Trends in colorectal incidence by anatomic subsite from 1985 to 2005: a population-based study

Effectiveness of Colonoscopy Screening vs Sigmoidoscopy Screening in Colorectal Cancer

Importance

Randomized clinical screening trials have shown that sigmoidoscopy screening reduces colorectal cancer (CRC) incidence and mortality. Colonoscopy has largely replaced sigmoidoscopy for CRC screening, but long-term results from randomized trials on colonoscopy screening are still lacking.

Objective

To estimate the additional screening benefit of colonoscopy compared with sigmoidoscopy.

Design, Setting, and Participants

This comparative effectiveness simulation study pooled data on 358 204 men and women randomly assigned to sigmoidoscopy screening or usual care in 4 randomized sigmoidoscopy screening trials conducted in Norway, Italy, the US, and UK with inclusion periods in the years 1993 to 2001. The primary analysis of the study was conducted from January 19 to December 30, 2021.

Intervention

Invitation to endoscopic screening.

Main Outcomes and Measures

Primary outcomes were CRC incidence and mortality. Using pooled 15-year follow-up data, colonoscopy screening effectiveness was estimated assuming that the efficacy of colonoscopy in the proximal colon was similar to that observed in the distal colon in the sigmoidoscopy screening trials. The simulation model was validated using data from Norwegian participants in a colonoscopy screening trial.

Results

This analysis included 358 204 individuals (181 971 women [51%]) aged 55 to 64 years at inclusion with a median follow-up time ranging from 15 to 17 years. Compared with usual care, colonoscopy prevented an estimated 50 (95% CI, 42-58) CRC cases per 100 000 person-years, corresponding to 30% incidence reduction (rate ratio, 0.70 [95% CI, 0.66-0.75]), and prevented an estimated 15 (95% CI, 11-19) CRC deaths per 100 000 person-years, corresponding to 32% mortality reduction (rate ratio, 0.68 [95% CI, 0.61-0.76]). The additional benefit of colonoscopy screening compared with sigmoidoscopy was 12 (95% CI, 10-14) fewer CRC cases and 4 (95% CI, 3-5) fewer CRC deaths per 100 000 person-years, corresponding to percentage point reductions of 6.9 (95% CI, 6.0-7.9) for CRC incidence and 7.6 (95% CI, 5.7-9.6) for CRC mortality. The number needed to switch from sigmoidoscopy to colonoscopy screening was 560 (95% CI, 486-661) to prevent 1 CRC case and 1611 (95% CI, 1275-2188) to prevent 1 CRC death.

Conclusions and Relevance

The findings of this comparative effectiveness study assessing long-term follow-up after CRC screening suggest that there was an additional preventive effect on CRC incidence and mortality associated with colonoscopy screening compared with sigmoidoscopy screening, but the additional preventive effect was less than what was achieved by introducing sigmoidoscopy screening where no screening existed. The results probably represent the upper limit of what may be achieved with colonoscopy screening compared with sigmoidoscopy screening.

RAS Mutations Predict Recurrence-Free Survival and Recurrence Patterns in Colon Cancer: A Unicenter Study in Morocco

PURPOSE

To date, only a few studies have investigated the role of molecular alterations in cancer recurrence. This exploratory study aimed to evaluate the impact of molecular alterations on the time and site of recurrence in patients with stage I-IV CRC and to identify the risk factors predicting recurrence-free survival in colon cancer.

METHODS

A total of 270 patients were retrospectively included. We assessed the full RAS status using Sanger and pyrosequencing. MSI status was determined by immunohistochemical analysis. Molecular alterations were correlated with recurrence timing (early or late), recurrence patterns, and recurrence-free survival. Statistical analysis was performed using the Kaplan-Meier method and the log-rank test.

RESULTS

Of the 270 patients, 85 (31%) experienced recurrence, among whom 53% had mutant full RAS status, 48% had KRAS mutations, and 31.4% had KRAS p. G12V mutation subtype. Compared with those with late recurrence, patients with early recurrence were significantly older (P = 0.02) and more likely to have poorly differentiated tumors, a higher rate of positive lymph nodes, KRAS mutations, and especially KRAS p. G12V mutation variant. RAS mutation status, KRAS mutations, and rare mutations are more common in patients with lung cancer recurrence. Multivariate logistic regression analysis revealed that differentiation, perineural invasion, full RAS mutation status, and KRAS codon 13 mutations were independent factors for recurrence-free survival in colon cancer.

