Differences between men and women with respect to colorectal cancer mortality despite screening colonoscopy.

BACKGROUND AND AIMS: Women aged 55 to 59 years have a similar prevalence rate and number needed to screen for colorectal adenomas as men at a 10-year younger age. The aim of this study was to determine sex-specific differences in colorectal cancer mortality and estimate the association with adenomas at screening colonoscopy. METHODS: This retrospective study analyzed 323,139 individuals who underwent colonoscopy within a national colorectal cancer screening program in Austria between January 2007 and December 2020. RESULTS: Median patient age was 60 years (interquartile range, 54-67), and the sex distribution in all age groups was nearly identical. Men had significantly higher odds of having an adenoma or serrated polyp, low-risk polyp, high-risk polyp, or colorectal cancer detected at colonoscopy than women (odds ratio [OR] 1.83; 95% confidence interval [CI], 1.80-1.86; OR, 1.46; 95% CI, 1.44-1.49; OR, 1.74; 95% CI, 1.69-1.80; and OR, 1.87; 95% CI, 1.70-2.05, respectively). Strikingly, male sex, when compared with female sex, was associated with an almost 2-fold (hazard ratio, 1.67; 95% CI, 1.05-2.67) increased risk to die from colorectal cancer when an adenoma or serrated polyp was found at the screening colonoscopy and a 4-fold (hazard ratio, 4.14; 95% CI, 2.72-6.3) increased risk when a high-risk polyp was found at the screening colonoscopy. The cumulative incidence for death of colorectal cancer for 60-year-old individuals was 8.5-fold higher in men as compared with women. Markedly, this sex gap narrowed with increasing age, whereas the difference in deaths of other causes remained similar in all age groups. CONCLUSIONS: Our findings strengthen the necessity of sex-specific screening recommendations. Importantly, further prospective studies should focus on sex differences in tumor biology to propose personalized surveillance guidelines.

Detection of high-risk polyps at screening colonoscopy indicates risk for liver and biliary cancer death.

BACKGROUND: Hepatobiliary cancers share risk factors with colorectal cancer (CRC), but there are no combined screening programs for these conditions. AIMS: The aim of this study was to assess whether patients with high-risk colonic polyps are more likely to die from liver related tumors than patients with a negative colonoscopy. METHODS: In this retrospective analysis of mortality data, Austrian screening participants were included. The absolute risk for hepatobiliary cancer death was calculated using the cumulative incidence method. We aimed to identify an association with time to death of hepatobiliary cancer by Cox proportional hazards model. RESULTS: 343,838 colonoscopies performed between 01/2007 and 12/2020 were included in the analysis, of which 17,678 (5.14%) revealed high-risk polyps. Overall hepatobiliary cancer mortality was more than twice as high in patients with high risk polyps (cumulative incidence 0.39%, 95% CI 0.37-0.41%) compared to patients with a negative colonoscopy (cumulative incidence 0.17%, 95% CI 0.17-0.17%). When adjusting for age and sex, having high-risk polyps at screening colonoscopy was significantly associated with hepatobiliary cancer death (HR 1.83, 95% CI 1.29- 2.59, p < 0.001). CONCLUSIONS: Patients with certain colonic polyp characteristics are at increased risk for mortality of liver malignancies. Further studies are needed to determine whether a structured additional screening for liver diseases and consecutive malignancies might be beneficial in these patients.

Polyp characteristics at screening colonoscopy and post-colonoscopy colorectal cancer mortality: a retrospective cohort study.

