC) screening among residents of Texas.

METHODS

Using the 2012 Behavioral Risk Factor Surveillance Survey, we performed logistic regression analyses to determine predictors of CRC screening among Texas residents, including rural versus urban differences. Our outcomes of interest were previous (1) CRC screening using any CRC test, (2) fecal occult blood test (FOBT), or (3) endoscopy, as well as up-to-date screening using (4) any CRC test, (5) FOBT, or (6) endoscopy. The independent variable of interest was rural versus urban residence; we controlled for other sociodemographic and health care access variables such as lack of health insurance.

RESULTS

Multivariate analysis showed that individuals who were residents of a rural/non-Metropolitan Statistical Area (MSA) location (OR = 0.70, 95% CI = 0.51-0.97) or a suburban county (OR = 0.61, 95% CI = 0.39-0.95) were less likely to report ever having any CRC screening compared to residents of a center city of an MSA. Residents of a rural/non-MSA location were less likely (OR = 0.49, 95% CI = 0.28-0.87) than residents of a center city of an MSA to be up-to-date using FOBT. There was decreased likelihood of ever being screened for CRC among the uninsured (OR = 0.43, 95% CI = 0.31-0.59).

CONCLUSIONS

Effective development and implementation of strategies to improve screening rates should aim at improving access to health care, taking into account demographic characteristics such as rural versus urban residence.