Screening Colonoscopy from a Large Single Center of Thailand - Something Needs to be Changed?

Aswakul, Pitulak,Prachayakul, Varayu,Lohsiriwat, Varut,Bunyaarunnate, Thirapol,Kachintorn, Udom Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Background: Results of screening colonoscopy from Western countries reported adenoma detection rates (ADRs) of 30-40% while those from Asia had ADR as low as 10%. There have been limited data regarding screening colonoscopy in Thailand. The objectives of this study were therefore to determine polyp and adenoma detection rates in Thai people, to evaluate the incidence of colorectal cancer detected during screening colonoscopy and to determine the endoscopic findings of the polyps which might have some impact on endoscopists to perform polypectomy. Materials & Methods: This study was a retrospective electronic chart review of asymptomatic Thai adults who underwent screening colonoscopy in our endoscopic center from June 2007 to October 2010.Results: A total of 1,594 cases were reviewed. The patients had an average age of $58.3{\pm}10.5$ years (range 27-82) and 55.5% were female. Most of the cases (83.8%) were handled by staff who were endoscopists. A total of 488 patients (30.6%) were reported to have colonic polyps. Left-sided colon was the most common site (45.1%), followed by right-sided colon (36.5%) and the rectum (18%). Those polyps were removed in 97.5% of cases and 88.5 % of the polyps were sent for histopathology (data lost 11.5%). Two hundred and sixty three cases had adenomatous polyps, accounting for 16.5 % ADR. Advanced adenomas were detected in 43 cases (2.6%). Hyperplastic polyps were mainly located distal to the splenic flexure of the colon whereas adenomas were found throughout the large intestine. Ten cases (0.6%) were found to have colorectal cancer. Four advanced adenomas and two malignant polyps were reported in lesions ${\leq}$ 5 mm. Conclusion: The polyp detection rate, adenoma detection rate, advanced adenoma detection rate and colorectal cancer detection rate in the screening colonoscopy of Thai adults were 30.9%, 16.5%, 2.6% and 0.6% respectively. Malignant transformation was detected regardless of the size and location of the polyps. Therefore, new technology would play an important role indistinguishing polyps.

대장내시경검사에서 대장내시경 회수시간과 폴립 발견율과의 관계

안상봉,한동수,조현석,변태준,김태엽,은창수,전용철,손주현,김선민 대한소화기내시경학회 2009 Clinical Endoscopy Vol.38 No.2

