Diverticular disease and the risk of colon cancer - a population-based case-control study

Follow-Up Colonoscopy for Detection of Missed Colorectal Cancer After Diverticulitis

BACKGROUND & AIMS

Colonoscopy often is recommended after an episode of diverticulitis to exclude missed colorectal cancer (CRC). This is a controversial recommendation based on limited evidence. We estimated the prevalence and odds of CRC and advanced colorectal neoplasia on colonoscopy in patients with diverticulitis compared with CRC screening.

METHODS

Using data from the Gastrointestinal Quality Improvement Consortium registry, we performed a cross-sectional study with patients ≥40 years old undergoing outpatient colonoscopy for an indication of diverticulitis follow-up evaluation or CRC screening. The primary outcome was CRC. The secondary outcome was advanced colorectal neoplasia. Odds ratios (ORs) and 95% CIs were calculated.

RESULTS

We identified 4,591,921 outpatient colonoscopies performed for screening and 91,993 colonoscopies for diverticulitis follow-up evaluation. CRC prevalence was 0.33% in colonoscopies for screening and 0.31% in colonoscopies for diverticulitis. Compared with screening, patients with diverticulitis were less likely to have CRC (adjusted OR, 0.84; 95% CI, 0.74-0.94). CRC prevalence decreased to 0.17% in colonoscopies performed for diverticulitis only. Compared with screening, patients with diverticulitis as the only indication were less likely to have CRC (adjusted OR, 0.49; 95% CI, 0.36-0.68). CRC prevalence increased to 1.43% in patients with complicated diverticulitis. Compared with screening, patients with complicated diverticulitis were more likely to have CRC (adjusted OR, 3.57; 95% CI, 1.59-8.01).

CONCLUSIONS

The risk of CRC cancer is low in most patients with diverticulitis. Patients with complicated diverticulitis are the exception. Our results suggest that colonoscopy to detect missed CRC should include diverticulitis patients with a complication and those not current with CRC screening.

Incidental findings on staging rectal MRI: clinical significance and outcomes

BACKGROUND

Incidental findings (IFs) are commonly seen in staging rectal magnetic resonance imaging (MRI) scans. Their prevalence and clinical significance have not been previously documented.

PURPOSE

To assess the prevalence, clinical significance, and outcomes of incidental findings in MRI scans performed for the staging of rectal cancer.

MATERIAL AND METHODS

A retrospective study was performed at a tertiary colorectal imaging institution. Consecutive MRI rectal staging scans with correlative pathology confirmed primary rectal cancer between March 2014 and March 2021 were identified. The respective imaging reports were reviewed for IFs, which were classified as high, moderate, and low, according to their clinical significance. Medical records were reviewed to assess the outcomes of the highly significant IFs.

RESULTS

There were 266 eligible patients (97 women; mean age = 64.2 years) during the study period. A total of 120 (45%) patients did not have any IFs. A total of 238 IFs in 146 (55%) patients were found. There were 21 (9%) IFs of high clinical significance, 122 (51%) of moderate clinical significance, and 95 (40%) of low clinical significance. The prostate and uterus had the most IFs of high clinical significance, two of which were subsequently pathology confirmed as prostate adenocarcinomas.

CONCLUSION

IFs were seen in more than half of the staging MRI scans in rectal cancer but less than 10% of these were of high clinical significance. The results of this study highlight the range of potential IFs and can guide future research assessing the potential impact of these IFs on patients and the healthcare system.

Risk of Cancer in Patients With Diverticular Disease: A Population-Based Cohort Study

BACKGROUND & AIMS

Several studies have investigated the association between diverticular disease (DD) and colorectal cancer. However, whether there is an association between DD and malignancies other than those in the colorectum remains uncertain.

METHODS

For the 1978-2019 period, we conducted a nationwide, population-based cohort study using national Danish health care data. We followed patients with DD for up to 20 years, beginning 1 year after the date of DD diagnosis until the first occurrence of incident cancer, emigration, death, 20 years of follow-up, or December 31, 2019. We calculated cumulative incidence proportions of cancer and standardized incidence ratios (SIRs) comparing cancer incidence among patients with DD with that in the general population.

RESULTS

We identified 200,639 patients with DD, of whom 20,498 were diagnosed with cancer during the 1-20 years after their DD diagnosis. The SIRs were increased for most cancer sites except for those in the colorectum (SIR, 0.75; 95% confidence interval, 0.72-0.78). The highest SIRs were observed for cancers of the lung, bronchi, and trachea (SIR, 1.20; 95% confidence interval, 1.15-1.24) and kidney (SIR, 1.27; 95% confidence interval, 1.16-1.39).

CONCLUSIONS

Our findings show an increased long-term relative risk of cancer following a diagnosis of DD. These findings are likely caused by prevalence of numerous risk factors in patients with DD that confer an increased risk of cancer. The decreased relative risk of colorectal cancer might be explained by an increased likelihood of patients with DD undergoing colonoscopy with polypectomy.

Risk for colorectal cancer after computed tomography verified acute diverticulitis: A retrospective cohort study with long-term follow-up

BACKGROUND AND OBJECTIVE

Colorectal cancer (CRC) can mimic acute diverticulitis and can thus be misdiagnosed. Therefore, colonic evaluation is recommended after an episode of acute diverticulitis. The aim of this study was to analyze the risk of CRC after computed tomography (CT) verified uncomplicated and complicated acute diverticulitis in short-term and, particularly, long-term follow-up to ensure the feasibility of the primary CT imaging in separating patients with uncomplicated and complicated acute diverticulitis.

METHODS

A retrospective cohort study was conducted in patients with CT-verified acute diverticulitis in 2003-2012. Data on CT findings and colonic evaluations were analyzed. The patients were divided into those with uncomplicated and complicated acute diverticulitis. Patient charts were reviewed 9-18 years after the initial acute diverticulitis episode.

RESULTS

The study population consisted of 270 patients. According to CT scans, 170 (63%) patients had uncomplicated acute diverticulitis and 100 (37%) had complicated acute diverticulitis. Further colonic evaluation was made in 146 (54%) patients. In the whole study population, CRC was found in 7 (2.6%) patients, but CRC was associated with acute diverticulitis in only 4 (1.5%) patients. The short-term risk for CRC was 0.6% (1/170) in uncomplicated acute diverticulitis and 3.0% (3/100) in complicated acute diverticulitis. No additional CRC was found in patients with complicated acute diverticulitis during the long-term follow-up and three cases of CRC found after uncomplicated acute diverticulitis had no observable association with previous diverticulitis.

CONCLUSIONS

In short-term follow-up, the risk of underlying CRC is very low in CT-verified uncomplicated acute diverticulitis but increased in complicated acute diverticulitis. Long-term follow-up revealed no additional CRCs associated with previous acute diverticulitis, indicating that the short-term results remain consistent also in the long run. These long-term results confirm that colonoscopy should be reserved for patients with complicated acute diverticulitis or with persisting or alarming symptoms.

Impact of previous diverticulitis on 5-year survival and recurrence rates in patients with colorectal cancer

BACKGROUND

Diverticulitis and colorectal cancer (CRC) share epidemiological characteristics, but their relationship remains unknown. It is unclear if prognosis following CRC differ for patients with previous diverticulitis compared to those with sporadic cases and patients with inflammatory bowel disease or hereditary syndromes.

AIM

The aim was to determine 5-year survival and recurrence after colorectal cancer in patients with previous diverticulitis, inflammatory bowel disease and hereditary colorectal cancer compared to sporadic cases.

METHODS

Patients <75 years of age diagnosed with colorectal cancer at Skåne University Hospital Malmö, Sweden, between January 1st 2012 and December 31st 2017 were identified through the Swedish colorectal cancer registry. Data was retrieved from the Swedish colorectal cancer registry and chart review. Five-year survival and recurrence in colorectal cancer patients with previous diverticulitis were compared to sporadic cases, inflammatory bowel disease associated and hereditary colorectal cancer.

RESULTS

The study cohort comprised 1052 patients, 28 (2.7%) with previous diverticulitis, 26 (2.5%) IBD, 4 (1.3%) hereditary syndromes and 984 (93.5%) sporadic cases. Patients with a history of acute complicated diverticulitis had a significantly lower 5-year survival rate (61.1%) and higher recurrence rate (38.9%) compared to sporadic cases (87.5% and 18.8% respectively).

