Low-dose CT for the diagnosis of appendicitis in adolescents and young adults (LOCAT): a pragmatic, multicentre, randomised controlled non-inferiority trial. (November 2017)

• Record Type: Journal Article
• Authors: Kim, Hyuk Jung; Jeon, Byeong Geon; Hong, Chong Kun; Kwon, Kye Won; Han, Seung Bong; Paik, Soya; Jang, Suk Ki; Ha, Young Rock; Kim, Young Sik; Lee, Min Hee; Yi, Boem Ha; Shin, Eung Jin; Lee, Hae Kyung; Kim, Hee Kyung; Kim, Ho Jung; Choi, Jae Hyung; Cho, Young Soon; Kim, Min-Jeong; Kim, Dong Kyu; Choe, Ji-Young; Min, Kyueng-Whan; Lim, Man Sup; Ha, Sang Ook; Lim, Sang Woo; Sohn, Youdong; Lee, Young Hwan; Park, Ji Hoon; Gu, Bon Seung; Lee, Hye Seung; Lee, Jae Hyuk; Sim, Ji Ye; Kim, Joonghee; Lee, Kyoung Ho; Kim, Kyuseok; Ahn, Soyeon; Kang, Sung-Bum; Lee, Yoon Jin; Jo, You Hwan; Kim, Young Hoon; Ko, Yousun; Choi, Seung Joon; Song, Bohyung; Goh, Byung Ho; Lim, Chaesuk; Kim, Chang Rae; Seo, Cho Rong; Kim, Eunbaeck; Han, Gio; Woo, Jae-Hyug; Kim, Jinhyun; Min, Kyoungjin; Lee, Min-A; Jeong, Min Ju; Lee, Min Kyoung; Lim, Yong Su; Shim, Young Sup; Park, Sung Bin; Kim, Chan Woong; Lee, Dong Hoon; Lee, Seung Eun; Kim, Sung Eun; Choi, Yoo Shin; Rha, Sung Eun; Jung, Eun Sun; Na, Gun Hyung; Kim, Han Joon; Yoo, Han Mo; Chang, Hye Kyung; Choi, Joon Il; Park, Kyu Nam; Park, Michael Yong; Choi, Moon Hyung; Oh, Sang Hoon; Jung, Seung Eun; Lee, Sohee; Im, Soo Ah; Kim, Soo Hyun; Oh, Soon Nam; Hong, Tae Ho; Kang, Won-Kyung; Lee, Young Joon; Lee, Young Hwan; Kang, Dong Baek; Han, Hyun Soo; Choi, Jeong Woo; Yoon, Ki-Jung; Hwang, Yong; Hong, Seong Sook; Hwang, Eui Sung; Chung, Heajin; Jang, Hye Young; Hwang, Jiyoung; Park, Jun Bum; Hur, Kyung Yul; Jeen, Yoon Mi; Lee, Young Joo; Cho, Young Shin; Cho, Han Jin; Choi, Inyoung; Park, Jong Hak; Kim, Jooyeong; Yeom, Suk Keu; Moon, Sung Woo; Kim, Young Sik; Kim, Mi Sung; Shin, Dong Hyuk; Kwon, Heon-Ju; Choi, Pil Cho; Han, Sang Kuk; Woo, Ji Young; Kang, Gu Hyun; Kim, Han Myun; Choi, Hyun Young; Yang, Ik; Jang, Jae Ho; Kim, Jeong Won; Yoon, Sang Nam; Kim, Won Hee; Jang, Yong Soo; Park, Mi-Suk; Park, In Cheol; Lee, Jae Gil; Kim, Min Joung; Chung, Yong Eun; Lee, Jongmee; Kim, Baek-Hui; Lee, Chang Hee; Kim, Jung-Youn; Kang, Sanghee; Choi, Sung-Hyuk; Park, Yang Shin; Cho, Seong Whi; Park, Chan Woo; Chae, Gi Bong; Ohk, Taek Guen; Jeon, Yong-Hwan; Hong, Nurhee; Wi, Dae Han; Lee, Jun Hee; Kwon, Jung Nam; Lee, Seok Youn; Han, Weon-Cheol; Song, Young Cheol; Kim, Mi Jeong; Kwon, Jung Hyeok; Beak, Seoung Kyu; Kim, Sung Jin; Choi, Woo Ik; Kang, Yu Na; Shin, Cheong-Il; Lee, Dong Ho; Kang, Gyeong Hoon; Joo, Ijin; Yoon, Jeong Hee; Park, Ji Won; Park, Kyu Joo; Shin, Sang Do; Ryoo, Seung-Bum; Jeong, Seung-Yong; Ahn, Su Joa; Kim, Tae Han; Chang, Won; Kwon, Yoon-Hye; Shin, Sang Soo; Kim, Hee Joon; Kim, Ho Goon; Cho, Yong Soo; Choi, Yoo Duk; Kim, Bong Soo; Hyun, Chang Lim; Choi, Guk Myung; Jeong, In Ho; Kang, Kyeong Won; Kim, Seung Hyoung; Kim, Woo Jeong; Kang, Young Joon; Kim, Kwang Pyo;
• Is Part Of: Lancet gastroenterology and hepatology. Volume 2:Number 11(2017)
• Page Start: 793
• Page End: 804
• Publication Date: 2017-11
• DOI: 10.1016/S2468-1253(17)30247-9
• Languages: English
• ISSNs: 2468-1253