목적: 대장내시경 회수시간은 대장내시경검사에서 폴립 발견의 중요한 질관리 지표 중 하나이다. 이번 연구에서는 대장내시경검사에서 시술자간의 폴립 발견율의 차이가 있는지를 알아보고, 이에 영향을 미치는 인자를 찾아보고자 하였다. 대상 및 방법: 한양대학교 구리병원의 전임의 2년차 7명이 시행한 대장내시경 1,515건 중 장 절제술의 기왕력이 있거나, 염증성 장질환 환자 등을 제외한 1,299건을 후향적으로 분석하였다. 대상 환자의 폴립 발견율, 대장내시경 삽입시간, 회수시간, 장 정결도, 폴립 크기, 폴립 위치 등을 조사하였다. 결과: 대장내시경을 시행한 시술자별로 분류하였을 때, 시술자간 폴립 발견율은 15∼35%로 큰 차이가 있었다. 각 군 마다 성별, 나이, 장 정결도, 폴립의 위치에 있어서 의미있는 차이는 없었다. 평균 대장내시경 삽입시간은 7.6∼12.3분으로 개인별로 차이가 있었으나, 대장내시경 삽입시간과 폴립 발견율은 관계가 없었다. 대장내시경 회수시간은 개인마다 평균 3.6±2.8분에서 7.1±2.5분까지로 차이가 있었으며, 대장내시경 회수시간과 폴립 발견율에서 의미있는 상관관계가 있었다(p<0.001). 또한, 대장내시경 회수시간이 긴 경우에 5 mm 이하의 작은 폴립의 발견율이 높았다. 평균 대장내시경 회수시간을 6분을 기준으로 분석하였을 때 회수시간이 6분 이상인 경우 6분 미만에 비해 폴립 발견율이 의미있게 높았다(30.7% vs 18.4%, p< 0.001). 결론: 대장내시경검사에서 시술자간 폴립 발견율의 차이가 있었고, 대장내시경 회수시간과 폴립 발견율에는 양의 상관관계가 있었다. 대장내시경 검사에서 폴립 발견율을 높이기 위해서는 충분한 대장내시경 회수시간이 필요할 것이다. Background/Aims: The colonoscopic withdrawal time has been proposed as a quality indicator for colonoscopy, and this is based on the recent evidence that the Colon withdrawal time is associated with adenoma detection rate. In this study, we examined the difference of the polyp detection rates between practicing endoscopists, and we analysed certain factors that might lead to such differences, and particularly the colonoscopic withdrawal time. Methods: We retrospectively evaluated the colonoscopic procedures that were performed by 7 second-year GI fellows at Hanyang University Guri Hospital. A total of 1,515 colonoscopies were assessed for the polyp detection rate, the insertion time, the withdrawal time, bowel preparation, the size of the detected polyps and the location of polyps. Results: The median withdrawal time for the case with no polyps removed was 3.6 to 7.1 minutes. There was a strong positive correlation between the colonoscopic withdrawal times and the polyp detection rates (p<0.001). Furthermore, a longer withdrawal time resulted in discovering a higher percentage of small polyps. On comparing groups, the group of colonoscopists with a withdrawal time longer than 6 minutes had a higher rate of detecting polyps (30.7% vs 18.4%, p<0.001). Conclusions: There is wide range of polyp detection rates among practicing colonoscopists and there is strong positive correlation between the colonoscopic withdrawal times and the rate of detecting polyps. A long enough withdrawal time, perhaps 7 minutes, is needed to raise the rate of detecting polyps during colonoscopy.

Endoscopy Nurse Participation May Increase the Polyp Detection Rate by Second-Year Fellows during Screening Colonoscopies

( Tae Sun Kim ),( Dong Il Park ),( Do Young Lee ),( Jang Hyuk Yoon ),( Jung Ho Park ),( Hong Joo Kim ),( Yong Kyun Cho ),( Chong Il Sohn ),( Woo Kyu Jeon ),( Byung Ik Kim ),( Jae Wan Lim ) 대한소화기학회 2012 Gut and Liver Vol.6 No.3

Background/Aims: The aim of this study was to assess the effects of endoscopy nurse participation on polyp detection rate (PDR) and adenoma detection rate (ADR) of second-year fellows during screening colonoscopies. Methods: This was a single-center, prospective, randomized study comparing a fellow alone and a fellow plus an endoscopy nurse as an additional observer during afternoon outpatient screening colonoscopies. The primary end points were PDR and ADR. Results: One hundred ninety-one colonoscopies performed by a fellow alone and 192 colonoscopies performed by a fel-low plus an endoscopy nurse were analyzed. The PDR was significantly higher when the nurse was involved (53.1% vs. 41.3%, p<0.05); however, there was no significant differ-ence in the ADR between the two groups (38.5% vs. 29.8%, p=0.073). There was no difference in the percentage of patients with ≥2 polyps, advanced adenomas, polyp size, polyp location, and polyp shapes between the two groups. There was no difference in the PDR according to the level of experience of the endoscopy nurse. Conclusions: Endoscopy nurse participation as an additional observer during screen-ing colonoscopy performed by second-year fellow increases the PDR; however, the level of experience of the nurse was not an important factor. (Gut Liver 2012;6:344-348)

Does Metformin Affect The Incidence of Colonic Polyps and Adenomas in Patients with Type 2 Diabetes Mellitus?