CONCLUSION

Patients with acute complicated diverticulitis had worse 5-year prognosis compared to sporadic cases. The results emphasize the importance of early detection of colorectal cancer in patients with acute complicated diverticulitis.

The connection between diverticulosis and colonic superficial neoplastic lesions in patients who underwent screening colonoscopy

PURPOSE

If could be a potential pathophysiological connection between colonic diverticula and colonic superficial neoplastic lesions, beyond the shared risk factors, has been a subject of debate in the last years. This study tries to evaluate the association between diverticulosis and colonic neoplastic lesions.

METHODS

This is a cross-sectional study including asymptomatic patients who underwent a screening colonoscopy (patients with a positive fecal occult blood test under the regional program of colorectal cancer (CRC) screening), surveillance after polypectomy resection, or familiarity (first-degree relatives) between 2020 and 2021 to evaluate the association between diverticula and colonic polyps. A multivariate analysis with multiple logistic regression and odds ratio (OR) to study the independent association between adenomas and adenocarcinomas was performed.

RESULTS

One thousand five hundred one patients were included. A statistically significant association between adenomas or CRC alone and colonic diverticula was found (p = 0.045). On a multivariate analysis of demographic (age, gender) and clinical parameters (familiarity for diverticula and adenoma/CRC), only age was significantly associated with the development of colorectal adenomas or cancer (OR 1.05, 95% CI 1.03-1.07, p < 0.0001).

CONCLUSIONS

This study showed a statistically significant association between diverticula and colonic adenomas. However, it is impossible to establish a cause-effect relationship due to the intrinsic characteristics of this study design. A study with a prospective design including both patients with diverticulosis and without colonic diverticula aimed at establishing the incidence of adenoma and CRC could help to answer this relevant clinical question, since a potential association could indicate the need for closer endoscopic surveillance.

Association between diverticular disease and colorectal cancer: a bidirectional mendelian randomization study

BACKGROUND

Diverticular disease has been inconsistently associated with colorectal cancer risk. We conducted a bidirectional Mendelian randomization study to assess this association.

METHODS

Forty-three and seventy single-nucleotide polymorphisms associated with diverticular disease and colorectal cancer at the genome-wide significance level (p < 5 × 10^- 8) were selected as instrumental variables from large-scale genome-wide association studies of European descent, respectively. Summary-level data for colon cancer, rectum cancer, and colorectal cancer were obtained from genome-wide association analyses of the FinnGen consortium and the UK Biobank study. Summary-level data for diverticular disease was derived from a genome-wide association study conducted in the UK Biobank population. The random effect inverse-variance weighted Mendelian randomization approach was used as the primary method and MR-Egger, weighted-median, and MR-PRESSO approaches were conducted as sensitivity analyses.

RESULTS

Genetically determined diverticular disease was associated with a higher risk of colorectal cancer (beta = 0.441, 95%CI: 0.081-0.801, P = 0.016) in the FinnGen population, but the association was not found in the UK Biobank (beta = 0.208, 95%CI: -0.291,0.532, P = 0.207). The positive association remained consistent direction in the three sensitivity analyses. In the stratified analysis in the FinnGen consortium, an association was found to exist between genetically predicted diverticular disease and colon cancer (beta = 0.489, 95%CI: 0.020-0.959, P = 0.041), rather than rectum cancer (beta = 0.328, 95%CI: -0.119-0.775, P = 0.151). Besides, we found a slight association between colorectal cancer and diverticular disease (beta = 0.007, 95%CI: 0.004-0.010, P < 0.001) when using colorectal cancer as exposome and diverticular disease as outcome. However, there is a large sample overlap in this step of analysis.

CONCLUSION

This Mendelian randomization study suggests that diverticular disease may be a possible risk factor for colorectal cancer and colon cancer rather than rectum cancer in the FinnGen population.

Risk of colorectal advanced neoplasia in patients with acute diverticulitis with and without previous colonoscopy

BACKGROUND AND AIM

Guidelines recommend a colonoscopy after an episode of complicated diverticulitis and after a first episode of uncomplicated diverticulitis. The influence of a previous colonoscopy on postdiverticulitis colonoscopic findings has not been studied. The aim of this work was to examine the incidence of adenoma detection rate (ADR), advanced adenoma (AA) and colorectal cancer (CRC) in patients with diverticulitis with and without previous colonoscopy.

METHOD

This was a retrospective case-control study of subjects with acute diverticulitis. Subsequent and previous colonoscopies were abstracted for ADR, AA and CRC diagnoses. The incidence of neoplasia was compared between patients with and without previous colonoscopy and also with that of a screening population.

RESULTS

Compared with a healthy control group (n = 975), diverticulitis patients without prior colonoscopy (n = 325) had a significantly higher ADR (26.8% vs. 20.5%, p = 0.019) and invasive CRC rate (0.9% vs. 0%, p = 0.016). Risk factors for advanced neoplasia included age ≥ 70 years and complicated diverticulitis. Among subjects with diverticulitis and previous colonoscopy (n = 124), only one patient developed AA and there were no cancer cases.

CONCLUSIONS

A previous normal colonoscopy within 5 years before diverticulitis probably overshadows other risk factors for findings of advanced neoplasia and should be considered in the decision to repeat a colonoscopy.

Cancer risk in patients with diverticular disease: A nationwide cohort study

BACKGROUND

There are little data on diverticular disease and cancer development other than colorectal cancer.

METHODS

We conducted a population-based, matched cohort study with linkage of nationwide registers to the Epidemiology Strengthened by histoPathology Reports in Sweden histopathology cohort. We included 75 704 patients with a diagnosis of diverticular disease and colorectal histopathology and 313 480 reference individuals from the general population matched on age, sex, calendar year, and county. Cox proportional hazards models estimated multivariable-adjusted hazard ratios (HRs) for associations between diverticular disease and overall cancer and specific cancers.

RESULTS

Over a median follow-up of 6 years, we documented 12 846 incident cancers among patients with diverticular disease and 43 354 incident cancers among reference individuals from the general population. Compared with reference individuals, patients with diverticular disease had statistically significantly increased overall cancer incidence (24.5 vs 18.1 per 1000 person-years), equivalent to 1 extra cancer case in 16 individuals with diverticular disease followed-up for 10 years. After adjusting for covariates, having a diagnosis of diverticular disease was associated with a 33% increased risk of overall cancer (95% confidence interval [CI] = 1.31 to 1.36). The risk increases also persisted compared with siblings as secondary comparators (HR = 1.26, 95% CI = 1.21 to 1.32). Patients with diverticular disease also had an increased risk of specific cancers, including colon cancer (HR = 1.71, 95% CI = 1.60 to 1.82), liver cancer (HR = 1.72, 95% CI = 1.41 to 2.10), pancreatic cancer (HR = 1.62, 95% CI = 1.42 to 1.84), and lung cancer (HR = 1.50, 95% CI = 1.39 to 1.61). The increase in colorectal cancer risk was primarily restricted to the first year of follow-up, and especially early cancer stages.

CONCLUSIONS

Patients with diverticular disease who have colorectal histopathology have an increased risk of overall incident cancer.

Association between diverticular disease and prevalence of colorectal adenomatous polyps or adenocarcinomas

Background/Aim: Although the link between diverticular disease (DD) of the colon and colon polyp is known, the relationship between colon adenocarcinoma is not clear. This study evaluated the association between DD and adenomatous polyp or colon adenocarcinoma. Methods: Patients who underwent colonoscopy for the first time in 2020-2021 were evaluated and included in this retrospective cohort study. Patients with a previous history of cancer diagnosis, colon surgery, DD, and inflammatory bowel disease were excluded from the study. Age, gender, colonoscopy indications, colonoscopy diagnoses, presence of DD, characteristics of polyps (pathology, diameter, number, localization), and presence of adenocarcinoma were recorded. Obtained data were analyzed between DD and non-DD groups. Results: A total of 2633 patients were included in the study. The prevalence of DD was 16.4%. Colon adenocarcinoma was detected in 4.7%. The adenomatous polyp rate was 14.1%. A significantly higher rate of adenomatous polyps was detected in the DD group compared to the non-DD group (19.7% vs. 12.9%; P = 0.001). Higher rates of high-grade dysplasia (3.0 vs. 1.1%; P = 0.002) and colon adenocarcinoma (7.2% vs. 4.2%; P = 0.008) were observed in the DD group also. In logistic regression analyses, it was observed that the presence of concomitant DD increases the risk of adenomatous polyps (OR: 1.469, 95% CI: 1.158–1.865), the risk of adenomatous polyps with positive villous component (OR: 2.378, 95% CI: 1.437–3.934), the risk of adenomatous polyps with high-grade dysplasia (OR: 2.822, 95% CI: 1.426–5.582), and the risk of colon adenocarcinoma (OR: 2.953, 95% CI: 1.445–6.533). Conclusion: DD is associated with precancerous lesions of the colon (adenomatous polyp, villous adenoma, high-grade dysplasia) and colon adenocarcinoma. Further studies are needed to investigate its association with colon carcinogenesis and its role and value in cancer screening.

