442 Technological Assistance of Cap-Assisted Chromoendoscopy Enhances the Detection Rates of Both Colorectal Adenoma and Proximal Serrated Polyp in an Average-Risk Screening Population: Preliminary Results of a Multi-Center Randomized Controlled Trial

Abstract

Technological Assistance of Cap-Assisted Chromoendoscopy Enhances the Detection Rates of Both Colorectal Adenoma and Proximal Serrated Polyp in an Average-Risk Screening Population: Preliminary Results of a Multi-Center Randomized Controlled Trial Hyun-Soo Kim*, Hong Jun Park, Chan Sik Won, Hyo Keun Jeon, Dongil Park, Jae Myung Cha, Seun-Ja Park, Hwang Choi, Jeong Eun Shin, Chang Soo Eun, Jin-Oh Kim, Hyun Gun Kim, Seong-Eun Kim, Cheol Hee Park, Tae Il Kim, Sung Noh Hong, Dong-Hoon Yang, Byung Chang Kim, Byungho Nam Yonsei Univ. Wonju College of Medicine, Wonju, Republic of Korea; Sungkyunkwan University College of Medicine, Seoul, Republic of Korea; KyungHee University College of Medicine, Hanam, Republic of Korea; Kosin University College of Medicine, Busan, Republic of Korea; The Catholic University of Korea College of Medicine, Incheon, Republic of Korea; Dankook University College of Medicine, Cheonan, Republic of Korea; Hanyang University College of Medicine, Guri, Republic of Korea; Soonchunhyang University College of Medicine, Seoul, Republic of Korea; Ewha Womans University School of Medicine, Seoul, Republic of Korea; Hallym University College of Medicine, Anyang, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; Konkuk University School of Medicine, Seoul, Republic of Korea; University of Ulsan College of Medicine, Seoul, Republic of Korea; National Cancer Center, Goyang, Republic of Korea Background/Aim: There is growing evidence that a transparent cap or chromoendoscopy improve detection of colorectal polyps. However, the combined method of these two technologies has not been proven for colorectal polyp or adenoma detection rate. In this multicenter prospective randomized trial, we examined whether cap-assisted chromoendoscopy (CAP-ACE) enhances colorectal adenoma detection rate especially in the proximal colon. Methods: From March 2010 to October 2011, 1,202 asymptomatic average-risk subjects who underwent the first screening colonoscopy in an age of 45 to 75 were enrolled at 14 hospitals. Eighteen expert colonoscopists (more than 5,000 procedures) have performed procedures. Subjects were randomly allocated to CAP-ACE group and regular colonoscopy (RC) group. We prospectively compared insertion and withdrawal time, polyp detection rate (PDR), adenoma detection rate (ADR), and proximal serrated polyp detection rate (PSPDR) between the two groups. Results: A total of 1,202 subjects were enrolled; 598 CAP-ACEs and 604 RCs were performed. Overall PDR and ADR were 60.3% and 47.6%. A total of 52 advanced lesions were found including 16 tubulovillous adenomas, 2 villous adenomas, 13 high grade dysplasias, 11 intramucosal cancers and 10 invasive cancers. The time to cecal intubation (4.8 vs. 4.8 min, p 0.902) was not different between the groups but withdrawal time was prolonged in CAP-ACE group for indigocarmine solution spray and suction (10.5 vs. 8.7 min, p 0.001). Compared to RC, CAP-ACE did increase PDR (65.9% vs. 54.8%, p 0.001) and ADR (51.8% vs. 45.5%, p 0.033) significantly. In particular, this technological assistance of CAP-ACE even in experts significantly enhanced the proximal adenoma detection rate (34.8% vs. 28.8%, p 0.030) as well as PSPDR (10.5% vs. 6.1%, p 0.006). However, advanced lesions (CAPACE 26/598 (4.3%) vs. RC 26/604 (4.3%), p 0.99) including cancers were equally found between groups. Conclusion: Technological assistance of CAP-ACE enhances not only PDR but also ADR, especially in the proximal colon. These results suggest that CAP-ACE technology provide a potential solution for overcoming the limited effectiveness of colonoscopy in the proximal colon and should be considered as the preferred, high standard colorectal cancer screening method for the average-risk screening population.