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Original Article
FLT3-ITD 검사의 국내 현황 조사(2021)
Status of FLT3-ITD Analysis in Korea (2021)
삼성서울병원 진단검사의학과1, 양산부산대학교병원 진단검사의학과2, 서울아산병원 진단검사의학과3, 연세대학교 세브란스병원 진단검사의학과4, 인제대학교 부산백병원 진단검사의학과5
Department of Laboratory Medicine and Genetics1, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul; Department of Laboratory Medicine2, Pusan National University Yangsan Hospital, Yangsan; Department of Laboratory Medicine3, Asan Medical Center, University of Ulsan College of Medicine, Seoul; Department of Laboratory Medicine4, Yonsei University College of Medicine, Seoul; Department of Laboratory Medicine5, Inje University Busan Paik Hospital, Busan, Korea
Correspondence to:This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Lab Med Online 2023; 13(2): 72-77
Published April 1, 2023 https://doi.org/10.47429/lmo.2023.13.2.72
Copyright © The Korean Society for Laboratory Medicine.
방법: 대학병원 및 3차 의료기관 검사실 책임자에게 전자 메일을 통한 설문을 시행하였다. 설문 문항은 FLT3-ITD 검사에 대한 기관별 검사 이용 및 수행 현황, 검출한계 및 정량한계 검증, 내·외부 정도관리 시행 여부, 결과보고 및 FLT3-ITD 정량 검사에 대한 의견을 포함하였다.
결과: 24개 기관의 회신을 받았다. 설문조사 결과 대부분의 기관에서 FLT3-ITD 확인 및 대립유전자 비율 확인을 위하여 절편분석법을 이용하고 있었다. 대부분의 기관에서 진단 및 경과 관찰 시 FLT3-ITD 대립유전자 비율을 보고하고 있었다. FLT3-ITD 검사에 대한 검사실 자체 검출한계 검증 및 내부정도관리를 시행하고 있었으며 국내외 외부정도관리 프로그램에 참여하고 있었다.
결론: 설문 참여 기관들은 FLT3-ITD 대립유전자 비율의 정확성 및 신뢰도를 높일 수 있는 검사 수행능 검증 및 외부정도관리 필요성에 공감하였다. 본 설문조사 결과가 향후 FLT3-ITD 검사의 표준안 설정에 바탕이 되어 궁극적으로 환자 진료에 긍정적 영향을 미치게 되길 기대한다.
Methods: The survey was conducted through emails to the laboratory directors at university hospitals and tertiary medical institutions. The questionnaires included four questions on the use and performance of FLT3-ITD test by each institution, one on verification of detection and quantification limits, three on internal/external quality control, three on reporting formats and one on the institutions’ opinions on the FLT3-ITD allelic ratio.
Results: Replies were received from 24 institutions. As a result of this survey, it was established that most institutions use fragment analysis to confirm the presence of FLT3-ITD and its allelic ratio. Most institutions reported FLT3-ITD allelic ratios during diagnosis and follow-up. Most laboratories established self-verified detection limits, internal controls, and participated in various external quality control programs for FLT3-ITD test.
Conclusions: Most survey participants agreed on the need for test performance verification and external quality control to increase the accuracy and reliability of FLT3-ITD allelic ratios. We substantiate that the results of this survey will serve as a basis for setting the standard for the FLT3-ITD test in Korea, ultimately having a positive impact on patient care.
Keywords
연구자는 2021년 기준 대한진단검사의학회 회원 중 대학병원 및 3차 의료기관의 검사실 책임자에게 대표로 설문을 보내고 참여 의사를 확인한 후 답변에 응한 24기관의 답변을 분석하였다.