When to Perform a Colonoscopy in Diverticular Disease and Why: A Personalized Approach

Colonoscopy is a crucial diagnostic tool in managing diverticular disease (DD). Diverticulosis can often be an unexpected diagnosis when colonoscopy is performed in asymptomatic subjects, generally for colorectal cancer screening, or it could reveal an endoscopic picture compatible with DD, including acute diverticulitis, in patients suffering from abdominal pain or rectal bleeding. However, alongside its role in the differential diagnosis of colonic diseases, particularly with colon cancer after an episode of acute diverticulitis or segmental colitis associated with diverticulosis, the most promising use of colonoscopy in patients with DD is represented by its prognostic role when the DICA (Diverticular Inflammation and Complication Assessment) classification is applied. Finally, colonoscopy plays a crucial role in managing diverticular bleeding, and it could sometimes be used to resolve other complications, particularly as a bridge to surgery. This article aims to summarize “when” to safely perform a colonoscopy in the different DD settings and “why”.

Time Trend and Association of Early-Onset Colorectal Cancer with Diverticular Disease in the United States: 2010-2021

Purpose: To examine time trends of incidence rates of EOCRC from 2010 to 2021 among patients with and without diverticular disease and to examine whether diverticular disease is associated with increased risk of EOCRC. Methods: This is a retrospective cohort study of 46,179,351 young adults aged 20−49, including 298,117 with diverticular disease. We examined yearly incidence rate of first diagnosis of EOCRC from 2010 through 2021 among patients with and without diverticular disease. The 5-year risk of EOCRC among patients with pre-existing diverticular disease was compared to propensity-matched patients without diverticular disease and EOCRC and odds ratio (OR) and 95% confidence interval (CI) were calculated. Results: The yearly incidence rate of new diagnosis of EOCRC (measured as new cases per 100,000 people per year) in young adults with pre-existing diverticular disease increased from 100 in 2010 to 402 in 2021, 4−6 times higher than in those without diverticular disease (24 in 2010 to 77 in 2021) (p < 0.001). Patients with diverticular disease were at higher risk for EOCRC than those without (OR: 1.76, 95% CI: 1.40−2.32). Conclusion: The incidence of EOCRC continuously increased from 2010 through 2021 in patients with and without diverticular disease and was 4−6 times higher among patients with diverticular disease. Patients with pre-existing diverticular disease were at a significantly increased risk for EOCRC.

Diverticulitis does not increase the long-term risk of developing colon cancer: a systematic review and meta-analysis

PURPOSE

The aim of this review was to examine if diverticulitis increases the long-term risk (> 6 months) of developing colon cancer.

METHODS

A systematic search was conducted in PubMed, Embase, and Cochrane CENTRAL. Google Scholar was also searched. We included studies with human adults of 18 years of age and above. Studies that included only patients with diverticulitis as well as studies comparing groups with and without diverticulitis were included. The primary outcome was the incidence of colon cancer 6 months or more after an episode of diverticulitis.

RESULTS

Twelve records were included with 38,621 patients with diverticulitis. The crude rate of colon cancer among the prospectively followed populations with diverticulitis was by meta-analysis found to be 0.6% (95% CI 0.5-0.6%). The limitations of this review include heterogeneous reporting of outcomes across studies, specifically regarding population and outcome as well as variations in the design and reporting of the studies.

CONCLUSION

We found that the long-term risk of colon cancer after diverticulitis is not increased. The results of our review support current practice on follow-up after an episode of diverticulitis with short-term follow-up being the primary focus.

Post-Diverticulitis Colonoscopy Was Not Associated with Higher Colonic Adenoma and Carcinoma: A Multicenter Case-Control Study

Background and Objectives: Colonoscopy following an episode of acute diverticulitis is currently recommended to rule out underlying colon cancer. However, a number of studies have debated this recommendation. We aimed to explore whether patients with colonic diverticulosis who experienced an episode of acute diverticulitis had higher prevalence colonic pathologies, essentially colonic adenomas and colorectal carcinoma (CRC) on a follow-up colonoscopy. Materials and Methods: We performed a multicenter retrospective study that included patients with a diagnosis diverticulosis as the control group and allocated patients after diverticulitis according to computed tomography (CT) scan and clinical presentation that had performed colonoscopy within 6 months from the acute diverticulitis episode. We compared the detection rate of colonic pathologic findings in both groups. Results: Overall, 367 patients were included. Of them, 134 patients experienced an episode of diverticulitis vs. 233 patients who did not have diverticulitis. On univariate analysis, there was no difference between all pathological findings (CRC, colonic adenomas; OR (odds ratio) 1.51, p = 0.085), and even for each pathological findings alone, there was no difference (for colonic adenomas, p = 0.07; for CRC, p = 0.87). Further sub-analysis revealed that only male gender (OR 4.03, p = 0.004) and smoking (OR 8.67, p < 0.0001) correlated with colonic adenomas and CRC, while moderate to severe disease was not correlated with colonic pathological findings (OR 0.86, 95% CI (confidence interval) 0.4–1.82, p = 0.68). Conclusions: Post-diverticulitis screening colonoscopy has not found a higher rate of colonic pathological findings, especially colonic neoplasia. Decision to perform colonoscopy after acute diverticulitis should be individualized based on risk stratification of colonic neoplasia.

Colorectal Cancer Epidemiology: Recent Trends and Impact on Outcomes

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer related deaths in the world with an estimated number of 1.8 million new cases and about 881,000 deaths worldwide in 2018. The epidemiology of CRC varies significantly between different regions in the world as well as between different age, gender and racial groups. Multiple factors are involved in this variation, including risk factor exposure, demographic variations in addition to genetic susceptibility and genetic mutations and their effect on the prognosis and treatment response. In this mini-review, we discuss the recent epidemiological trend including the incidence and mortality of colorectal cancer worldwide and the factors affecting these trends.

Management of colonic diverticulitis

Left sided colonic diverticulitis is a common and costly gastrointestinal disease in Western countries, characterized by acute onset of often severe abdominal pain. Imaging is necessary to make an initial diagnosis and determine disease severity. Colonoscopy should be done six to eight weeks after diagnosis to rule out a missed colon malignancy. Antibiotic treatment is used selectively in immunocompetent patients with mild acute uncomplicated diverticulitis. The clinical course of diverticulitis commonly includes unpredictable recurrences and chronic gastrointestinal symptoms, which are a detriment to quality of life. A better understanding of prognosis has prompted a shift toward non-operative approaches. The decision to undergo prophylactic colon resection should be individualized to consider the severity of diverticulitis, the patient's health and immune status, and the patient's preferences and values, as well as benefits and risks. Because only a section of colon is removed, recurrent diverticulitis remains a risk. Acute diverticulitis with an abscess is treated with antibiotics that cover Gram negative and anaerobic bacteria, with or without percutaneous drainage. Acute diverticulitis with purulent or feculent contamination of the peritoneal cavity is managed with surgery; primary resection and anastomosis is the procedure of choice in stable patients.