( Youn Hee Cho ),( Bong Min Ko ),( Shin Hee Kim ),( Yu Sik Myung ),( Jong Hyo Choi ),( Jae Pil Han ),( Su Jin Hong ),( Seong Ran Jeon ),( Hyun Gun Kim ),( Jin Oh Kim ),( Moon Sung Lee ) 대한장연구학회 2014 Intestinal Research Vol.12 No.2

Background/Aims: Colorectal cancer (CRC) develops from colonic adenomas. Type 2 diabetes mellitus (DM) is associatedwith a higher risk of CRC and metformin decreases CRC risk. However, it is not certain if metformin affects the developmentof colorectal polyps and adenomas. This study aimed to elucidate if metforminaffects the incidence of colonic polyps and adenomasin patients with type 2 DM. Methods: Of 12,186 patients with type 2 DM, 3,775 underwent colonoscopy between May2001 and March 2013. This study enrolled 3,105 of these patients, and divided them in two groups: 912 patients with metforminuse and 2,193 patients without metformin use. Patient clinical characteristics, polyp and adenoma detection rate in the twogroups were analyzed retrospectively. Results: The Colorectal polyp detection rate was lower in the metformin group than inthe non-meformin group (39.4% vs. 62.4%, P <0.01). Colorectal adenoma detection rate was significantly lower in the metformingroup than in the non-metformin group (15.2% vs. 20.5%, P <0.01). Fewer advanced adenomas were detected in the metformingroup than in the non-metformin group (12.2% vs. 22%, P <0.01). Multivariate analysis identified age, sex, Body mass index andmetformin use as factors associated with polyp incidence, whereas only metforminwas independently associated with decreasedadenoma incidence (Odd ratio=0.738, 95% CI=0.554-0.983, P =0.03). Conclusions: In patients with type 2 DM, metforminreduced the incidence of adenomas that may transform into CRC. Therefore, metformin may be useful for the preventionof CRC in patients with type 2 DM. (Intest Res 2014;12:139-145)

후드캡을 이용한 대장내시경 검사의 유용성 일반 대장내시경 검사와의 비교 연구

최성원 ( Sung Won Choi ),박희승 ( Hee Seung Park ),이재승 ( Jae Seung Lee ),황상연 ( Sang Yon Hwang ),곽성동 ( Sung Dong Kwak ),최성호 ( Seong Ho Choi ) 대한장연구학회 2012 Intestinal Research Vol.10 No.3

Background/Aims: A few studies showed that hood-cap assisted colonoscopy (CAC) had improved cecal intubation rate and cecal intubation time but did not help in finding colon polyps in comparison with conventional colonoscopy (CC). However, other studies have shown different results. Therefore, we investigated the efficacy of CAC for the cecal intubation time and polyp detection rate. Methods: Patients for colonoscopy in Busan St. Mary`s Medical Center were enrolled to this randomized controlled trial between July 2010 and September 2010. The evaluated outcomes were polyp detection rate, adenoma detection rate, and cecal intubation time in all patients, in difficult cases (history of previous abdominal or pelvic surgery, obesity, old age), and in the expert and non-expert groups. Results: A total of 260 patients enrolled in this study were randomly allocated to the CAC group (n=130), or CC group (n=130). The overall cecal intubation time was shorter in the CAC group (5.7±3.4 min vs. 7.8±5.7 min, P<0.001). The polyp detection rate was higher in the CAC group (58.4% vs. 43%, P=0.008). The cecal intubation time in the expert and non-expert groups were shorter in the CAC group (expert: 4.1±2.2 min vs. 5.5±2.0 min, P=0.001; non-expert: 6.7±3.7 min vs. 9.4±5.9 min, P=0.001). Conclusions: The use of CAC improved the detection rate of colon polyps and shortened the cecal intubation time for both the expert and non-expert groups. (Intest Res 2012;10:280-288)

한국의 1차 의료기관에서 발견된 대장용종: 발견율 및 가이드라인 적용 시 문제점

박상현 ( Sang Hyun Park ),홍광일 ( Kwang Il Hong ),박현철 ( Hyun Chul Park ),김영선 ( Young Sun Kim ),복진현 ( Gene Hyun Bok ),김경호 ( Kyung Ho Kim ),신동석 ( Dong Suk Shin ),한재용 ( Jae Yong Han ),김영관 ( Young Kwan Kim ),최 대한소화기학회 2021 대한소화기학회지 Vol.78 No.6