CONCLUSION

In this cohort, the timing and patterns of recurrence appeared to be associated with the patient's molecular profile. KRAS codon 12 mutations were the worst predictors of recurrence-free survival at all stages in our population.

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

Background

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

Methods

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

Results

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

Conclusion

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

15-Year Benefits of Sigmoidoscopy Screening on Colorectal Cancer Incidence and Mortality : A Pooled Analysis of Randomized Trials

BACKGROUND

The effectiveness of screening for colorectal cancer (CRC) by sex and age in randomized trials is uncertain.

OBJECTIVE

To evaluate the 15-year effect of sigmoidoscopy screening on CRC incidence and mortality.

DESIGN

Pooled analysis of 4 large-scale randomized trials of sigmoidoscopy screening.

SETTING

Norway, the United States, the United Kingdom, and Italy.

PARTICIPANTS

Women and men aged 55 to 64 years at enrollment.

INTERVENTION

Sigmoidoscopy screening.

MEASUREMENTS

Primary end points were cumulative incidence rate ratio (IRR) and mortality rate ratio (MRR) and rate differences after 15 years of follow-up comparing screening versus usual care in intention-to-treat analyses. Stratified analyses were done by sex, cancer site, and age at screening.

RESULTS

Analyses comprised 274 952 persons (50.7% women), 137 493 in the screening and 137 459 in the usual care group. Screening attendance was 58% to 84%. After 15 years, the rate difference for CRC incidence was 0.51 cases (95% CI, 0.40 to 0.63 cases) per 100 persons and the IRR was 0.79 (CI, 0.75 to 0.83). The rate difference for CRC mortality was 0.13 deaths (CI, 0.07 to 0.19 deaths) per 100 persons, and the MRR was 0.80 (CI, 0.72 to 0.88). Women had less benefit from screening than men for CRC incidence (IRR for women, 0.84 [CI, 0.77 to 0.91]; IRR for men, 0.75 [CI, 0.70 to 0.81]; P = 0.032 for difference) and mortality (MRR for women, 0.91 [CI, 0.77 to 1.17]; MRR for men, 0.73 [CI, 0.64 to 0.83]; P = 0.025 for difference). There was no statistically significant difference in screening effect between persons aged 55 to 59 years and those aged 60 to 64 years.

LIMITATION

Data from the U.K. trial were less granular because of privacy regulations.

CONCLUSION

This pooled analysis of all large randomized trials of sigmoidoscopy screening demonstrates a significant and sustained effect of sigmoidoscopy on CRC incidence and mortality for 15 years.

PRIMARY FUNDING SOURCE

Health Fund of South-East Norway.

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

Background

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

Methods

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

Results

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

Conclusion

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

Supplementary Information

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

Long-Term Follow-up of the Italian Flexible Sigmoidoscopy Screening Trial

BACKGROUND

Recent reports showed that the protective effect of flexible sigmoidoscopy (FS) screening was maintained up to17 years, although differences were reported by sex.

OBJECTIVE

To assess long-term reduction of colorectal cancer (CRC) incidence and mortality after a single FS screening.

DESIGN

Parallel randomized controlled trial. (ISRCTN registry number: 27814061).

SETTING

6 centers in Italy.

PARTICIPANTS

Persons aged 55 to 64 years expressing interest in having FS screening if invited, recruited from 1995 to 1999 and followed until 2012 (incidence) and 2014 to 2016 (mortality).

INTERVENTION

Eligible persons were randomly assigned (1:1 ratio) to either the once-only FS screening group or control (usual care) group.

MEASUREMENTS

Incidence and mortality rate ratios (RRs) and rate differences.