Comparison of colonoscopy after colonic diverticulitis and positive fecal immunochemical tests for the detection of colorectal neoplasia

Background and study aims  The relationship between acute colonic diverticulitis and colorectal cancer (CRC) is unclear, but colonoscopy is recommended to exclude malignancy. We compared the detection rates for colorectal neoplasia in patients with colonic diverticulitis and asymptomatic patients who had positive fecal immunochemical tests (FITs). Patients and methods  In total, 282 patients with acute colonic diverticulitis were hospitalized in our hospital from February 2011 to December 2019. Of them, 143 patients with diverticulitis and 1819 with positive FITs patients during the same period underwent colonoscopy without a prior colonoscopy within 5 years. We retrospectively compared these patients in terms of the invasive CRC rate, advanced neoplasia detection rate (ANDR), adenoma detection rate (ADR), and polyp detection rate (PDR). Results  Compared to the diverticulitis group, the FIT-positive group had a significantly higher CRC rate (0 vs 2.7 %, P  = 0.0061), ANDR (5.6 vs. 14.0 %, P  = 0.0017), ADR (19.6 vs. 53.2 %, P  < .0001), and PDR (44.1 vs. 91.0 %, P  < .0001). Using 1:1 propensity score matching based on age and sex, we obtained 276 matched patients in both groups. After matching, no difference was found in the CRC rate (0 vs 0.7 %) or ANDR (5.8 vs 7.3 %) between groups, but the ADR and PDR were significantly higher in the FIT-positive group (20.3 vs 43.5 %, P  < .0001; 45.7 % vs 86.2 %, P  < .0001). Conclusion  Patients with acute diverticulitis had lower ADRs and PDRs than patients with positive FITs.

Relationship between colonic diverticulosis and colon neoplasms in Japanese patients

BACKGROUND AND AIM

Colonic diverticulosis (CD) has been reported to be associated with presence of colon neoplasms (CNs) in Western patients, since most of the associated risk factors are common between them. However, such correlation has not been fully investigated in Asian patients. In this study, the association of CNs with CD was evaluated in a multicenter investigation.

METHODS

We enrolled 5633 patients who underwent both colonoscopy and esophagogastroduodenoscopy due to annual follow-up, screening for positive occult blood testing and abdominal symptoms between January 2016 and December 2017 at three institutions. The relationship between the presence of CNs and CD was investigated, and predictors for presence of CNs were determined by multivariate logistic analysis.

RESULTS

The enrolled patients consisted of 1799 (31.9%) with CD (average age 70.0 years, male 64.0%) and 3834 without CD (66.0 years, male 52.9%), with the prevalence of CNs in those groups 46.6% and 44.2%, respectively (P = 0.090). Predictors for early colon cancer were shown to be age (OR 1.02, 95% CI 1.01-1.04, P = 0.010), laxatives use (OR 1.76, 95% CI 1.17-2.64, P = 0.007), gastric neoplasms (OR 2.16, 95% CI 1.23-3.81, P = 0.008), and CD (OR 1.64, 95% CI 1.16-2.31, P = 0.005). Early colon cancer in the distal colon was most frequently detected in patients with right-sided CD (RR 2.50, P = 0.001).

CONCLUSION

In Japanese patients, early colon cancer was more frequently found in those with as compared to those without CD. The presence of CD may be an important indicator for an index colonoscopy examination to detect colon cancer. (Clinical-trial-registry: UMIN000038985).

Acute complicated diverticulitis is associated with an increased advanced neoplasia diagnosis rate: A retrospective study on 1852 patients

Recent reports have documented an unchanged rate of occurrence of colorectal cancer (CRC) and have publicised doubts regarding the benefit of prompt colonoscopy procedures after an episode of acute diverticulitis (AD). These reports mandate further evaluation of colonoscopy yield and timing in this regard. The current study aims to determine whether the rate of advanced colonic neoplasia after AD differs from that of average-risk patients, and to identify risk factors that are associated with their development.In this retrospective study, we included all patients who had been hospitalized to the surgery ward in the years 2008 to 2016 with radiographically confirmed AD, and had completed colonoscopies within one year of index hospitalization. Patients who were referred for screening colonoscopies during the same years were included as a control group. We compared the rates of diagnosis of CRC and advanced polyps for both groups before and after adjustment for multiple confounders. Moreover, we investigated risk factors that were associated with increased rate of advanced neoplasia diagnosis.A total of 350 patients were included in the AD group and 1502 patients in the screening colonoscopy control group. The CRC diagnosis rates (1.7% vs 0.3%; P = .09) and overall diagnosis rates of advanced neoplasia (12.3% vs 9.6%; P = .19) were not significantly different when findings were compared between the AD and control groups, respectively. Cases of complicated diverticulitis, however, were associated with increased risk of advanced neoplasia diagnosis (odds ratio (OR) 3.729, 95% confidence interval (CI) 1.803-7.713; P = .01).The diagnosis rate for advanced neoplasia after AD was not significantly different from that of average-risk populations. A course of complicated AD, however, was a potential risk factor.

Association of Colonic Diverticula with Colorectal Adenomas and Cancer

Background and Objectives: Conflicting evidence is reported regarding any association between colonic diverticula with colorectal adenomas or cancer. The present study aimed to evaluate, in a cohort of Caucasian patients, the association between colonic diverticula and colorectal polyps and cancer. Materials and Methods: All consecutive patients undergoing colonoscopy at our institution were included in the study. The presence and location of diverticula, polyps, and cancers were recorded. Histologically, polyps were classified as adenoma (with low or high dysplasia), hyperplastic, or inflammatory. The relative risk of the association of polyps and cancer with diverticula was assessed. Multiple logistic regression analyses, including age, sex, family history for colorectal cancer (CRC), and family history for diverticula, were carried out. Results: During the study period, 1490 patients were enrolled; 37.2% (n = 555) showed colonic diverticula or polyps or CRC (308 males, mean age 66 years). Particularly, 12.3% (n = 183) patients presented only diverticula, 13.7% (n = 204) only polyps or cancer, 11.3% (n = 168) both diseases, and 62.7% (n = 935) neither diverticula nor polyps and cancer. A total of 38 patients presented colorectal cancer, 17 of which had also diverticula. A significant increase in relative risk (RR 2.81, 95% CI 2.27-3.47, p < 0.0001) of colorectal adenoma and cancer in patients with colonic diverticula was found. At multivariate analysis, only diverticula resulted to be significantly associated with colorectal adenomas and cancer (Odds Ratio, OR 3.86, 95% CI 2.90-5.14, p < 0.0001). Conclusions: A significant association of colonic diverticula with colorectal adenoma or cancer was found. This implies that patients with colonic diverticula require a vigilant follow-up procedure for the prevention of colorectal cancer from those applicable to the general population.

CT colonography evaluation of the relationship between colon anatomy and diverticula

OBJECTIVES

In this study, we aimed at investigating the relationship between diverticula and in vivo colonic features such as total colon length (TCL), using CTC. We also evaluated polyps, neoplastic lesions and the correlation among them.

METHODS

This retrospective study considered a series of patients who underwent CTC in our Hospital from 2010 to 2018. We evaluated TCL, the length of each colon segments and sigmoid colon diameter using dedicated software. We verified the presence of diverticula, polyps and neoplasm and measured the number of diverticula using a five-point class scale, evaluating the colonic segments involved by the disease and the number of diverticula for each segment. A logistic regression model was used to analyse the relationship between diverticula and the patients' age, sigmoid colonic diameter and the length of each colonic segments.

RESULTS

The population finally included 467 patients, 177 males and 290 females (average age of 67 ± 12; range 45-96). The mean TCL was 169 ± 25 cm (range 115-241 cm). Out of the 467, 323 patients (69%) had at least one analyse. The patients with diverticula had a mean TCL significantly shorter than patients without diverticula (164 ± 22 vs 181 ± 27 cm; p = 0.001). Among the different variables, sigmoid colon length, sigmoid colon diameter and patient's age were correlated with diverticula (p < 0.01). Otherwise there is no association among diverticula, polyps and neoplasm.

CONCLUSIONS

The presence of colonic diverticula was significantly inversely correlated with TCL.The TCL was not significantly correlated with polyps and cancers.

ADVANCES IN KNOWLEDGE

The presence of colonic diverticula was significantly inversely correlated with total colon length, and in particular they significantly decreased with increasing colon length; our observation could contribute to the comprehension of diverticula pathogenesis.

Underlying Colorectal Cancer Was Rarely Detected After an Episode of Acute Diverticulitis: a Retrospective Analysis of 225 Patients

PURPOSE

The aim of the present study was to determine the prevalence of underlying colorectal carcinoma (CRC) in a cohort of patients who experienced an episode of acute diverticulitis and to assess clinical and laboratory parameters that suggest CRC diagnosis.

METHODS

We performed a single center retrospective study in EMMS Nazareth Hospital from April 2014 to April 2018. All Patients who experienced an episode of acute diverticulitis and underwent a colonoscopy up to 6-month period were included in the study.