BACKGROUND AND AIMS: Polyp size and high-grade dysplasia in polyps at screening colonoscopy are considered risk factors for post-colonoscopy colorectal cancer (PCCRC) development and death, which might be averted by surveillance colonoscopy. However, robust evidence backing these risk factors is lacking. We aimed to investigate whether polyp size or dysplasia grade is associated with PCCRC mortality. METHODS: This was a retrospective study including individuals of the Austrian Quality Certificate for Screening Colonoscopy who underwent a colonoscopy between January 2007 and December 2020. We investigated the association of polyp size and dysplasia in polyps with PCCRC mortality according to Cox regression analysis. In addition, whether patients with certain polyp characteristics had similar risk for CRC death compared with the Austrian population was assessed by calculating standardized mortality ratios (SMRs). RESULTS: A total of 316,001 individuals were included. After a median follow-up time of 5.27 years (95% confidence interval [CI], 5.25-5.29), a significant association of polyps 10 to 20 mm (hazard ratio, 4.00; 95% CI, 2.46-6.50; P < .001) as well as high-grade dysplasia (hazard ratio, 6.61; 95% CI, 3.31-13.2; P < .001) with PCCRC death was observed. PCCRC mortality was significantly lower than the expected CRC mortality in the general population in patients with polyps <10 mm and without high-grade dysplasia (SMR, .27; 95% CI, .21-.33; P < .001), which was not observed for patients with polyps ≥10 mm or with high-grade dysplasia (SMR, 2.05; 95% CI, 1.64-2.57; P < .001). CONCLUSIONS: Polyp size ≥10 mm and high-grade dysplasia are associated with PCCRC mortality in screening patients. The data suggest that these patients might benefit most from surveillance colonoscopy.

Comparison of adenoma detection rate and proximal serrated polyp detection rate and their effect on post-colonoscopy colorectal cancer mortality in screening patients.

BACKGROUND: Patients with serrated polyps are at increased risk for post-colonoscopy colorectal cancer (PCCRC); however, evidence for a dedicated serrated polyp detection rate is lacking. The aim of this study was to investigate the association of the proximal serrated polyp detection rate (PSDR) and adenoma detection rate (ADR) with PCCRC death. METHODS: This was a retrospective analysis within the Austrian quality assurance program for screening colonoscopy. Spearman's rank coefficient was calculated for the assessment of association between ADR and PSDR. Whether ADR or PSDR were associated with colorectal cancer mortality was assessed by Cox proportional hazards model. RESULTS: 229/729 screening colonoscopies performed by 308 endoscopists were analyzed. The ADR (hazard ratio [HR] per 1 percentage point increase 0.98, 95 %CI 0.96-0.99) as well as the PSDR (HR per 1 percentage point increase 0.97, 95 %CI 0.94-0.99) were significantly associated with PCCRC death. The correlation coefficient of the ADR and PSDR calculated at every colonoscopy was 0.70 (95 %CI 0.70-0.71), and the corresponding PSDR value for an ADR performance standard of 25 % was 11.1 %. At the end of the study period, 86 endoscopists (27.9 %) reached an ADR of > 25 % and a PSDR of > 11.1 %. CONCLUSIONS: The ADR as well as the PSDR were associated with PCCRC death. Striving for a high PSDR in addition to a high ADR might reduce the risk for PCCRC mortality in patients undergoing screening colonoscopy.

Impact of restrictions due to COVID-19 on a quality-assured screening colonoscopy program.

Background and study aims On February 25, 2020, the first patient was diagnosed with COVID-19 in Austria. On March 16, 2020, the Austrian government imposed restrictions and subsequently the Austrian Medical Association recommended minimizing screening examinations in compliance with government restrictions. The aims of this study were to evaluate the impact of this recommendation on the number of colonoscopies performed weekly and detection of non-advanced adenomas, advanced adenomas (AA) and colorectal cancer (CRC) and to calculate how many undetected adenomas could have developed into CRC. Methods We analyzed the number of colonoscopies and pathological findings within a quality assured national colorectal cancer screening program before the COVID-19 pandemic (March 1, t 2019 to September 1, 2019, Period 1) and compared those rates to months during which access to colonoscopy was limited (March 1, 2020 and September 1, 2020, Period 2) with a Wilcoxon-rank-test and a chi-square test. Results A total of 29,199 screening colonoscopies were performed during Period 1 and 24,010 during Period 2. The mean rate of colonoscopies per week during Period 1 was significantly higher than during Period 2 (808,35 [SD = 163,75] versus 594,50 [SD = 282,24], P  = 0.005). A total of 4,498 non-advanced adenomas were detected during Period 1 versus 3,562 during Period 2 ( P  < 0.001). In total 1,317 AAs and 140 CRCs were detected during Period 1 versus 919 AAs and 106 CRCs during Period 2. These rates did not differ significantly ( P  = 0.2 and P  = 0.9). Conclusions During the COVID-19 crisis, the number of colonoscopies performed per week was significantly lower compared to the year before, but there was no difference in the detection of CRCs and AAs.

