Detection rates for adenomas, serrated polyps and clinically relevant serrated polyps can be easily estimated by individually calculated detection rate ratios.

Background and aims: Adenoma detection rate (ADR) is a key quality indicator for colonoscopy; however, it is cumbersome to obtain. We investigated if detection rates (DRs) for adenomas, serrated polyps (SPs) and clinically relevant SP (crSPDR) can be accurately estimated by individualized DR ratios (DRRs) in a multicenter primary colonoscopy screening cohort of average-risk individuals.Methods: DRRs were calculated by dividing DRs for a certain polyp entity by polyp detection rate (PDR) for each endoscopist individually on the basis of his/her first 50 (DRR50) and 100 (DRR100) consecutive colonoscopies. DRs were estimated for each endoscopist by multiplying his/her DRR for a certain polyp entity with his/her PDR of subsequent colonoscopies in groups of 50 (DRR50) and 100 (DRR100) consecutive colonoscopies. Estimated and actual DRs were compared.Results: Estimated DRs showed a strong correlation with actual DRs for adenomas (r = 0.86 and 0.87; each p < .001), SPs (r = 0.85 and 0.91; each p < .001) and crSPs (r = 0.82 and 0.86; each p < .001) using DRRs derived from first 50 and 100 consecutive colonoscopies. Corresponding root mean square error (RMSE) between individual estimated and actual DRs using DRR50 and DRR100 was 5.3(±4.6)% and 4.5(±4.8)% for adenomas, 5.2(±4.1)% and 3.9(±2.8)% for SP, 3.1(±3.1)% and 2.8(±2.5)% for crSP, respectively. RMSE was not significantly different between DRR50 and DRR100 for ADR (p = .445), SPDR (p = .178) and crSP (p = .544).Conclusions: DR for all relevant polyp entities can be accurately estimated by using individual DRRs. This approach may enable endoscopists to easily track their performance measures in daily routine.

Detection of clinically relevant serrated polyps during screening colonoscopy: results from seven cooperating centers within the German colorectal screening program.

BACKGROUND: Serrated polyps have been recognized as precursors of colorectal cancer (CRC) via the serrated pathway. Endoscopic detection and histopathological evaluation of serrated polyps are challenging. The aims of this study were to determine detection rates of the recently proposed entity of clinically relevant serrated polyps (crSPs) and to identify factors that influence their detection in a primary colonoscopy screening cohort. METHODS: We retrospectively analyzed average-risk screening colonoscopies performed at a tertiary academic hospital and six community-based private practices in Germany between 01/01/2012 and 14/12/2016. Exclusion criteria were age < 50 years, conditions with increased risk for CRC (e. g. inflammatory bowel disease, history of CRC, hereditary cancer syndromes), and incomplete procedures. CrSPs were defined as serrated polyps ≥ 10 mm and/or > 5 mm located proximally to the splenic flexure. Conventional adenomas were defined as adenomas excluding serrated polyps. RESULTS: A total of 4161 colonoscopies from average-risk individuals were included (median age 62 years [interquartile range 56 - 69]; 48.6 % male). CrSPs were detected in 6.9 %, with a mean detection rate of 4.7 % (95 % confidence interval 2.3 % - 7.2 %). Detection rates ranged from 0 % to 16.2 %. In multivariate analysis, simultaneous detection of conventional adenomas and an endoscopist adenoma detection rate of ≥ 25 % were significantly associated with increased detection of crSPs, with odds ratios of 1.43 (95 %CI 1.11 - 1.85; P = 0.01) and 7.35 (95 %CI 4.43 - 12.19; P < 0.001). The individual endoscopist's detection rate for conventional adenomas and crSPs were significantly correlated (r = 0.54, P = 0.02). CONCLUSION: Detection rates for crSPs differed between participating endoscopists. However, individual skills to detect polypoid lesions have a relevant bearing on the detection rate of crSPs.

The Barrett-associated variants at GDF7 and TBX5 also increase esophageal adenocarcinoma risk.

Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) represent two stages within the esophagitis-metaplasia-dysplasia-adenocarcinoma sequence. Previously genetic risk factors have been identified that confer risk to BE and EAC development. However, to which extent the genetic variants confer risk to different stages of the BE/EAC sequence remains mainly unknown. In this study we analyzed three most recently identified BE variants at the genes GDF7 (rs3072), TBX5 (rs2701108), and ALDH1A2 (rs3784262) separately in BE and EAC samples in order to determine their risk effects during BE/EAC sequence. Our data show that rs3072 at GDF7 and rs2701108 at TBX5 are also associated with EAC and conclude that both loci confer disease risk also at later stages of the BE/EAC sequence. In contrast, rs3784262 at ALDH1A2 was highly significantly associated with BE, but showed no association with EAC. Our data do not provide evidence that the ALDH1A2 locus confers equal risk in early and late stages of BE/EAC sequence.

Supportive evidence for FOXP1, BARX1, and FOXF1 as genetic risk loci for the development of esophageal adenocarcinoma.

The Barrett's and Esophageal Adenocarcinoma Consortium (BEACON) recently performed a genome-wide association study (GWAS) on esophageal adenocarcinoma (EAC) and Barrett's esophagus. They identified genome-wide significant association for variants at three genes, namely CRTC1, FOXP1, and BARX1. Furthermore, they replicated an association at the FOXF1 gene that has been previously found in a GWAS on Barrett's esophagus. We aimed at further replicating the association at these and other loci that showed suggestive association with P < 10(-4) in the BEACON sample. In total, we tested 88 SNPs in an independent sample consisting of 1065 EAC cases and 1019 controls of German descent. We could replicate the association at FOXP1, BARX1, and FOXF1 with nominal significance and thereby confirm that genetic variants at these genes confer EAC risk. In addition, we found association of variants near the genes XRCC2 and GATA6 that were strongly (P < 10(-5) ) although not genome-wide significantly associated with the BEACON GWAS. Therefore, both variants and corresponding genes represent promising candidates for future EAC association studies on independent samples.