RESULTS

Two hundred twenty-five patients (225) patients were included. The mean age was 55.73 ± 13.81 (24-93). One hundred thirty-nine (139) patients were males. Underlying CRC was diagnosed in 2 out of 225 (0.89%) patients and colonic polyps were found in 17 out of 225 patients (7.56%). The average time interval between the episode of diverticulitis and the performance of colonoscopy was 6 weeks. Male gender was significantly associated with CRC and polyp findings (P = 0.039). Moreover, platelet count (353,000 vs. 234,000, P = 0.002) and platelet to lymphocyte ratio (223.65 vs. 127.4, P = 0.015) showed statistically significant correlation with CRC as compared to colonic polyps.

CONCLUSION

The rate of underlying CRC diagnosis was extremely low after an episode of acute diverticulitis. Male gender and platelet to lymphocyte ratio were predictors for the presence of underlying CRC.

Computed tomography diagnosed first time diverticulitis and colorectal cancer

BACKGROUND

Computed tomography (CT) with intravenous contrast is the gold standard for diagnosing diverticulitis. Published results concerning follow-up colonoscopy after an episode of acute diverticulitis to rule out cancer are conflicting. This study aimed to evaluate the risk of underlying colonic malignancy in patients diagnosed with a first time diverticulitis with a state of the art CT investigation with intravenous contrast.

METHODS

Retrospective analysis of all patients with a first episode of diverticulitis diagnosed with CT at Danderyds Hospital, Stockholm, between January 1, 2015, and November 16, 2016. Data on modified Hinchey classification, age, sex, laboratory parameters, body mass index, and colonoscopy findings were recorded.

RESULTS

The study identified 518 patients with a CT-verified first time diverticulitis. Four hundred twenty-six (82%) of the 518 patients underwent follow-up colonoscopy and constitute our study cohort. CT showed that 402 patients had uncomplicated diverticulitis (modified Hinchey Ia), and 24 patients had complicated diverticulitis (modified Hinchey ≥Ib). Colonoscopy showed cancers in 2 (0.5%) of the 426 patients initially diagnosed as acute diverticulitis. In addition, 13 (3%) patients had advanced adenomas, and 121 (28%) patients had benign adenomas upon follow-up colonoscopy. Patients with CT-verified complicated diverticulitis (modified Hinchey ≥Ib) had a significantly higher risk for colon cancer compared with patients with an uncomplicated first time diverticulitis.

CONCLUSION

Our study supports routine follow-up colonoscopy after a first episode of CT-diagnosed complicated diverticulitis. In contrast, we do not find an increased risk for neoplasia in patients with uncomplicated diverticulitis.

Risk of colorectal cancer following CT-verified acute diverticulitis: a nationwide population-based cohort study

AIM

Routine colonoscopy to exclude colorectal cancer (CRC) after CT-verified acute diverticulitis is controversial. This study aimed to compare the incidence of CRC in patients with acute diverticulitis with that in the general population.

METHOD

Patients with an emergency admission for diverticular disease to any Norwegian hospital between 1 January 2008 and 31 December 2010 were included through identification in the Norwegian Patient Registry using International Classification of Diseases (ICD-10) codes K57.1-9. To estimate the age-specific distribution of CT-verified acute uncomplicated diverticulitis (AUD) and acute complicated diverticulitis (ACD) in this nationwide study population, numbers from the largest Norwegian emergency hospital were used. Patients diagnosed with CRC within 1 year following their admission for acute diverticulitis were detected through cross-matching with the Cancer Registry of Norway. Based on both Norwegian age-specific incidence of CRC and estimated age-specific distribution of CT-verified diverticulitis, standard morbidity ratios (SMRs) were calculated.

RESULTS

A total of 7473 patients with emergency admissions for diverticular disease were identified (estimated CT-verified AUD n = 3523, ACD n = 1206); of these 155 patients were diagnosed with CRC within 1 year. Eighty had a CT-verified diverticulitis at index admission [41 AUD (51.3%); 39 ACD (49.7%)]. Compared with the general population, the SMR was 6.6 following CT-verified AUD and 16.3 following ACD, respectively.

CONCLUSION

In the first year after CT-verified acute diverticulitis, especially after ACD, the risk of CRC is higher than in the general population. This probably represents misdiagnosis of CRC as acute diverticulitis. Follow-up colonoscopy should be recommended to all patients admitted with acute diverticulitis.

Meta-analysis of the role of colonoscopy after an episode of left-sided acute diverticulitis

Background

Routine colonoscopy was traditionally recommended after acute diverticulitis to exclude coexistent malignancy. Improved CT imaging may make routine colonoscopy less required over time but most guidelines still recommend it. The aim of this review was to assess the role of colonoscopy in patients with CT‐proven acute diverticulitis.

Methods

PubMed and Embase were searched for studies reporting the prevalence of advanced colorectal neoplasia (ACN) or colorectal carcinoma in patients who underwent colonoscopy within 1 year after CT‐proven left‐sided acute diverticulitis. The prevalence was pooled using a random‐effects model and, if possible, compared with that among asymptomatic controls.

Results

Seventeen studies with 3296 patients were included. The pooled prevalence of ACN was 6·9 (95 per cent c.i. 5·0 to 9·4) per cent and that of colorectal carcinoma was 2·1 (1·5 to 3·1) per cent. Only two studies reported a comparison with asymptomatic controls, showing comparable risks (risk ratio 1·80, 95 per cent c.i. 0·66 to 4·96). In subgroup analysis of patients with uncomplicated acute diverticulitis, the prevalence of colorectal carcinoma was only 0·5 (0·2 to 1·2) per cent.

Conclusion

Routine colonoscopy may be omitted in patients with uncomplicated diverticulitis if CT imaging is otherwise clear. Patients with complicated disease or ongoing symptoms should undergo colonoscopy.

Colorectal Cancer and Polyps in Diverticulosis Patients: A 10-Year Retrospective Study in 13680 Patients

Introduction

Shared by certain epidemiological and etiological characteristics, diverticulosis and colorectal cancer (CRC) as well as colonic polyps has long been linked. This association was studied in several heterogeneous studies but has reported inconsistent results. Clarifying the association is clinically relevant for endoscopist awareness and potential modification of screening and surveillance intervals for diverticulosis patients.

Methods

In this retrospective single-center study, patients diagnosed with diverticulosis on colonoscopy over a 10-year period were included. Each diverticulosis patient was matched with 1 control by age, gender, setting (inpatient/outpatient), and procedure's indication. CRC and polyp detection rates were recorded and compared between the groups before and after adjustment for bowel preparation quality and exam completion. CRC location was recorded and compared between groups.

Results

A cohort of 13680 patients (6840 patients with diverticulosis and 6840 matched controls) was included. Diverticulosis was located mainly to the sigmoid and left colon (94.4%). The CRC diagnosis rate was lower in the diverticulosis group (2% vs. 4.5%, odds ratio = 0.472, P < 0.001, and 95%CI = 0.382‐0.584). Moreover, location of CRC was unrelated to diverticulosis location, as more CRCs in the diverticulosis group were located proximal to the splenic flexure as compared to the control group (42.5% vs 29.5%, respectively; P = 0.007). Diverticulosis, however, was associated with an increased polyp detection rate compared to controls (30.5% vs. 25.5%; odds ratio = 1.2, P < 0.001, and 95%CI = 1.11‐1.299).

Conclusion

We demonstrated that diverticulosis was not associated with an increased risk for CRC. A possible increased polyp detection rate, however, warrants further evaluation in large prospective studies.

Risk of Colorectal Cancer in Patients With Acute Diverticulitis: A Systematic Review and Meta-analysis of Observational Studies

BACKGROUND & AIMS

We performed a systematic review and meta-analysis to assess the prevalence of colorectal cancer in patients with acute diverticulitis.

METHODS

We searched MEDLINE from inception through November 2nd, 2017 for studies reporting the prevalence of colorectal cancer in patients with diverticulitis, identified based on the protocol CRD42017083272. This systematic review was conducted in accordance to the MOOSE guidelines. Pooled prevalence values were obtained by random effects models and robustness was tested by leave-one out sensitivity analyses. Heterogeneity was assessed using the Q-test and quantified based on I2 value. The critical appraisal of included studies was performed using the Newcastle-Ottawa scale.