New risk stratification after colorectal polypectomy reduces burden of surveillance without increasing mortality.

BACKGROUND: The 2020 postpolypectomy surveillance guideline update of European Society for Gastrointestinal Endoscopy defines a more restrictive group of individuals in need for surveillance 3 years after colonoscopy. AIM: The aim of this cohort study was to validate the new guideline recommendation. METHODS: Based on a national quality assurance program, we compared the 2020 risk group definition with the previous 2013 recommendations for their strength of association with (1) colorectal cancer death, and (2) all-cause death. RESULTS: A total of 265,608 screening colonoscopies were included in the study. Mean age was 61.1 years (SD ±9.0), and 50.6% were women. During a mean follow-up of 59.3 months (SD ±35.0), 170 CRC deaths and 7723 deaths of any cause were identified. 62.4% of colonoscopies were negative and 4.9% were assigned to surveillance after 3 years according to the 2020 guidelines versus 10.4% following the 2013 guidelines, which corresponds to a relative reduction in colonoscopies by 47%. The strength of association with CRC mortality was markedly higher with the 2020 surveillance group as compared to the 2013 guidelines (HR 2.56, 95% CI 1.62-4.03 vs. HR 1.73, 95% CI 1.13-2.62), while the magnitude of association with CRC mortality for low risk individuals was lower (HR 1.17, 95% CI 0.83-1.63 vs. 1.25, 95% CI 0.88-1.76). CONCLUSIONS: Adherence to the updated guidelines reduces the burden of surveillance colonoscopies by 47% while preserving the efficacy of surveillance in preventing CRC mortality.

Association of Adenoma Detection Rate and Adenoma Characteristics With Colorectal Cancer Mortality After Screening Colonoscopy.

BACKGROUND & AIMS: The adenoma detection rate (ADR) and characteristics of previously resected adenomas are associated with colorectal cancer (CRC) incidence and mortality. However, the combined effect of both factors on CRC mortality is unknown. PATIENTS AND METHODS: Using data of the Austrian quality assurance program for screening colonoscopy, we evaluated the combined effect of ADR and lesion characteristics on subsequent risk for CRC mortality. We analyzed mortality rates for individuals with low-risk adenomas (1-2 adenomas <10 mm), individuals with high-risk adenomas (advanced adenomas or ≥3 adenomas), and after negative colonoscopy (negative colonoscopy or small hyperplastic polyps) performed by endoscopists with an ADR <25% compared with ≥25%. Cox regression was used to determine the association of combined risk groups with CRC mortality, adjusted for age and sex. RESULTS: We evaluated 259,885 colonoscopies performed by 361 endoscopists. A total of 165 CRC-related deaths occurred during the follow-up period, up to 12.2 years. In all risk groups, CRC mortality was higher when colonoscopy was performed by an endoscopist with an ADR <25%. Compared with negative colonoscopy with an ADR ≥25%, CRC mortality was similar for individuals with low-risk adenomas irrespective of ADR (for ADR ≥25%: adjusted hazard ratio [HR], 1.22; 95% confidence interval [CI], 0.59-2.49; for ADR <25%: adjusted HR, 1.25; 95% CI, 0.64-2.43) and after negative colonoscopy with ADR <25% (adjusted HR, 1.27; 95% CI, 0.81-2.00). Individuals with high-risk adenomas were at significantly higher risk for CRC death if colonoscopy was performed by an endoscopist with an ADR <25% (adjusted HR, 2.25; 95% CI, 1.18-4.31) but not if performed by an endoscopist with an ADR ≥25% (adjusted HR, 1.35; 95% CI, 0.61-3.02). CONCLUSIONS: Our study adds important evidence for mandatory assessment and monitoring of performance quality in screening colonoscopy. High-quality colonoscopy was associated with a lower risk for CRC death, and the impact of ADR was strongest for individuals with high-risk adenomas.

Interval cancer after colonoscopy in the Austrian National Screening Programme: influence of physician and patient factors.