RESULTS

A total of 34 272 persons (17 136 in each group) were included in the analysis; 9911 participants had screening in the intervention group. Median follow-up was 15.4 years for incidence and 18.8 years for mortality. Incidence of CRC was reduced by 19% (RR, 0.81 [95% CI, 0.71 to 0.93]) in the intention-to-treat (ITT) analysis, comparing the intervention with the control group, and by 33% (RR, 0.67 [CI, 0.56 to 0.81]) in the per protocol (PP) analysis, comparing participants screened in the intervention group with the control persons. Colorectal cancer mortality was reduced by 22% (RR, 0.78 [CI, 0.61 to 0.98]) in the ITT analysis and by 39% (RR, 0.61 [CI, 0.44 to 0.84]) in the PP analysis. Incidence of CRC was statistically significantly reduced among both men and women. Colorectal cancer mortality was statistically significantly reduced among men (ITT RR, 0.73 [CI, 0.54 to 0.97]) but not among women (ITT RR, 0.90 [CI, 0.59 to 1.37]).

LIMITATION

Self-selection of volunteers from the general population sample targeted for recruitment may limit generalizability.

CONCLUSION

The strong protective effect of a single FS screening for CRC incidence and mortality was maintained up to 15 and 19 years, respectively.

PRIMARY FUNDING SOURCE

Italian Association for Cancer Research, Italian National Research Council, Istituto Oncologico Romagnolo, Fondo "E. Tempia," University of Milan, and Local Health Unit ASL-Torino.

A clinical study of newly-diagnosed colorectal cancer over 2 years in a gastroenterology center in Iraq

Background and study aims Colorectal cancer (CRC) is the most common gastrointestinal cancer and the third most commonly diagnosed malignancy affecting about one million individuals each year. The etiology for most cases of CRC appears to be related to environmental factors. This study to describe the main characteristics of this malignancy regarding age, gender, and anatomical sub site distribution, as well as the main presenting symptoms in Iraqi patients.

Patients and methods Patients with newly-diagnosed CRC by colonoscopy findings and confirmed by histopathological examination of endoscopic colonic biopsies were studied.

Results Sixty three cases with a newly-diagnosed CRC were included in this study. There were 31 (49.2%) males and 32 (50.8%) females. CRC peaked in the 60–69 years old age group (p < 0.05), more than 60% were between 40 and 69 years old. Fresh bleeding per rectum was the most common symptom occurred in 48 (76.2%) patients; while the least common was weight loss (19%). The mean duration of symptoms before referral was 7.3 ± 12.6 months. The tumor sites of the CRC were the rectum and sigmoid region seen in 77.8% (p < 0.05), the rectum alone reported in 37 patients (58.7%); followed by sigmoid colon in 12 (19%) patients, cecum in 7 (11.1%) patients and the ascending colon seen in 2 (3.2%) patients.

Conclusions In this study CRC occurs in relatively younger age groups in comparison to studies in the developed countries with rectal cancer predominates of all colorectal cancers.

Colorectal cancer screening: The surgery rates they are a-changing. A nationwide study on surgical resections in Italy

BACKGROUND

Growing evidence suggests that colorectal cancer (CRC) screening based on the fecal immunochemical test (FIT) reduces CRC incidence and surgical resection rates.

AIMS

To compare trends in surgery for proximal and distal CRC among Italian regions at different stages of screening implementation.

METHODS

From the National Hospital Discharge Database we selected hospitalizations with CRC resection of residents aged 50-74 years during 2002-2014, and computed surgery rates for the 8 most populous Italian regions with/without a screening program.

RESULTS

In regions with screening, implemented around 2006-2007, the annual percent change (APC) of distal CRC resection was +1.7 (95% confidence interval -1.0, 4.4) during 2002-2007 and -9.1 (-10.6, -7.7) during 2007-2014. No significant change was observed in regions without screening. The APC for proximal colon resection in regions with screening was +5.8 (2.5, 9.0) during 2002-2007 and -4.1 (-5.8, -2.4) during 2007-2014, while in regions without screening surgical rates increased through the whole study period. Compared to 2002, in 2014 distal CRC resection rates were greatly reduced in regions with screening, reaching values similar to proximal CRC resection.

CONCLUSION

Following the implementation of screening programs surgery rates steeply decreased, confirming the deep impact of FIT-based screening on the burden of CRC.

Detection of serrated lesions in proximal colon by simulated sigmoidoscopy vs faecal immunochemical testing in a multicentre, pragmatic, randomised controlled trial

Background

The diagnostic yield of the faecal immunochemical test and sigmoidoscopy in detecting proximal serrated polyps in a colorectal cancer screening programme has not been fully assessed.