RESULTS

Our final analysis included 31 studies, comprising 50,445 patients. The pooled prevalence of colorectal cancer was 1.9% (95% CI, 1.5%-2.3%). Patients with complicated diverticulitis had a significantly higher risk for colorectal cancer (prevalence, 7.9%; 95% CI, 3.9%-15.3%) than patients with uncomplicated diverticulitis (prevalence, 1.3%; 95% CI, 0.1%-2%), corresponding to a pooled prevalence ratio of 6.7 (95% CI, 2.5-18.3). Subgroup analyses did not find significant difference in prevalence when separately pooling studies according to ranking on the Newcastle-Ottawa scale, geographical location or length of follow-up. Meta-regression did not find any association between age and colorectal cancer. Among patients who underwent endoscopy, the pooled prevalence of polyps was 22.7% (95% CI, 19.6%-26.0%), of advanced adenomas was 4.4% (95% CI, 3.4%-5.8%), of adenomas was 14.2% (95% CI, 11.7%-17.1%), and of hyperplastic polyps was 9.2% (95% CI, 7.6%-11.2%).

CONCLUSION

In a meta-analysis of observational studies of patients with acute diverticulitis, we found the pooled prevalence of colorectal cancer to be 1.9%. The risk of colorectal cancer was significantly higher in patients with complicated diverticulitis than in patients with uncomplicated diverticulitis.

The relationship between diverticulosis and colorectal neoplasia: A meta-analysis

Background/Aims

Diverticulosis and colorectal neoplasia share epidemiological trends and risk factors which are common in Western countries and incidences increase with age. However, the data on an association between diverticulosis and colorectal neoplasia are conflicting. Thus, we performed a meta-analysis to evaluate whether diverticulosis is associated with colorectal neoplasia.

Methods

A systematic literature search of PubMed, EMBASE, Cochrane Library, Web of Science, and SCOPUS was conducted to identify studies that investigated the association between diverticulosis and advanced colorectal neoplasia (advanced adenoma, colorectal cancer), adenomas, or polyps. The demographic characteristics of patients, including age, gender, indication for colonoscopy, confounding factors, and outcomes of colorectal neoplasia were assessed.

Results

We identified 29 cross-sectional studies (N = 450,953) that investigated the association between diverticulosis and colorectal neoplasia. The meta-analysis found that diverticulosis was not associated with advanced colorectal neoplasia (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.63–1.50). Although there was a positive correlation between diverticulosis and adenomas (OR 1.47, 95% CI 1.18–1.84) and diverticulosis and polyps (OR 1.95, 95% CI 1.15–3.31), diverticulosis did not increase the risk of adenomas (OR 1.34, 95% CI 0.87–2.06) in patients who underwent screening colonoscopy. Moreover, all the increased risk of colorectal neoplasia in patients with diverticulosis was observed in published studies only, and not in unpublished ones.

Conclusions

This meta-analysis demonstrated that diverticulosis is not associated with an increased risk of advanced colorectal neoplasia. Although diverticulosis was associated with a higher risk of polyps and adenomas, the risk was not increased in screening populations. Moreover, the increased risk of colorectal neoplasia in patients with diverticulosis was observed only in published studies and not in unpublished ones.

Incidence and lifetime risk of hospitalization and surgery for diverticular disease

BACKGROUND

Studies on incidence rates of first-time colonic diverticular disease are few, and population-based estimates of lifetime risk are lacking. In this observational study, the incidence, admission rates and lifetime risks of hospitalization and surgery for diverticular disease were investigated.

METHODS

Considering the entire Swedish population as an open cohort, incidence and admission rates, and lifetime risk estimates (considering death as a competing risk) of hospitalization and surgery for diverticular disease were calculated using data from cross-linked national registers and population statistics from 1987 to 2010.

RESULTS

In total, there were 144 107 hospital admissions for diverticular disease in 95 049 individual patients. Of these, 17 599 were admissions with bowel resection or stoma formation in 16 824 patients. The total number of person-years in the population during the study period was 213 949 897. Age-standardized incidence rates were 47·4 (95 per cent c.i. 47·1 to 47·7) for first-time hospitalization with diverticular disease and 8·4 (8·2 to 8·5) per 100 000 person-years for diverticular disease surgery. The corresponding admission rates (including readmissions) were 70·8 (70·4 to 71·2) and 8·7 (8·6 to 8·9) per 100 000 person-years. Following an increase in 1990-1994, rates stabilized. Based on incidence and mortality rates from 2000 to 2010, the estimated remaining lifetime risk of hospitalization from 30 years of age was 3·1 per cent in men and 5·0 per cent in women. The corresponding risk of surgery was 0·5 per cent in men and 0·8 per cent in women.

CONCLUSION

Diverticular disease is a common reason for hospital admission, particularly in women, but rates are stable and the lifetime risk of surgery is low.

Risk of colorectal cancer in patients with diverticular disease

Colorectal cancer constitutes an important burden on the healthcare system. Screening at-risk populations to reduce colorectal cancer-related morbidity and mortality has become part of good clinical practice. However, recommendations regarding subgroups of patients with diverticular disease are subject to controversy.

Herein, we review the most recent literature regarding the prevalence of colorectal cancer in patients with diverticular disease, diverticulitis and uncomplicated diverticulitis.

The recent literature does not identify diverticular disease as a long-term risk factor for colorectal cancer. However, the risk of colorectal cancer is increased in the short-term period after hospitalization related to diverticular disease. According to a recent systematic review and meta-analysis, the prevalence of colorectal cancer is 1.6% in patients with acute diverticulitis who underwent colonoscopy. The risk of having colorectal cancer after an episode of acute diverticulitis is 44-fold higher than that of an age- and gender-adjusted reference population. Despite lower among patients with uncomplicated episode, the risk of colorectal cancer remains 40-fold higher in that subpopulation than that in the reference population.

To conclude, the recent literature describes an increased risk of colorectal cancer among patients with acute diverticulitis compared to the reference population. Colonoscopy is therefore recommended in patients with diverticulitis to exclude colorectal cancer.

Progress and challenges in the management of diverticular disease: which treatment?

Diverticular disease of the colon (DDC) includes a spectrum of conditions from asymptomatic diverticulosis to symptomatic uncomplicated diverticulosis, segmental colitis associated with diverticulosis, and acute diverticulitis without or with complications that may have serious consequences. Clinical and scientific interest in DDC is increasing because of the rising incidence of all conditions within the DDC spectrum, a better, although still limited understanding of the pathogenic mechanisms involved; the increasing socioeconomic burden; and the new therapeutic options being tested. The goals of treatment in DDC are symptom and inflammation relief and preventing disease progression or recurrence. The basis for preventing disease progression remains a high-fiber diet and physical exercise, although evidence is poor. Other current strategies do not meet expectations or lack a solid mechanistic foundation; these strategies include modulation of gut microbiota or dysbiosis with rifaximin or probiotics, or using mesalazine for low-grade inflammation in uncomplicated symptomatic diverticulosis. Most acute diverticulitis is uncomplicated, and the trend is to avoid hospitalization and unnecessary antibiotic therapy, but patients with comorbidities, sepsis, or immunodeficiency should receive broad spectrum and appropriate antibiotics. Complicated acute diverticulitis may require interventional radiology or surgery, although the best surgical approach (open versus laparoscopic) remains a matter of discussion. Prevention of acute diverticulitis recurrence remains undefined, as do therapeutic strategies. Mesalazine with or without probiotics has failed to prevent diverticulitis recurrence, whereas new studies are needed to validate preliminary positive results with rifaximin. Surgery is another option, but the number of acute events cannot guide this indication. We need to identify risk factors and disease progression or recurrence mechanisms to implement appropriate preventive strategies.

Management of Diverticular Disease in the Setting of Other Colorectal Pathology: Data on Simultaneous Issues in Segmental Colitis, Inflammatory Bowel Disease, Cancer, and Complications

Diverticulosis of the colon is a very common anatomical condition. In the Western world, it affects more than 70% of over 65 years old population and represents the fifth most important gastrointestinal disease in terms of health care costs in Western countries. The diagnosis of diverticular disease and diverticulitis can be challenging. Often, there is overlap with other colonic pathologies, such as segmental colitis, ischemia, inflammatory bowel disease, cancer, or infectious colitis. Management of diverticular disease in these settings might be different.