Background/Aims: There have been few multicenter studies on colonic polyps conducted by primary medical institutions. This study examined the detection rate of colonic polyps in primary health care institutions and the related factors while following the guidelines. Methods: The medical records of 14,029 patients who underwent colonoscopy between January-June 2020 at 40 primary medical institutions in Korea were analyzed. High-risk adenoma was defined as advanced adenoma, carcinoma, or ≥3 adenomas. Results: Most patients (71.2%) aged ≥50 years underwent re-colonoscopy within 5 years (51.3%) for diagnostic purposes (61.3%) in Korean primary medical institutions. The detection rates of colon polyps, adenoma, advanced adenoma, high-risk adenoma, and carcinoma was 59.9%, 38.9%, 5.9%, 11.4%, and 0.3% in all subjects and 59.8%, 37.5%, 8.5%, 12.9%, and 0.3% in average-risk patients, respectively. The incidences of adenoma in average-risk patients increased significantly with age (30s/40s/50s: 20.1%/29.4%/43% for adenoma, 4.4%/6.7%/10.3% for advanced adenoma, and 5.6%/9.5%/14.6% for high-risk adenoma; p<0.05). Before 50 years of age, high-risk adenoma was detected in 9.1% of patients in the first-time screening group, and the significant risk factors were being male and ≥40 years of age. The detection rate of high-risk adenoma in the normal index colonoscopy group within 5 years was 9.0%. The significant risk factors included older age, male sex, positive fecal occult blood test, stool form changes, and nonspecific symptoms (gas and indigestion). Conclusions: More colonic adenoma studies targeting real-world clinical practice will be needed to revise the Korean guidelines for colorectal cancer screening and surveillance. (Korean J Gastroenterol 2021;78:328-336)

대장 내시경의 질 관리 지표로 용종 발견율의 유용성

이수희 ( Su Hee Lee ),박동일 ( Dong Il Park ),성준모 ( Jun Mo Sung ),장재현 ( Jae Hyun Jang ),유승호 ( Seung Ho Ryu ),김영호 ( Young Ho Kim ),이석호 ( Suck Ho Lee ),이창균 ( Chang Kyun Lee ),은창수 ( Chang Soo Eun ),한동수 ( Dong 대한장연구학회 2011 Intestinal Research Vol.9 No.2

Background/Aims: The adenoma detection rate (ADR) has been proposed as a quality indicator of colonoscopy;however, ADR cannot be measured easily with commonly used endoscopy reporting systems because substantial time and effort is required to acquire data from histologic assessments. The purpose of this study was to determine if polyp detection rate (PDR) could be used as a valid proxy for ADR. Methods: A total of 1,156 consecutive,asymptomatic, individuals of average risk between 50 and 75 years-of-age who underwent screening colonoscopies at four tertiary medical centers by 27 gastroenterologists were included in this study. Each individual endoscopist performed at least 10 colonoscopies during the study period. The ADR and PDR were calculated as the proportion of an endoscopist`s cases with an adenoma or polyp divided by the total number of colonoscopies. Pearson`s correlation coefficient and the intraclass correlation coefficient were used to determine the level of agreement between ADR and PDR. Results: The mean PDR and ADR for endoscopists was 47.4% (range, 21.7-75.0) and 36.5% (range,13.0-66.7), respectively. There was a strong correlation between PDR and ADR (Pearson`s correlation coefficient 0.94, P<0.001) and there was also good agreement between performance quintiles defined by ADR and PDR (intraclass correlation coefficient 0.94, P<0.001). Conclusions: PDR is a valid proxy for ADR and may be useful for quality assurance at centers where ADR cannot be easily measured. (Intest Res 2011;9:105-111)

Impact of Moderate versus Deep Sedation and Trainee Participation on Adenoma Detection Rate - Analysis of a Veteran Population

Hemnishil K. Marella,Nasir Saleem,Claudio Tombazzi 대한소화기내시경학회 2021 Clinical Endoscopy Vol.54 No.2