OBJECTIVE: Postscreening colorectal cancer (PSCRC) after screening colonoscopy is associated with endoscopists' performance and characteristics of resected lesions. Prior studies have shown that adenoma detection rate (ADR) is a decisive factor for PSCRC, but correlations with other parameters need further analysis and ADR may change over time. DESIGN: Cohort study including individuals undergoing screening colonoscopy between 1/2008 and 12/2019 performed by physicians participating in a quality assurance programme in Austria. Data were linked with hospitalisation data for the diagnosis of PSCRC (defined as CRC diagnosis >6 months after colonoscopy). ADR was defined dynamically in relation to the time point of subsequent colonoscopies; high-risk groups of patients were those with an adenoma ≥10 mm, or with high-grade dysplasia, or villous or tubulovillous histology, or a serrated lesion ≥10 mm or with dysplasia, or colonoscopies with ≥3 lesions. Main outcome was PSCRC for each risk group (negative colonoscopy, hyperplastic polyps, low-risk and high-risk group of patients) after colonoscopy by endoscopists with an ADR <20% compared with endoscopists with an ADR ≥20%. RESULTS: 352 685 individuals were included in the study (51.0% women, median age 60 years) of which 10.5% were classified as high-risk group. During a median follow-up of 55.4 months, 241 (0.06%) PSCRC were identified; of 387 participating physicians, 19.6% had at least one PSCRC (8.4% two or more). While higher endoscopist ADR decreased PSCRC incidence (HR per 1% increase 0.97, 95% CI 0.95 to 0.98), affiliation to the high-risk group of patients was also associated with higher PSCRC incidence (HR 3.27, 95% CI 2.36 to 4.00). Similar correlations were seen with regards to high-risk, and advanced adenomas. The risk for PSCRC was significantly higher after colonoscopy by an endoscopist with an ADR <20% as compared with an endoscopist with an ADR ≥20% in patients after negative colonoscopy (HR 2.01, 95% CI 1.35 to 3.0, p<0.001) and for the high-risk group of patients (HR 2.51, 95% CI 1.49 to 4.22, p<0.001). CONCLUSION: A dynamic calculation of the ADR takes into account changes over time but confirms the correlation of ADR and interval cancer. Both lesion characteristics and endoscopists ADR may play a similar role for the risk of PSCRC. This should be considered in deciding about appropriate surveillance intervals in the future.

Impact of adenoma detection rate on detection of advanced adenomas and endoscopic adverse events in a study of over 200,000 screening colonoscopies.

BACKGROUND AND AIMS: Adenoma detection rate (ADR) is the best established quality parameter for screening colonoscopy. Guidelines recommend a target ADR >25% because previous studies have shown that patients of endoscopists with higher ADRs have a lower risk of postcolonoscopy interval cancers. However, studies have shown that improvement in ADR mainly results in increased detection of clinically irrelevant nonadvanced adenomas (NAAs). The impact of ADR on the detection of advanced adenomas (AAs) as well as adverse event rates has yet to be determined. METHODS: A total of 218,193 screening colonoscopies performed between 2007 and 2010 by 262 endoscopists within the Austrian quality assurance program were analyzed. We divided endoscopists into quintiles based on ADRs and calculated mean advanced ADRs (AADRs), NAA detection rates (NAADRs), and adverse event rates for each quintile. Spearman rank-order was used to calculate overall correlations between ADRs and AADRs as well as adverse event rates. Endoscopists with an ADR <25% were compared with those with an ADR >25%. RESULTS: Fifty-one percent of patients were women. Mean ADR was 23.03% (95% confidence interval [CI], 21.93-24.13), AADRs 7.72% (95% CI, 7.19-8.25), and NAADRs 15.31% (95% CI, 14.36-16.27). Overall, there was a significant correlation between ADR and AADR (rho = .51; P < .001). When ADR was divided into quintiles, mean AADR increased with increasing ADR. Even in the highest ADR group (ADR, 31.36%-52.27%) there was a further increase in AADR with a mean of 10.75% (95% CI, 9.31-12.19). Importantly, NAADRs increased continuously with improvement in ADRs but never dissociated from a simultaneous improvement in AADRs. However, there was also a significant correlation of ADRs and endoscopic adverse events (rho = .26, P < .001), even if the perforation rate of .028% (95% CI, .004-.052) in the highest ADR group still remained within the accepted limits based on guidelines. CONCLUSIONS: Increasing ADR is associated with improved detection of AAs and therefore is likely to prevent more cases of colorectal cancer. However, higher ADR was also associated with a higher rate of adverse events, although the adverse event rate was low.