Aim

We determined the detection rate of proximal serrated polyps by simulated sigmoidoscopy and faecal immunochemical test compared with total colonoscopy in a population-based, multicentre, nationwide, randomised controlled trial (ColonPrev study).

Methods

Sigmoidoscopy yield was simulated based on the UK-Flexible Sigmoidoscopy Trial for total colonoscopy referral. Definitions were: proximal serrated polyp (proximal serrated polyp): sessile serrated polyp or hyperplastic polyp of any size and proximal at-risk serrated polyp (at-risk proximal serrated polyp): sessile serrated polyp of any size or hyperplastic polyp ≥ 10 mm, both located proximally to the splenic flexure.

Results

A total of 10,611 individuals underwent faecal immunochemical test and 5059 underwent total colonoscopy and were evaluated by simulated sigmoidoscopy. Sigmoidoscopy and faecal immunochemical test were less accurate in detecting proximal serrated polyps (odds ratio: 0.13; 95% confidence interval: 0.10-0.18 and 0.13; 0.09-0.18, p < 0.0001, respectively). Both tests were inferior to colonoscopy in detecting at-risk proximal serrated polyps, and sigmoidoscopy was inferior to faecal immunochemical test in detecting these lesions (odds ratio: 0.17; 95% confidence interval: 0.10-0.30 and 0.25; 0.17-0.37, p < 0.0001, respectively).

Conclusion

Sigmoidoscopy and faecal immunochemical test are less accurate in detecting proximal serrated polyps than colonoscopy, particularly in women.

Colorectal cancer survival at an oncologic center in Colombia. A historic cohort study

INTRODUCTION AND AIMS

In Colombia, cancer of the colon is the third most frequent cancer in relation to incidence and mortality. Five-year survival depends on stage at diagnosis, albeit that rate is not known for the country. The aim of the present study was to characterize the overall survival and disease-free survival rates in an adult population with colorectal cancer treated at an oncology center in Medellín, Colombia.

MATERIALS AND METHODS

A retrospective cohort study was conducted. The case records of patients with a histologic diagnosis of colorectal cancer, seen within the time frame of 2011 and 2015, were reviewed. The overall survival and disease-free survival curves were calculated using the Kaplan-Meier method.

RESULTS

A total of 824 (54.9%) patients with cancer of the colon and 676 (45.1%) with cancer of the rectum were treated. Mean patient age was 63.3 years, female sex predominated (56.3%), and 98.1% of the tumors were adenocarcinomas. The majority of the lesions were stage iii (31.9% in the colon and 35.5% in the rectum) at the time of diagnosis. Surgery was the most frequent treatment in the colon (85.2%) and radiotherapy was the most frequent in the rectum (75.4%). Overall survival at the median follow-up (27.3 months) was 66.7% for cancer of the colon and 63.9% for cancer of the rectum. Disease-free survival at the median follow-up (18.6 months in colon and 14.9 in rectum) was 72.5 and 68.9%, respectively.

CONCLUSIONS

The clinical characteristics and treatment of patients were similar to those found in other studies. Two-year survival was higher than in other Colombian reports and 5-year survival was lower than that observed in developed countries.

Variable Endoscopist performance in proximal and distal adenoma detection during colonoscopy: a retrospective cohort study

BACKGROUND

Adenoma Detection Rate (ADR) is a validated colonoscopy quality indicator. In addition to overall ADR, Distal and Proximal Adenoma Detection Rates may provide important colonoscopy quality information. The goal of this study is to determine the association between distal and proximal adenoma detection (AD) and to identify factors contributing to overall, distal, and proximal AD.

METHODS

This is a retrospective cohort study of patients with a noted family history of CRC or positive fecal occult blood test who underwent a screening colonoscopy at a regional colorectal cancer (CRC) screening center between May 2009 and December 2011. Data regarding patient demographics, procedure details, endoscopist characteristics and polyp histology were captured. The main outcomes measured were overall, distal, and proximal AD.

RESULTS

1907 patients were included. The median age was 60 years and 42% were male. Endoscopist median overall ADR was 25% (30% male, 21% female). Endoscopist distal ADR was only modestly associated with their proximal ADR (Spearman Rank: 0.51 p = 0.11). Highest overall ADR (29 to 45%) was found for endoscopists whose distal and proximal ADRs were above the group median. In multivariate analysis, factors associated with overall, distal, and proximal AD included age, sex, and endoscopist practicing experience.

