en Medical Biology Medical Biology مقاله پژوهشی Original Research Article <p style="text-align: justify;"><span style="font-family:times new roman;"><span style="font-size:14px;"><span style="color:#008080;"><strong>Background & Objective:</strong></span> FLT3-ITD mutation detection has been an integral part of diagnostic work ups focused on acute myeloid leukemia. However, some studies have indicated that the mutation is unstable during the various stages of the disease. The purpose of this study was to evaluate the stability of this marker in paired diagnosis-relapse samples using Delta-PCR&nbsp;method.<br> <span style="color:#008080;"><strong>Materials & Methods:</strong></span> In this retrospective study, paired diagnosis-relapse bone marrow or peripheral blood samples from 180 adult AML patients were analyzed for FLT3-ITD mutations using conventional fragment analysis and Delta-PCR methods. A dilutional experiment of DNA derived from a FLT3-ITD mutated patient in normal peripheral blood was performed in order to evaluate the sensitivity of each method.<br> <span style="color:#008080;"><strong>Results: </strong></span>All samples were analyzed using both conventional fragment analysis and Delta-PCR methods. FLT3-ITD mutations were detected in 24 diagnostic samples (13.3%) and 28 relapse samples (15.5 %) through conventional fragment analysis. Three out of four patients who were FLT3-ITD positive in the relapse samples had a mutation in the diagnostic samples using the Delta-PCR method. On the other hand, at the time of diagnosis and relapse, the mutation test results were incompatible in only 3.6% of patients based on the results of the Delta-PCR method compared to 14.2 based on conventional fragment analysis. Our findings revealed that the sensitivity of Delta - PCR as related to FLT3-ITD detection was 0.2 %. Compared to the conventional fragment analysis, with a sensitivity of 2%, Delta - PCR shows greater sensitivity and specificity.<br> <span style="color:#008080;"><strong>Conclusion: </strong></span>The conventional testing of the FLT3-ITD mutation by fragment analysis did not detect a significant proportion (11%) of FLT3-ITD positive samples in AML patients. Delta PCR increased the sensitivity and specificity relative to the conventional method. The detection of FLT3-ITD mutation through Delta PCR is important in order to detect minor clones at diagnosis or during the monitoring of AML patients.</span></span></p> Acute myeloid leukemia, Delta-PCR, FMS-like tyrosine kinase, Internal tandem duplication 38 44 http://journal.zums.ac.ir/browse.php?a_code=A-10-5010-1&slc_lang=en&sid=1 Maryam Arab مریم عرب arabma2019@gmail.com 5200319475328460088683 5200319475328460088683 No Dept. of Hematology and Blood Banking, Faculty of Allied Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran. Shahrbano Rostami شهربانو رستمی drostamy@yahoo.com 5200319475328460088684 5200319475328460088684 No Hematology, Cell Therapy and Hematopoietic Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran. Nasrin Alizad Ghandforoush نسرین علی‌زاد قندفروش Alizad_n@yahoo.com 5200319475328460088685 5200319475328460088685 No Hematology, Cell Therapy and Hematopoietic Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran. Mohsen Nikbakht محسن نیک‌بخت mohsennik@yahoo.com 5200319475328460088686 5200319475328460088686 No Hematology, Cell Therapy and Hematopoietic Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran. Saeed Mohammadi سعید محمدی Saeedm-58@yahoo.com 5200319475328460088687 5200319475328460088687 No Dept. of Hematology and Blood Banking, Faculty of Allied Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran. Arvin Samemaleki آروین سام ملکی arvin.sam2019@gmail.com 5200319475328460088688 5200319475328460088688 No Dept. of Hematology and Blood Banking, Faculty of Allied Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran. Kamran Alimoghaddam کامران علی‌مقدم alimogh@yahoo.com 5200319475328460088689 5200319475328460088689 No Associate Professor Bahram Chahardouli بهرام چهاردولی Chbahram@yahoo.com 5200319475328460088690 5200319475328460088690 Yes Assistant professor