Quantitative immunochemical tests: evidence on accuracy and implementation considerations in the Czech MUDr.. Petr Kocna, CSc. European Digestive Cancer Days, Prague - 26. September 2017
QUANTITATIVE FIT FOR CRC SCREENING Quantitative FIT are replacing traditional guaiac FOBT in population screening programs for many reasons. Quantitative FIT achieves 90% sensitivity for CRC detection and is therefore at least 3 times more sensitive than guaiac test Quantitative FIT needs to be optimised for population screening with professional, epidemiological and economic aspects Quantitative FIT offer much more than just FOBT+/ +/FOBT- results, and FIT cut-off could significantly modify the screening programs Quantitative FIT are developed over 20 years, and over the past 20 years there are 5189 publications in MEDLINE (09/2017) 2
Can.J.Gastro.Hepatol. - 06/2016 Quantitative one FIT test (NS-Plus, Alfresa) ) with cut-off 10 μg/g 20 322 FIT positive subjects underwent colonoscopy. Cut-off 10 μg/g with all adenoma detection exceeds national recommendations 60 and endoscopic sources need to be considered. 50 40 30 20 10 CRC - cancer adenoma high-risk adenoma low-risk 3 0 10-15 15-20 20-40 40-100 > 100 μg/g Shahidi N. Gentile L. Gondaraet L. al.: Can.J.Gastro.Hepatol.. 2016 Correlating Quantitative Fecal Immunochemical Test Results with Neoplastic Findings on Colonoscopy in a Population-Based Colorectal Cancer Screening Program.
FIT ANALYSIS, FAECALF Hb CONCENTRATION, CUT-OFF Probability HEALTHY SUBJECTS ADENOMA LOW-RISK ADENOMA HIGH-RISK COLORECTAL CANCER 4 0 10 20 30 40 50 60 70 80 90 100 110 120 140 160 cut-off FIT cut-off gfobt μg/g
FIT 50 ng/ml (10 μg/g) FIT positivity 8-11 % Adenoma detection approx. 50 % CRC detection - 6,7 Effort to increase Sensitivity and Higher financial efficiency FIT 100 ng/ml (20 μg/g) Adenoma detection approx. 30 % CRC detection - 4,7 High false positivity Decrease number of colonoscopies gfobt positivity 3-5 % CRC detection - 3,1 FIT 200 ng/ml (40 μg/g) 5
SETTING THE CUT-OFF VALUE FIT TEST - FIT OPTIMISATION Determine sensitivity - rate of detected neoplasma /CRC Determine specificity - the numbers of 'unnecessary' colonoscopies Decide required capacity of GE centers and screening costs Accuracy and reliability of Hb analysis in stool 6 Standardization of FIT analysis Transferability of FIT analysis results External quality control of FIT analysis
J Natl Cancer Inst - 04/2012 Faecal immunochemical tests for Hb are replacing traditional guaiac faecal occult blood tests in population screening programs for many reasons. Many available faecalf immunochemical test devices use a range of sampling methods, differ with sampling methods, buffer volume and characteristics, Hb stability and results are expressed by different way. The current lack of consistency in units for Hb concentration is particularly problematic because apparently similar Hb concentrations obtained with different devices can lead to very different clinical interpretations. Consistent adoption of an internationally accepted method for reporting r results would facilitate comparisons of outcomes from these tests. We propose a simple strategy for reporting faecal Hb concentration 7 Fraser CG, Allison JE, Halloran SP, Young GP, Expert Working Group on Fecal Immunochemical Tests for Hemoglobin,, Colorectal Cancer Screening Committee WEO.. J Natl Cancer Inst 2012;104:810 14. 14. A proposal to standardize reporting units for fecal immunochemical tests for hemoglobin.