CONCLUSION

Inclusion of distal and proximal ADRs, in addition to overall ADR, in colonoscopy quality assessment provides the more accurate feedback on endoscopist performance.

Gastrointestinal Bleeding Due to Gastrointestinal Tract Malignancy: Natural History, Management, and Outcomes

BACKGROUND

Gastrointestinal (GI) tumor bleeding can vary from occult bleeding to massive hemorrhage and can be the presenting sign of malignancy.

AIMS

Our primary aims were to: (1) characterize the natural history, treatment, and outcomes in patients with GI tumor bleeding and (2) compare and contrast bleeding in upper GI (UGI)/small bowel (SB) and lower GI malignancies.

METHODS

Patients with endoscopically confirmed tumor bleeding were identified through search of consecutive electronic medical records: Bleeding was determined by the presence of melena, hematochezia, hematemesis, or fecal occult blood. Comprehensive clinical and management data were abstracted.

RESULTS

A total of 354 patients with GI tumors were identified: 71 had tumor bleeding (42 UGI/SB and 29 colonic). GI bleeding was the initial presenting symptom of malignancy in 55/71 (77%) of patients; 26/71 patients had widely metastatic disease at presentation. Further, 15 of 26 patients with metastatic disease presented with GI bleeding. Visible bleeding was present in 14/42 (33%) and 4/29 (14%) of UGI/SB and colonic tumors, respectively. Endoscopic hemostasis was attempted in 10 patients, and although initial control was successful in all, bleeding recurred in all of these patients. The most common endoscopic lesion was clean-based tumor ulceration. Overall mortality at 1 year was 57% for esophageal/gastric, 14% for SB, and 33% for colonic tumors.

CONCLUSIONS

When patients with GI malignancy present with GI bleeding, it is often the index symptom. Initial endoscopic hemostasis is often successful, but rebleeding is typical. Esophageal and gastric tumors carry the poorest prognosis, with a high 1-year mortality rate.

Effectiveness of flexible sigmoidoscopy screening in men and women and different age groups: pooled analysis of randomised trials

OBJECTIVE

 To compare the effectiveness of flexible sigmoidoscopy in screening for colorectal cancer by patient sex and age.

DESIGN

 Pooled analysis of randomised trials (the US Prostate, Lung, Colorectal and Ovarian cancer screening trial (PLCO), the Italian Screening for Colon and Rectum trial (SCORE), and the Norwegian Colorectal Cancer Prevention trial (NORCCAP)).

DATA SOURCES

 Aggregated data were pooled from each randomised trial on incidence of colorectal cancer and mortality stratified by sex, age at screening, and colon subsite (distal v proximal).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

 Invited individuals aged 55-74 (PLCO), 55-64 (SCORE), and 50-64 (NORCCAP). Individuals were randomised to receive flexible sigmoidoscopy screening once only (SCORE and NORCCAP) or twice (PLCO), or receive usual care (no intervention).

RESULTS

 287 928 individuals were included in the pooled analysis; 115 139 randomised to screening and 172 789 to usual care. Compliance rates were 58%, 63%, and 87% in SCORE, NORCCAP, and PLCO, respectively. Median follow-up was 10.5 to 12.1 years. Screening reduced the incidence of colorectal cancer in men (relative risk 0.76; 95% confidence interval 0.70 to 0.83) and women (0.83; 0.75 to 0.92). No difference in the effect of screening was seen between men younger than 60 and those older than 60. Screening reduced the incidence of colorectal cancer in women younger than 60 (relative risk 0.71; 95% confidence interval 0.59 to 0.84), but not significantly in those aged 60 or older (0.90; 0.80 to 1.02). Colorectal cancer mortality was significantly reduced in both younger and older men, and in women younger than 60. Screening reduced colorectal cancer incidence to a similar extent in the distal colon in men and women, but there was no effect of screening in the proximal colon in older women with a significant interaction between sex and age group (P=0.04).

CONCLUSION

 Flexible sigmoidoscopy is an effective tool for colorectal cancer screening in men and younger women. The benefit is smaller and not statistically significant for women aged over 60; alternative screening methods that more effectively detect proximal tumours should be considered for these women.