Identification of a rare LAMB4 variant associated with familial diverticulitis through exome sequencing

Diverticulitis is a chronic disease of the colon in which diverticuli, or outpouching through the colonic wall, become inflamed. Although recent observations suggest that genetic factors may play a significant role in diverticulitis, few genes have yet been implicated in disease pathogenesis and familial cases are uncommon. Here, we report results of whole exome sequencing performed on members from a single multi-generational family with early onset diverticulitis in order to identify a genetic component of the disease. We identified a rare single nucleotide variant in the laminin β 4 gene (LAMB4) that segregated with disease in a dominant pattern and causes a damaging missense substitution (D435N). Targeted sequencing of LAMB4 in 148 non-familial and unrelated sporadic diverticulitis patients identified two additional rare variants in the gene. Immunohistochemistry indicated that LAMB4 localizes to the myenteric plexus of colonic tissue and patients harboring LAMB4 variants exhibited reduced LAMB4 protein levels relative to controls. Laminins are constituents of the extracellular matrix and play a major role in regulating the development and function of the enteric nervous system. Reduced LAMB4 levels may therefore alter innervation and morphology of the enteric nervous system, which may contribute to colonic dysmotility associated with diverticulitis.

High Probability of an Underlying Colorectal Cancer Among Patients Treated for Acute Diverticulitis. A Population-Based Cohort Follow-Up Study

INTRODUCTION

Patients treated conservatively for acute diverticulitis (AD) are recommended colonic assessment to rule out an underlying Colorectal cancer (CRC). This has been questioned in patients with a CT diagnosis of uncomplicated AD. We analyzed the frequency of CRC and compared the characteristics of the CRC patients with controls.

METHOD

A cohort of patients treated conservatively for AD during 2005-2011 was identified through an administrative database. Patients diagnosed with CRC within 1 year after the index admission and four randomly selected controls were identified. The patients' files were reviewed to verify the diagnosis and obtain information about the clinical characteristics and the management. A blinded review was performed of CT examinations. The expected number of CRC was calculated from age, sex, and period-specific incidence data. The characteristics of the CRC patients were compared with the controls in a nested case-control study.

RESULTS

890 patients (298 men and 592 women) were treated conservatively for AD. 12 patients were diagnosed with CRC within 1 year, and ten of them in the sigmoid, giving a Standardized Incidence Ratio of 20.0 (95 % CI 10.2-35.7, p<0.001) for sigmoidal cancer. All CRC patients were aged over 70 years. The cancer was missed in six CT scans at the primary reading and in five at the blinded review.

CONCLUSION

Patients conservatively treated for AD are at high risk for an underlying CRC, especially if older than 70 years, which motivates routine follow-up. A CT diagnosis of uncomplicated AD does not rule out CRC.

An 18-Year Nationwide Cohort Study on The Association Between Diverticulitis and Colon Cancer

OBJECTIVE

To investigate the association between diverticulitis and colon cancer in a large, nationwide cohort study.

BACKGROUND

Diverticulitis is a common disease, especially in the Western world. Previous articles have investigated the association between diverticulitis and colon cancer with inconclusive results.

METHODS

We conducted a population-based cohort study based on longitudinal Danish national registers with data from the period 1995 to 2012. Data were extracted from comprehensive Danish national registers containing information from both public and private hospitals. Patients with diverticulitis were identified from the registers and matched by sex and age (± 1 year) with a ratio of 1:10 to people who did not have a registration of diverticulitis or diverticulosis. Main outcome was the event of colon cancer. Subgroup analyses were performed to investigate the effect of colonoscopies and treatment on the colon cancer rate after diverticulitis.

RESULTS

A total of 445,456 people were included, of whom 40,496 had a diagnosis of diverticulitis. The incidence of colon cancer in the group with diverticulitis (4.3%) and the group without diverticulitis (2.3%) differed significantly (P < 0.001) with an incidence rate ratio of 1.86 (95% confidence interval, CI, 1.77-1.96). When adjusted for possible confounders, the association between diverticulitis and cancer remained significant with an odds ratio (OR) of 2.20 (95% CI 2.08-2.32) (P < 0.001). Those with diverticulitis, who had no colonoscopy, had an increased risk of colon cancer compared with those without both diverticulitis and colonoscopy with an OR of 2.72 (95% CI 2.64-2.94) (P < 0.001).

CONCLUSIONS

We found a strong association between development of diverticulitis and colon cancer. This raises several questions regarding the possible causal association and warrants further studies. Patients with diverticulitis should undergo endoscopic surveillance for colon cancer.

Risk of colorectal adenomas, advanced adenomas and cancer in patients with colonic diverticular disease: Systematic review and meta-analysis

BACKGROUND AND AIM

Diverticular disease and colorectal neoplasia are common digestive disorders worldwide. Both diseases share epidemiological trends and certain risk factors including advancing age, physical inactivity, and Western diet and lifestyle. Studies assessing the association between these diseases reported inconsistent results. Thus, we conducted a systematic review and meta-analysis to determine the association between diverticular disease and colorectal adenomas, advanced adenomas and cancer.

METHODS

A comprehensive search of the databases MEDLINE and EMBASE was done from inception through March 2016. Inclusion criterion was the observational studies' assessment of the association between diverticular disease and colorectal neoplasia in adult participants. Pooled OR and 95% confidence interval (CI) were calculated using a random effect.

RESULTS

Data were extracted from 14 observational studies (11 cross-sectional studies, one case-control study and two cohort studies). Diverticular disease was associated with increased odds of adenomas (OR = 1.67, 95% CI 1.27-2.21, 10 studies), but not associated with advanced adenomas (OR = 1.19, 95% CI 0.88-1.62, I²  = 52%, four studies) or colorectal cancer (OR = 1.36, 95% CI 0.47-3.92, I²  = 98%, seven studies).

CONCLUSIONS

Our meta-analysis demonstrated that diverticular disease was associated with colorectal adenomas. Colonoscopists should be aware of this association and carefully examine the entire large bowel in individuals with diverticulosis.

Diverticular Disease of the Colon: News From Imaging

Different scenarios embrace computed tomography imaging and diverticula, including asymptomatic (diverticulosis) and symptomatic patients (acute diverticulitis, follow-up of acute diverticulitis, chronic diverticulitis). If the role of computed tomography is validated and widely supported by evidence in case of acute diverticulitis, this is not the case of patients in their follow-up for acute diverticulitis or with symptoms related to diverticula, but without acute inflammation. In these settings, computed tomography colonography is gaining consensus as the preferred radiologic test.

Diverticular Disease and Colorectal Cancer: Incidental Diagnosis or Real Association? Final Answer

Associations between diverticular disease of the colon and the colorectal cancer has been studied for >60 years. Observational, cross-sectional, and case-control studies as well as large population-based studies gave conflicting results and association was not fully proven. Obtaining the proof was difficult because both diseases share similar clinical characteristics, both increase with age, and both involve similar dietary factors. Long-term observations are difficult as diagnostic methods changed over time from barium enema 50 to 60 years ago, through endoscopy, up to CT and MR in recent years. Cancer or adenomas may be missed within diverticular segment; diverticula may be underreported in patients with colon cancer diagnosis. Most recent 2 large cohort studies have solved the dilemma. These studies have clearly shown that diverticular disease does not increase the risk of colon cancer after the first year of diagnosis. Within the first year of diagnosis the association is strong, most probably due to difficulties with differential diagnosis and misclassifications and shared symptoms. Findings of these studies have led to the conclusion that colon cancer has to be excluded using modern techniques after the first episode of suspected diverticulitis.

Management of Diverticular Disease in Scandinavia

Throughout the last century, the incidence of diverticular disease of the colon has increased tremendously in industrialized countries; nevertheless, the management of this condition is still controversial. Although several international guidelines for the management of diverticular disease are based on the same evidence, the recommendations differ greatly, emphasizing the lack of high-quality prospective studies. In Scandinavia, official guidelines for the management of diverticular disease exist only in Denmark. However, the treatment policies are quite similar in all Scandinavian countries. Computed tomography is the first choice for imaging of acute diverticulitis and its complications. Furthermore, the use of antibiotics in uncomplicated diverticulitis is nearly abandoned in Scandinavia, whereas several international guidelines still recommend their use. There is a broad consensus that abscesses secondary to acute diverticulitis can safely be managed with percutaneous drainage, which is in line with international recommendations. The surgical management of perforated diverticulitis with peritonitis is still as controversial in Scandinavia as elsewhere. Common surgical options are laparoscopic peritoneal lavage, primary resection with anastomosis, and primary resection with terminal colostomy (Hartmann's procedure). Elective sigmoid resection in patients with diverticular disease seems to be performed less frequently in Scandinavia than in other European countries; the right indications are a current matter of debate. Symptomatic uncomplicated diverticular disease in the absence of diverticulitis has not gained great attention in Scandinavia.

