Published online Mar 15, 2018. doi: 10.4251/wjgo.v10.i3.82
Peer-review started: December 21, 2017
First decision: January 15, 2018
Revised: February 5, 2018
Accepted: March 6, 2018
Article in press: March 6, 2018
Published online: March 15, 2018
Sessile serrated adenomas (SSAa) are difficult to detect and strongly associated with interval colorectal cancer (CRC). It is necessary to investigate the factors which influence SSA detection and to evaluate the SSA detection rate (SSADR).
In Western countries, some reports have described the correlation of ADR and SSADR. However, to the best of our knowledge, there has been no report in Asian countries showing a correlation between ADR and SSADR. In this context, we investigated the association between ADR and SSADR with significant predictors for SSA detection in total colonoscopy screening or surveillance in the Japanese population.
The main objectives were as follows; the prevalence of each polyp (low-grade or high-grade adenoma, cancer, SSA, or SSA with cytological dysplasia), each gastoroenterologist’s ADR and SSADR, the association between ADR and SSADR for each gastroenterologist and predictors of adenoma and SSA detection.
Total colonoscopies performed by the gastroenterologists at the University of Tokyo Hospital between January and December 2014 were retrospectively identified. The prevalence of each type of polyp was investigated. Predictors of adenoma and SSA detection were examined using logistic generalized estimating equation models. The association between ADR and SSADR for each gastroenterologist was investigated by calculating a correlation coefficient weighted by the number of each gastroenterologist’s examination.
A total of 3691 colonoscopies by 35 gastroenterologists were assessed. 978 low grade adenomas (26.5%), 84 high grade adenomas (2.2%), 81 cancers (2.2%), 66 SSAs (1.8%) and 2 SSAs with cytological dysplasia (0.1%) were detected. Adenoma detection was the only significant predictor of SSA detection (adjusted OR: 2.53, 95%CI: 1.53-4.20; P < 0.001). The correlation coefficient between ADR and SSADR weighted by the number of each gastroenterologist’s examinations was 0.606 (P < 0.001).
Our study suggests that ADR is correlated with SSADR. Some reports have described the correlation of ADR and SSADR in Western countries patients; however, to our knowledge, the prevalence of SSAs or SSADR in Asian populations has not yet been fully investigated and appropriate SSADR has not been determined. Therefore, our study holds importance, as it is the first report to demonstrate the correlation between SSADR and ADR in Asian populations. In addition, patients with adenomas may have a higher prevalence of SSAs than those without adenomas.
This study was a retrospective single center study, and the number of SSA cases was small. Therefore, a large-scale prospective study will be needed to validate these findings.