Comparative analysis of endoscopic and histopathological features of superficial elevated lesions resected by endoscopic mucosal resection in the distal and proximal colon

OBJECTIVE

to compare endoscopic and histopathologic features of superficial, elevated lesions with one or more centimeters in diameter, diagnosed by videocolonoscopy on the distal and proximal colon, and subjected to mucosal resection.

METHODS

we conducted a retrospective, cross-sectional, observational study involving 8,075 videocolonoscopies. From this total, we evaluated 166 mucosectomies in 145 patients with superficial, elevated lesions with a diameter equal to or greater than 1cm.

RESULTS

the lesion prevalence was lower in G1 than in G2 (34.9% vs. 65%). The mean age, gender distribution and size (1.9cm in G1 versus 2.0cm in G2, p=0.921) were similar. There was no difference of mucosal surfaces in relation to the location (p=0.575). Considering Intraepithelial neoplasias, both the low grade, high grade (including carcinomas) and hyperplasic ones showedd no difference (p=0.527), nor did the neoplastic lesions when divided into serrated and non-serrated (p=0.124). Excluding 13 hyperplastic lesions and two carcinomas, 124 (82.1%) were non-serrated and 27 (17.9%), serrated.

CONCLUSION

were found no significant differences between endoscopic and histopathological aspects of superficial, elevated lesions of 1cm or more in diameter in distal colon compared with the proximal, when resected by mucosectomy. Although not significant, there was a tendency of association between the location of the lesion and the presence of serrated features.

OBJETIVO

comparar aspectos endoscópicos e histopatológicos de lesões superficialmente elevadas, com um ou mais centímetros de diâmetro, diagnosticadas por videocolonoscopias e ressecadas por mucosectomias do cólon distal com as do cólon proximal.

MÉTODOS

estudo foi retrospectivo, transversal, observacional, envolvendo 8075 videocolonoscopias. Avaliou-se 166 mucosectomias em 145 pacientes com lesões superficialmente elevadas com diâmetro igual ou maior do que 1cm.

RESULTADOS

a prevalência de lesões foi menor no G1 do que no G2 (34,9% x 65%). A média de idade, a distribuição por sexo e o tamanho (1,9cm no G1 e 2cm no G2, p=0,921) foram semelhantes. Não houve diferenças das superfícies em relação à localização (p=0,575). Considerando neoplasia intraepitelial de baixo grau, neoplasia intraepitelial de alto grau (incluindo carcinomas) e hiperplásicas, não houve diferença (p=0,527), assim como quando foram divididas as lesões neoplásicas em serrilhadas e não serrilhadas (p=0,124). Excluindo-se 13 lesões hiperplásicas e duas com carcinomas, 124 (82,1%) foram não serrilhadas e 27 (17,9%) serrilhadas.

CONCLUSÃO

não foram observadas diferenças significativas entre os aspectos endoscópicos e os histopatológicos das lesões superficialmente elevadas, com 1cm ou mais de diâmetro, ressecadas por mucosectomia do cólon distal em relação ao proximal. Embora não significante, há tendência à associação entre a localização da lesão e a presença de características serrilhadas.

Incidence trends and age distribution of colorectal cancer by subsite in Guangzhou, 2000-2011

Introduction

Colorectal cancer (CRC) is the third most common cancer in China. The incidence of CRC has been increasing in recent years. The aim of this study was to explore the incidence trends and the age distribution of CRC by subsite in Guangzhou between 2000 and 2011.

Methods

A total of 22,432 incident cases of CRC between 2000 and 2011 from Guangzhou Cancer Registry were identified. Crude incidence and age-standardized rates (ASRs), using the Segi’s world standard population, were calculated for CRC and CRC subsites. The incidence trend was analyzed and the annual percentage change (APC) in incidence was calculated by using JoinPoint software.