Abstract

Summary: Background: CT radiation is arguably carcinogenic. Results from single-centre studies, mostly retrospective, have advocated lowering the CT radiation dose for the diagnosis of appendicitis. However, adoption of low-dose CT has been slow. We aimed to assess the effectiveness of low-dose CT compared with standard-dose CT in the diagnosis of appendicitis in adolescents and young adults. Methods: We did this pragmatic, multicentre, randomi s ed controlled non-inferiority trial at 20 South Korean teaching hospitals with little experience with low-dose CT. Patients aged 15–44 years with suspected appendicitis were randomly assigned (1:1), via computer-generated random assignments (permuted block sizes of two, four, six, and eight) concealed in sequentially numbered envelopes, to receive low-dose CT (2 mSv) or standard-dose CT (≤8 mSv). Randomisation was stratified by site. Group allocation was concealed from patients, outcome assessors, and adverse event adjudicators; care providers, site pathologists, and data collectors were aware of allocation. The primary endpoint was the negative (unnecessary) appendectomy rate among all appendectomies, with a non-interiority margin of 4·5% for low-dose versus standard-dose CT. Primary analy s is was by modified intention to treat, which included all patients who received an appendectomy in the group to which they were assigned. This trial is registered withClinicalTrials.gov, numberNCT01925014 . Findings: Between Dec 4, 2013, and Aug 18, 2016, we assigned 1535 patients to the low-dose CT group and 1539 patients to the standard-dose CT group. 22 (3·9%) of 559 patients had a negative appendectomy in the low-dose group versus 16 (2·7%) of 601 patients in the standard-dose group (difference 1·3%, 95% CI −0·8 to 3·3; p=0·0022 for the non-inferiority test). We recorded 43 adverse events in 43 (2·8%) of 1535 patients in the low-dose group and 41 adverse events in 40 (2·6%) of 1539 patients in the standard-dose group. One life-threatening adverse event of anaphylaxis caused by an iodinated contrast material occurred in the low-dose group. Interpretation: Radiation dose of appendiceal CT for adolescents and young adults can be reduced to 2 mSv without impairing clinical outcomes. In view of the vast number of appendiceal CT examinations done worldwide, use of low-dose CT could prevent a sizeable number of radiation-associated cancers in the future. Funding: Korea Health Industry Development Institute, Seoul National University Bundang Hospital, Dasol Life Science, and Bracco Imaging Korea.