설문 항목은 기관의
설문에 회신한 24기관은 모두
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Table 1 Responses to the questionnaire about the
FLT3 -ITD test in KoreaMultiple Choice Questions % of response (N) 1. How does your institution perform the FLT3 -ITD test?1) Direct sequencing (in-house) 12.5 (3/24) 2) Fragment analysis (in-house) 45.8 (11/24) 3) NGS (in-house) 29.2 (7/24) 4) Direct sequencing (outsourced) 16.7 (4/24) 5) Fragment analysis (outsourced) 41.7 (10/24) 6) NGS (outsourced) 25.0 (6/24) 7) Not performed 0.0 (0/24) 2. Is the FLT3 -ITD quantitative test (allelic ratio) performed?1) Yes (in-house) 37.5 (9/24) 2) Yes (outsourced) 33.3 (8/24) 3) No, but there are plans to implement it (in-house) 4.2 (1/24) 4) No, but there are plans to implement it (outsourced) 4.2 (1/24) 5) No, and there are no plans to implement it 20.8 (5/24) 3. Please choose a quantitative test method for the FLT3 -ITD that is performed directly by your institution.1) Fragment analysis 100.0 (9/9) 2) NGS 33.3 (3/9) 2-1) Capture method 100.0 (3/3) 2-2) Amplicon method 0.0 (0/3) 4. When is the FLT3 -ITD quantitative test performed?1) At diagnosis only 40.0 (6/15) 2) During follow-up only 0.0 (0/15) 3) At diagnosis and during follow-up 60.0 (9/15) 4-1. Describe the timing of the follow-up test 1) Bone marrow examination 57.1 (4/7) 2) After induction of remission, after consolidation therapy, before/after transplantation 14.3 (1/7) 3) Relapse 28.6 (2/7) 5. Has the LOD and LOQ of the FLT3 -ITD quantitative test been verified?1) The LOD and LOQ are verified 0.0 (0/9) 2) Only the LOD is verified 55.6 (5/9) 3) Neither is verified. 44.4 (4/9) 6. Has internal quality control of FLT3 -ITD test been performed?1) Yes 88.9 (8/9) 2) No 11.1 (1/9) 7. Has external quality control of the FLT3 -ITD test been performed?1) Yes 100.0 (9/9) 2) No 0.0 (0/9) 8. If the FLT3 -ITD quantitative test is added to the external quality control program, are you willing to participate?1) Yes 100.0 (9/9) 2) No 0.0 (0/9) 9. How many days do you think is appropriate as a TAT for the FLT3 -ITD quantitative test?1) 7 days 36.8 (7/19) 2) 10 days 31.6 (6/19) 3) 15 days 21.1 (4/19) 4) Others 10.5 (2/19) 10. How is the reporting form for allelic ratio described? 1) Only allelic ratio is described 77.8 (7/9) 2) The allelic ratio and mutant length are described 22.2 (2/9) 11. How is the allelic ratio calculated? 1) FLT3 -ITD peak area/FLT3-wild type peak area88.9 (8/9) 2) FLT3 -ITD peak height/FLT3-wild type peak height11.1 (1/9) Abbreviations: NGS, next-generation sequencing; LOD, limit of detection; LOQ, limit of quantification; TAT, turnaround time.
1. FLT3 -ITD 검사의 현황
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Table 2 Summary of
FLT3 -ITD test utilization by Korean institutionsFLT3 -ITD test utilization by institutions% of institution (N) Location of FLT3 -ITD testIn-house 37.5 (9/24) Outsourced 41.7 (10/24) Both in-house and outsourced 20.8 (5/24) FLT3 -ITD test typeFragment analysis 87.5 (21/24) NGS 54.2 (13/24) Direct sequencing 29.2 (7/24) Number of FLT3 -ITD test methods in useN= 1 33.3 (8/24) - Fragment analysis 25.0 (6/24) - Direct sequencing 8.3 (2/24) - NGS 0.0 (0/24) N= 2 62.5 (15/24) - Fragment analysis and NGS 45.8 (11/24) - Fragment analysis and direct sequencing 12.5 (3/24) - Direct sequencing and NGS 4.2 (1/24) N= 3 (all methods) 4.2 (1/24) Abbreviation: NGS, next-generation sequencing.
검사방법을 두 가지 이상 시행하는 이유에 대해 주관식으로 질문하였고 결과는 다음과 같았다. 절편분석법과 NGS법을 둘 다 시행하는 이유로 결과보고시간 단축을 위해(5기관), 정확한 정량 검사를 위해(4기관), 검사 방법 간 민감도의 차이 때문(4기관), 혈액암 NGS 패널검사 및 절편분석법을 병행하여 검사하기 때문(2기관), AML 추적 관찰 시 정량 검사를 위해(1기관)라고 답하였다. 절편분석법과 직접염기서열분석을 같이 시행하는 이유는 정성 및 정량 검사를 모두 시행하기 위한 목적(3기관)이었으며, 직접염기서열분석과 NGS법을 같이 시행하는 1기관은 혈액암 NGS 패널검사를 시행하지 않는 경우 직접염기서열분석법으로
2. FLT3 -ITD 정량 검사의 검출한계 및 정량한계 검증
3. FLT3 -ITD 검사의 내·외부 정도관리 현황
4. FLT3 -ITD 정량 검사의 결과보고 및 기타 의견
주관식 질문으로
AML에서
AML에서 미세잔존질환의 확인을 위해서는 최소 0.1% 이상의 민감도를 갖는 검사법을 이용해야 한다[19]. 따라서,
설문조사 시 원내에서
본 설문조사 시행 시 일부 주관식 답변을 요구하는 설문의 경우 객관식 문항에 비해 응답률이 떨어지는 한계가 있었다.
이번 설문조사를 통해 국내 검사실의
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