Results

The crude incidence increased significantly from 23.4/10⁵ in 2000 to 37.4/10⁵ in 2011 for males and from 20.9/10⁵ to 30.5/10⁵ for females. The ASRs of CRC incidence stabilized during the period of 2000–2011 for both males and females. The ages at the onset of CRC for both males and females during 2010–2011 were significantly higher compared with those during 2000–2002 (males: t = 1.95, P = 0.05; females: t = 6.03, P < 0.01). For males aged 50–64 years, the CRC incidence increased by 8.50% annually (P = 0.04) during 2000–2004 and by 1.68% annually (P = 0.03) during 2005–2011. For females aged 65 years and older, the CRC incidence increased by 5.77% annually (P = 0.03) during 2000–2004. There were no significant changes for the CRC incidences in males aged 49 and younger and 65 years and older and females aged 64 years and younger during 2000–2004, or for those in all females as well as males aged 49 years and younger and 65 years and older during 2005–2011. The percentage of colon cancer in all CRCs increased significantly for both males and females between the periods of 2000–2002 and 2010–2011. The ASRs of descending colon and sigmoid colon cancer incidences increased significantly for females during 2005–2011 (APC, 5.51% and 1.08%, respectively, both P < 0.05).

Conclusions

The crude incidence of CRC increased significantly between 2000 and 2011 because of the aging, whereas the ASRs kept stable. The percentage of colon cancer in all CRCs increased significantly. Further surveillance, research, and intervention are needed to identify the causes of these changes and to reduce the incidence and mortality of CRC.

Spatial modeling of colonic lesions with geographic information systems

BACKGROUND

Geographic information system (GIS) software has been used in health care systems to display and analyze spatial pattern of diseases and health services.

OBJECTIVES

This study was performed to assess spatial patterns of colon's pathologic lesions based on the pathologic reports and assess whether it is possible to use GIS software in health services.

PATIENTS AND METHODS

Archives of pathology of Namazi and Faghihi hospitals, two main referral centers of south-west of Iran, were obtained and reviewed between January 2009 and September 2011 for biopsy reports of patients who underwent colonoscopy. Abnormal biopsies were categorized into five different subgroups according to the type of pathologic specimens. By GIS, spatial patterns of colon biopsies were plotted in different maps and spatial auto-correlation of colon biopsies was calculated using the Moran's Index.

RESULTS

A total of 4815 biopsies from 2663 different patients were reviewed, 53.8% of which were men. Abnormal biopsies were 2781 of all specimens (57.8%). Neoplastic lesions, inflammatory bowel diseases and polyps were 9.3%, 19.3% and 29.2% of total biopsies, respectively. Pathologic biopsies were more common in the distal colon. Maps of all biopsies and maps of specific pathologies were manifested in GIS.

CONCLUSIONS

Our study showed that left-sided lesions are still more common in the Iranian population. On the other hand, surveying the right side of colon is as important as the distal part, which necessitates total colonoscopy.

Patient age and duration of colonoscopy are predictors for adenoma detection in both proximal and distal colon

AIM: To investigate the relation of patient characteristics and procedural parameters to the endoscopic detection rate of colonic adenomas. Further to study, which factors may be capable to predict the localization of adenomatous lesions.

METHODS: We used the data base of a prospective randomized colonoscopy study (The ColoCap trial) to identify patients being diagnosed with colon adenoma. Logistic regression analysis was conducted to reveal predictors for adenoma detection in the entire colon and also with respect to the proximal and distal part. Covariates including age, gender, duration of colonoscopy and comorbidities were defined to determine association between predictors and adenoma detection.

RESULTS: Equal numbers of adenomas were detected in the proximal and distal side of the splenic flexure [126 (57%) vs 94 (43%), P = 0.104]. Simultaneous occurrence of adenomas in both sides of the colon was rare. The appearance of both proximal and distal adenoma was associated with increasing age (P = 0.008 and P = 0.024) and increasing duration of colonoscopy (P < 0.001 and P = 0.001). Male gender was a predictor for adenoma detection in the proximal colon (P = 0.008) but statistical significance was slightly missed with respect to the distal colon (P = 0.089). Alcohol abuse was found to be a predictor for the detection of distal adenoma (P = 0.041).

CONCLUSION: Increasing age and longer duration of colonoscopy are factors with a strong impact on adenoma detection both in the proximal and distal colon. Since proximal adenomas occurred in absence of distal adenomas, complete colonoscopy should be performed for screening.