Background/Aims: The adenoma detection rate (ADR) is used as a quality indicator for screening and surveillance colonoscopy. Thestudy aimed to determine if moderate versus deep sedation affects the outcomes of the ADR and other quality metrics in the veteranpopulation. Methods: A retrospective review of colonoscopies performed at Memphis Veterans Affairs Medical Center over a one-year periodwas conducted. A total of 900 colonoscopy reports were reviewed. After exclusion criteria, a total of 229 index, average-risk screeningcolonoscopies were identified. Data were collected to determine the impact of moderate (benzodiazepine plus opioids) versus deep(propofol) sedation on the ADR, polyp detection rate (PDR), and withdrawal time. Results: Among 229 screening colonoscopies, 103 (44.9%) used moderate sedation while 126 (55%) were done under deep sedation. The ADR and PDR were not significantly different between moderate versus deep sedation at 35.9% vs. 37.3% (p=0.82) and 58.2% vs. 48.4% (p=0.13), respectively. Similarly, there was no significant difference in withdrawal time between moderate and deep sedation(13.4 min vs. 14 min, p=0.56) during screening colonoscopies. Conclusions: In veterans undergoing index, average-risk screening colonoscopies, the quality metrics of the ADR, PDR, andwithdrawal time are not influenced by deep sedation compared with moderate sedation.

딥러닝 기반 객체 탐지 알고리즘을 이용한 대장내시경 용종 탐지 시스템

이정남(Jeong-nam Lee),조현종(Hyun-chong Cho) 대한전기학회 2021 전기학회논문지 Vol.70 No.1

In Korea, colon cancer is increasing due to westernized eating habits. Colonoscopy is being used to reduce deaths from colon cancer and studies of CADx(Computer-aided Diagnosis) are being developed to improve accuracy. Due to the nature of medical data, it was difficult to collect a lot of data, so data was increased 25 times using AutoAugment’s CIFAR-10 policy, and YOLOv4(You Only Look Once), a real-time object detection algorithm, was used to detect lesions. A new object detection algorithm, YOLOv4, use new eight features such as Weighted-Residual-Connections, Cross-Stage-Partial-connections, Cross mini-Batch Normalization and Self-Adversarial-Training. The performance of augmented data had a maximum mAP of 27.44 higher than the original data. The average IoU(Intersection over Union) was 11.44 higher than the original data. When the IoU value is 0.5, the F1-scores of the original data and the augmented data are 0.9 and 0.97 respectively.

환자 대장 CT 프로파일을 이용한 전자적 장세척 방법

김한별(Hanbyul Kim),김동성(Dongsung Kim) 한국정보과학회 2008 정보과학회논문지 : 소프트웨어 및 응용 Vol.35 No.8

가상 대장 내시경을 위해서 환자 대장 CT 프로파일을 이용한 전자적 장세척 방법을 제안한다. 제안된 방법은 관강 영역을 cubic seeded region growing(SRG) 방법을 이용하여 추출하고, 이에 인접한 tagged material(TM)을 제거한다. TM의 경계에서 Air-TM의 partial volume(PV) 효과로 발생한 찌꺼기를 제거하고, TM-soft tissue(ST)의 PVE에 의해서 제거된 ST는 환자 CT 프로파일을 이용해서 복원한다. 제안된 방법을 16명의 가상 내시경 환자 CT 데이타에 적용해서 임상의의 주관적인 평가와 computeraided diagnosis(CAD)의 정량적 평가에서 매우 고무적인 결과를 획득했다. This paper proposes an electronic colon cleansing method using a patient CT profile for a virtual colonoscopy. The proposed method extracts the colon using cubic seeded region growing, and removes tagged materials adjacent to the colon. Residuals produced by a partial volume effect at the boundary of air-tagged material are deleted, and the removed soft tissue pixels due to a partial volume effect at the boundary of tagged material-soft tissue are recovered using a patient CT profile. The proposed method was applied to 16 virtual colonoscopy patient data sets, and produced promising results by a subjective evaluation of a radiologist and by a quantitative evaluation of a computer-aided diagnosis system.