WEO Expert Working Group (EWG) Colorectal Cancer Screening Committee (CRC SC) First WG-FIT Meeting Euromedlab Athens 14. June 2017 IFCC Scientific Division Working Group Fecal Immunochemical Testing (WG-FIT) 8 To harmonise and/or standardise analysis of haemoglobin in faecal samples by immunochemistry (FIT)
J Lab Med Qual Assur - 10/2016 External quality control in Korea - in 2015 EQA analysis was conducted 3x during the year - 1,250 participants Qualitative tests - 569 participants (71%) - 9 different methods Qualitative tests provide false-positive results The success of the qualitative samples for negative sample was only 11% Quantitative FIT test - 235 participants (29%) - 7 different analyzers Totally different results depending on the technique used - in ng/ml 9 Chang-Ho Jeon and A-Jin A Lee, J Lab Med Qual Assur 2016;38:120-128 128 Annual Report on the External Quality Assessment Scheme for Urinalysis and Faecal Occult Blood Testing in Korea (2015)
FIT REALIZED BY GENERAL PRACTITIONER IN CZECH - 2014 QUESTIONNAIRE FOR PRACTITIONERS n = 522 g-fobt 3% Laboratory FIT 7.5% POCT FIT 23.5% Qualitative FIT 66% - 13 different methods - rapid tests 10 Král N., Seifert B., Korcová M.: Variability tests for occult blood used by general practitioners in screening for colorectal cancer in the Czech Republic. Gastroent Hepatol 2015 69(3): 255 258 258
ng/ml 250 225 200 175 150 125 100 11 /ml J Lab Med Qual Assur - 10/2016 75 50 25 0 POSITIVE SAMPLE NEGATIVE SAMPLE EQA Korea 2015 235 participants (29%) 7 different analyzers Results in ng/ml Chang-Ho Jeon and A-Jin A Lee, J Lab Med Qual Assur 2016;38:120-128 128 Annual Report on the External Quality Assessment Scheme for Urinalysis and Faecal Occult Blood Testing in Korea (2015) cut-off Eiken Eiken Eiken Alfresa Alfresa Kyowa Kyowa Micro Diana Io NS-1000 NS-C C HM-Jack HM-Jack Arc
Hb QUANTITATIVE ANALYSIS - FIT in CZECH REPUBLIC 12 External quality assessment Hb determination in the stool started in January 2012, as a part of the national EQA EQA programme provided by SEKK member of EQALM accredited ISO/IEC IEC 17043:2010 90 users in the Czech Republic EQA in Czech Republic - 2 liquid samples, twice per year
FIT EXTERNAL QUALITY ASSESSMENT IN CZECH REPUBLIC April 2016 μg/g Data from cycle FOB 2016-01 Eiken OC-Sensor Sentinel FOBGold CV - 8.10 % CV - 8.85 % FOB Gold analysis sample A - 50 μg/g sample B - 140 μg/g OC-Sensor analysis sample A - 30 μg/g sample B - 80 μg/g 1,6x higher 13 Kocna P., Zima T., Budina M., Ichiyanagi T.: External Quality Assessment ((EQA) for Quantitative Fecal Blood in Stool (FIT). Biochimica Clinica,, 2013, 37, 423
Gastroenterology - 03/2017 Screening with cut-off 15 μg/g according to OC-Sensor - Eiken study Predicted positivity - 6.3 % Screening done with the test FOB Gold - Sentinel FIT test positivity - 12.2 % 14 Cut-off has been modified to 47 μg/g to effort positivity 6.3 % Toes-Zoutendijk E, van Leerdam ME, Dekker E et all. : Real-Time Monitoring of Results During First Year of Dutch Colorectal Cancer Screening Program and a Optimization by Altering Fecal Immunochemical Test Cut-Off Levels. Gastroenterology 2017;152:767 775 775
Epidemiology of colorectal cancer: comparison of Czech regions FIT positivity in individual districts could be significantly affected by the FIT method used DC: 7,0 UL: 7,0 LI: 6,1 TP: 5,5 MO: 6,4 CL: 9,5 JN: 9,7 CV: 5,2 LT: 7,1 SM: 6,9 TU: 9,8 SO: 4,6 KV: 5,9 LN: 8,5 ME: 7,8 MB: 6,6 JC: 6,8 NA: 7,8 CH: 7,7 KD: 6,5 RA: 8,6 PH: 8,9 NB: 6,0 HK: 8,0 AX: 9,2 RK: 8,0 PS: 6,8 JE: 4,9 TC: 9,2 BE: 8,6 PZ: 7,6 KO: 7,6 PA: 5,9 RO: 11,4 PM: 7,2 UO: 8,2 KH: 9,3 SU: 5,9 BR: 8,2 CR: 6,7 PB: 7,5 PJ: 6,3 BN: 11,6 DO: 13,3 OP: 6,5 HB: 6,0 SY: 6,9 OT: 5,9KA: 4,6 PI: 6,5 OL: 6,4 KT: 5,2 TA: 6,1 PE: 6,8 ZR: 8,8 NJ: 6,3 ST: 8,6 BK: 6,2 PV: 6,9 PR: 6,5 JI: 6,8 FM: 7,5 PT: 9,2 BO: 6,9 JH: 8,7 VS: 6,2 TR: 8,6 BM: 7,6 VY: 8,5 KM: 6,6 CB: 6,8 ZL: 5,1 CK: 4,0 ZN: 6,8 BV: 7,2 Test positivity <5,0 5,0 6,5 6,5 8,0 8,0 9,5 > 9,5 Total positivity (2016) : 7.2 % Range UH: 6,7 HO: 6,4 between districts : 4,0 13,3 % 15 Májek O., Suchánek Š. Quality-assured assured immunochemical testing proposal for a pilot project in the Czech Republic European Digestive Cancer Days, Prague - 26. September 2017
TAKE HOME MESSAGE Efforts to change qualitative FIT to quantitative FIT Efforts to change units from ng/ml to μg/g of stool Standardization of FIT methods according to IFCC committee Essential requirement for FIT external quality control Personalized approach to FIT analysis of Hb in faeces Screening programs modifications using FIT values 16