Long-fragment DNA as a potential marker for stool-based detection of colorectal cancer

Neoplastic cells that are exfoliated from the colorectal epithelium exhibit dysfunctional apoptotic mechanisms, and thus it is possible to identify high-molecular-weight DNA fragments (long DNA) in feces. In the present study, the sensitivity and specificity of fecal-based long DNA assays were evaluated for the detection of colorectal cancer (CRC). Feces were collected from 54 healthy volunteers and 130 patients with CRC prior to surgical treatment. The presence of long DNA of the adenomatosis polyposis coli, Kirsten rat sarcoma viral oncogene homolog (KRAS), B-raf proto-oncogene, serine/threonine kinase and p53 genes was assessed by polymerase chain reaction followed by electrophoresis. The identification of long DNA in feces was found to exhibit a sensitivity of 56.2% and specificity of 96.3% for CRC detection. In addition, long DNA was identified in the feces of 58/90 (64.4%) patients with distal CRC and 15/40 (37.5%) patients with proximal CRC. This study indicates the potential of the fecal long DNA assay as a non-invasive and easily performed method for the detection of individuals with CRC.

Microangiopathy is common in submucosal vessels of the colon in patients with diabetes mellitus

OBJECTIVES

The pathophysiology behind gastrointestinal dysmotility in diabetes mellitus is unknown. Both esophageal dysmotility and gastroparesis have been shown to be associated with retinopathy, suggesting that microangiopathy is important in the common etiology. The aim of the present study was to examine whether patients with diabetes exhibit microangiopathy in the colon, and if present, to correlate microangiopathy with the clinical picture.

METHODS

Consecutive patients subjected to colon surgery were identified in the southernmost districts of Skåne between January 2011 and May 2013. Medical records were scrutinized, and patients with a history of diabetes were noted. Gender, age, type of diabetes, treatment, complications, and other concomitant diseases were registered. Histopathologic re-evaluation of surgical biopsies with morphometric analyses of submucosal vessels in the colon was performed. Morphometric examination and clinical data were compared with non-diabetic patients.

RESULTS

Of 1135 identified patients during the time period studied, 95 patients with diabetes were recognized and included. Fifty-three non-diabetic, randomly chosen patients served as controls. The mean age was 71.8 ± 10.2 and 71.4 ± 9.5 years in diabetic and non-diabetic patients, respectively. Microangiopathy was found in 68.4% of diabetic patients and in 7.5% of non-diabetic patients (p < 0.001). The wall-to-lumen ratio was 0.31 (0.23-0.46) in patients with diabetes compared with 0.16 (0.12-0.21) in non-diabetic patients (p < 0.001). No clinical association with microangiopathy could be verified.

CONCLUSION

Microangiopathy in the colon is more common in diabetic than in non-diabetic patients. The clinical significance of microangopathy has yet to be clarified.

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

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

Colorectal cancer: Histopathologic differences in tumor characteristics between patients with and without diabetes

BACKGROUND

Current literature suggests that diabetes is a possible predictor of risk and worse outcome in colorectal cancer (CRC). The objective of this study was to explore if there are histopathologic differences in CRC between populations with and without diabetes.

PATIENTS AND METHODS

Retrospective analysis was done on 534 patients with CRC. Patients were divided into diabetic and nondiabetic subgroups. Data were collected for lymphovascular invasion, tumor location, depth invasion, staging, level of differentiation, histologic type, and presence of tumor components (mucinous, signet ring, or neuroendocrine).

RESULTS

Univariately, patients with diabetes had deeper tumor invasion, greater lymphovascular invasion, and higher TNM staging (OR and 95% CI, 2.06 [1.37, 3.10], 2.52 [1.74, 3.63], and 2.45 [1.70, 3.52], respectively; P < .001). Covariate adjustment retained the significant effect of diabetes on tumor characteristics (P < .005). Multivariable adjustment significantly linked diabetes with signet ring cell carcinoma (log odds, 11.40 ± 5.28; P = .03) and tumor components (log odds, 0.58 ± 0.25; P = .02). Patients with diabetes with hyperlipidemia had more well-differentiated tumors (log odds, -0.96 ± 0.47; P = .04). Transverse tumors were more common in patients with diabetes (log odds, 1.74 ± 0.72; P = .02).

CONCLUSION

Patients with diabetes had worse histopathologic CRC features. Hyperinsulinemia, insulinlike growth factor receptor activation, and hyperglycemia in diabetes can activate mitogenic pathways stimulating proliferation, invasion, angiogenesis, and metastasis. Future research is needed to identify responsible pathways for targeted therapy and to examine the role of better glycemic control and treatment in patients with CRC and diabetes.