Diverticulosis and Diverticulitis

Diverticular disease is a common condition that is associated with variable presentations. For this review article, we performed a review of articles in PubMed through February 1, 2016, by using the following MeSH terms: colon diverticula, colonic diverticulitis, colonic diverticulosis, colonic diverticulum, colonic diverticula, and diverticula. Diverticula are structural alterations within the colonic wall that classically form "pockets" referred to as diverticula. Diverticula form from herniation of the colonic mucosa and submucosa through defects in the circular muscle layers within the colonic wall. Often this is at the sites of penetrating blood vessels in the colon. Diverticular disease is extremely common, which resulted in 2,682,168 outpatient visits and 283,355 hospitalization discharges for diverticulitis or diverticulosis in 2009. Diverticulosis is one of the most common detected conditions found incidentally on colonoscopy. Risk factors for the development of diverticulitis include obesity, smoking, nonsteroidal anti-inflammatory drugs, corticosteroids, and opiates. In contrast, fiber may be protective, but recent studies have questioned the role of fiber in developing diverticular disease. Most patients with diverticulosis will be asymptomatic, but a subset of patients may develop nonspecific abdominal pain (isolated or recurrent), diverticulitis, or segmental colitis associated with diverticulosis. Classically, the treatment of diverticulitis has included antibiotics for all patients. More recent evidence indicates that in mild to even moderate uncomplicated diverticulitis, antibiotics may not be as necessary as initially believed. In more complicated diverticulitis, intravenous antibiotics and surgery may be necessary. Once a patient has had an attack of diverticulitis, increasing fiber may help prevent future attacks. Other modalities such as 5-aminosalicylate products, antibiotics, and probiotics are still of unclear benefit in preventing future episodes of diverticulitis. Similarly, even when patients develop recurrent episodes of diverticulitis, surgery may not be necessary as a prophylactic treatment.

Association between diverticulosis and colonic neoplastic lesions in individuals with a positive faecal immunochemical test

BACKGROUND

The association between diverticulosis and colonic neoplastic lesions has been suggested, but data in literature are conflicting. This study aimed to investigate such a relationship in patients participating in a colorectal cancer screening program who underwent high-quality colonoscopy.

METHODS

Data from consecutive individuals 50-75 years of age with a positive faecal immunological test were considered. Diverticulosis was categorised as present or absent. The prevalence of neoplastic lesions (adenoma, advanced adenoma, and cancer) between individuals with and those without diverticula was compared. A multivariate analysis was performed.

RESULTS

Overall, data from 970 consecutive individuals were evaluated, and diverticulosis was detected in 354 (36.5%) cases. At least one adenoma was detected in 490 (50.5%) people, at least one advanced adenoma in 264 (27.2%), multiple adenoma in 71 (7.3%), whilst a cancer was diagnosed in 48 (4.9%) cases. At univariate analysis, the adenoma detection rate in patients with diverticula was significantly higher than in controls (55.9% vs 47.4%; p = 0.011). At multivariate analysis, presence of diverticulosis was an independent risk factor for both adenoma detection rate (OR = 1.58; 95% CI = 1.14-2.18; p = 0.006) and advanced adenoma (OR = 1.57; 95% CI = 1.10-2.24; p = 0.013), but not for colorectal cancer.

CONCLUSIONS

In a colorectal screening setting, the adenoma detection rate was significantly higher in individuals with diverticulosis than in controls.

Increased serological cancer-associated biomarker levels at large bowel endoscopy and risk of subsequent primary cancer (†)

BACKGROUND

Frequently, subjects offered colonoscopy due to symptoms of colorectal neoplasia are diagnosed with diverticula. The symptoms may, however, also be related to extra-colonic neoplasia. The present retrospective study evaluated a possible association between increased levels of predefined biomarkers in subjects diagnosed with diverticula and risk of developing a primary malignant disease.

METHODS

During 2004/2005, about 4509 subjects were included in a multicenter study with collection of blood samples before bowel endoscopy. The aim was to evaluate a relation between the protein biomarkers CEA, TIMP-1, CA19-9 and YKL-40 and findings at endoscopy. Diverticula were diagnosed in 1021 subjects. By 31 December 2012, subjects who had developed primary malignancy were identified retrospectively and relation between biomarker levels at endoscopy and risk of developing primary malignancy was calculated. The relation with the four biomarkers was divided into three groups: 0 = none increased; 1 = one increased and 2 = two or more increased.

RESULTS

In the observation period, 148 subjects developed a primary malignant disease. Univariable analyzes of the biomarker levels showed that CEA, TIMP-1 and CA19-9 were significantly associated with development of primary malignancy. A multivariable analysis showed that increased levels were associated with development of malignancy (p < 0.0001). The 1- and 5-year cumulative risks of being diagnosed with a primary malignancy were: group 0: 1.1%/5.5%; group 1: 4.2%/10.1% and group 2: 11.4%/18.8%, respectively.

CONCLUSION

Increased levels of CEA, TIMP-1 and CA19-9 at endoscopy with findings of diverticula were associated with a significantly increased risk of being diagnosed with a subsequent primary malignant disease.

New medical strategies for the management of acute diverticulitis

Acute diverticulitis, defined as acute inflammation of a colonic diverticulum, is a common emergency presentation managed by both surgeons and physicians. There have been advances in the medical treatments offered to patients in recent years. Factors predisposing individuals to the development of acute diverticulitis include obesity, smoking, lack of physical activity and medication use, such as NSAIDs. Although widely used, there is limited evidence on the efficacy of individual antibiotic regimens and antibiotic treatment may not be required in all patients. Mesalazine seems to be the only effective treatment for the primary prevention of acute diverticulitis. Finally, evidence of effective measures for the prevention of recurrence is lacking. Furthermore, high-quality randomized controlled trials are required for medical treatments in patients with acute diverticulitis, if management is to be evidence based.

Advanced rectal cancer in a long-term Hartmann's pouch: a forgotten organ revisited

Hartmann's procedure is widely performed as a first-stage operation in cases of left colon emergencies when a one stage management is judged to be unsafe. Forty per cent of patients with Hartmann's procedure never get their stoma reversed, ending with a permanent stoma. The distal excluded Hartmann's pouch is usually forgotten compared to the proximal functioning colon. A 70-year-old man with Hartmann's procedure carried out previously for complicated diverticular disease presented with bleeding per rectum. Invasive adenocarcinoma was confirmed on histology. Subsequent staging revealed a locally advanced rectal cancer. The tumour progressed despite a course of neoadjuvant chemoradiation. The general condition of the patient deteriorated with development of renal failure. The patient died a few weeks later. By reporting this case, we are revisiting the long forgotten Hartmann's pouch to highlight the potential pathologies in the distal stump and to emphasise that a distal stump should not be forgotten even in asymptomatic patients.

Ethical aspects of registry-based research in the Nordic countries

National health care registries in the Nordic countries share many attributes, but different legal and ethical frameworks represent a challenge to promoting effective joint research. Internationally, there is a lack of knowledge about how ethical matters are considered in Nordic registry-based research, and a lack of knowledge about how Nordic ethics committees operate and what is needed to obtain an approval. In this paper, we review ethical aspects of registry-based research, the legal framework, the role of ethics review boards in the Nordic countries, and the structure of the ethics application. We discuss the role of informed consent in registry-based research and how to safeguard the integrity of study participants, including vulnerable subjects and children. Our review also provides information on the different government agencies that contribute registry-based data, and a list of the major health registries in Denmark, Finland, Iceland, Norway, and Sweden. Both ethical values and conditions for registry-based research are similar in the Nordic countries. While Denmark, Finland, Iceland, Norway, and Sweden have chosen different legal frameworks, these differences can be resolved through mutual recognition of ethical applications and by harmonizing the different systems, likely leading to increased collaboration and enlarged studies.