Resection rates and safety profile of cold vs. hot snare polypectomy in polyps sized 5-10 mm and 11-20 mm.

BACKGROUND AND AIMS: Hot snare (HS) is widely used for the resection of adenomas >5 mm. The cold snare (CS) has a better safety profile and is more cost-effective. The aims of this study were to evaluate effectiveness and safety of CS polypectomy (CSP) compared to HS polypectomy (HSP) for adenomas sized 5-10 mm and 11-20 mm. METHODS: 4018 colonoscopies performed within "quality certificate for screening colonoscopy" with one polypectomy of an adenoma sized 5-20 mm each were included. Retrieval rates, complete resection rates and complication rates were assessed and compared between CSP and HSP for adenomas sized 5-10 mm and 11-20 mm. Histologic subgroups were additionally assessed. RESULTS: Complete resection rates (5-10 mm: CSP: 89.4% vs. HSP: 87.9%, p = 0.33; 11-20 mm: CSP: 81.8% vs. 80.9%; p = 1), retrieval rates (5-10 mm: CSP: 99.5% vs. HSP: 99.4%, p = 0.76; 11-20 mm: CSP: 100% vs. HSP: 99%, p = 1) and complication rates (5-10 mm: CSP: 0.2% vs. HSP: 0.2%; p = 1; 11-20 mm: CSP: 0% vs. HSP: 1%, p = 1) were equal between CSP and HSP for adenomas sized 5-10 mm as well as 11-20 mm. For serrated adenomas sized 5-10 mm, HSP was superior to CSP (88.7% vs. 77.2%, p < 0.05) regarding the complete resection rate, but not for advanced adenomas (HSP: 89.1% vs. 87.3%, p = 0.69) or adenomas with high-grade dysplasia (HSP: 76.7% vs. 75%, p = 1). CONCLUSION: This study further supports the use of CSP for polyps sized 5-10 mm and additionally suggests also using CSP for polyps sized 11-20 mm. These findings, as well as the best method for resection of serrated polyps should be validated in further studies.

Evaluation of adenomas per colonoscopy and adenomas per positive participant as new quality parameters in screening colonoscopy.

BACKGROUND AND AIMS: The primary aim of this study was to evaluate adenomas per positive participant (APP) and adenomas per colonoscopy (APC) as new quality parameters in screening colonoscopy. Furthermore, we wanted to assess whether these parameters differ depending on the setting or profession. METHODS: Colonoscopy records were obtained from the database of the Austrian certificate of quality for screening colonoscopy. The Spearman correlation was calculated to compare the adenoma detection rate (ADR), APC, APP, and advanced ADR. The parameters were compared between surgeons and internists and between private practices and hospitals by using the t test. RESULTS: A total of 44,142 colonoscopies performed by 202 endoscopists were included. APC showed a strong correlation with ADR (r = 0.94; P < .01), and both showed a similar correlation with the advanced ADR (ADR: r = 0.47; P < 0.01, APC: r = 0.46; P < .01). APP showed weaker correlations compared with all other parameters (ADR: r = 0.36; P < .01; advanced ADR: r = 0.19; P < .01). Private practices did not differ in ADR, APP or APC from hospitals. Among endoscopists with ADRs of ≥25%, 7 (10.3%) had an APP in the lowest quartile, whereas no endoscopists had an APC in the lowest quartile. CONCLUSIONS: APC did not reveal additional information to ADR, and thus there is no need to use it instead of or additionally to ADR. Although the APP identifies endoscopists who find few adenomas per procedure despite acceptable ADRs, this additional information might not be important in regard to sufficient colorectal cancer prevention, because these endoscopists still had high advanced ADRs.