Aim. To assess the rate of DNMT3A, IDH1, IDH2, and ASXL1 gene mutations and their effect on the prognosis both as isolated findings and in combination with well-known chromosomal aberrations and gene mutations in newly diagnosed acute myeloid leukemia (AML) patients from some regions of the Russian Federation. Materials & Methods. The study enrolled 83 patients with newly diagnosed AML from 22 regions of the Russian Federation, who underwent molecular genetic examination for detecting IDH1 (R132), IDH2 (R140), ASXL1, and DNMT3A gene mutations with droplet digital PCR and Sanger sequencing methods. Results. The mutation rate in DNMT3A was 16.7 %, in IDH1 (R132) it was 6 %, in IDH2 (R140) it was 9.6 %, and in ASXL1 it was 6 %. The R140 mutation in IDH2 correlated with the older age of patients. The mutations in IDH1 (R132), IDH2 (R140), and DNMT3A showed a significant association with mutated NPM1. The mutations in IDH1 (R132), IDH2 (R140) were reported to occur significantly more often in patients with normal karyotype. The IDH1 (R132) and IDH2 (R140) mutations appeared to have a favorable effect on AML prognosis, which is most likely to be associated with a high rate of their compatibility with NPM1 mutation. The mutated type of DNMT3A had a negative effect on overall survival of patients with NPM1 mutation. The mutation in ASXL1 also appeared to be an unfavorable prognostic factor for overall survival of patients with wild type NPM1. Conclusion. A high rate of mutation occurrence in epigenetic regulation genes as well as the prognostic potential of these mutations in AML necessitate the need for determining the mutation status of DNMT3A, IDH1, IDH2, and ASXL1 in the context of primary diagnosis in real-world clinical practice.

Acute myeloid leukemias (AML) are the most ubiquitous of all adult leukemias. The prognosis of the disease depends on its genetic profile. The mutation in FLT3 gene, which codes FMS-like tyrosine kinase 3, is observed in 1/3 of patients and is responsible for a high rate of relapses. The prognosis of relapsed/refractory FLT3-positive AML is extremely poor. The standard intensive therapy rarely yields long-term responses. The new first- and second-generation FLT3 tyrosine kinase inhibitors enriched treatment opportunities for patients with this mutation. Gilteritinib, a potent second-generation FLT3-ITD/TKD inhibitor, is a new effective and well tolerated drug for the treatment of relapsed/refractory FLT3-positive AML. Due to its efficacy, low toxicity, and good manageability, this drug can be administered to all patients, including the elderly or those with severe comorbidities and complications of previous therapy. Besides, this drug can be used in outpatient units. The present paper contains three case reports dealing with different clinical situations in patients with FLT3-positive AML treated with gilteritinib in real-world clinical practice.

Internal tandem duplication is the most common form of mutation in FMS-like tyrosine kinase 3 (FLT3) in different haematological malignancies, highlighting in acute myeloid leukaemia (AML) and is associated with increased risk of relapse and reduced overall survival. A major breakthrough in the treatment of FLT3-mutated AML has been achieved through the use of highly selective FLT3 tyrosine kinase inhibitors, both in monotherapy and in combination with standard intensive cytotoxic chemotherapy. The desire to improve the outcomes of patients with AML, including those with relapse and refractory disease, has led to attempts to use non-standard therapeutic options. Enhancement of the antileukemic effects of the second-generation FLT3 inhibitor Gilteritinib may be achieved through synergy with the hypomethylating agent 5-azacytidine and the selective Bcl-2 inhibitor Venetoclax. Thus, targeted triple therapy is a promising option in the treatment of patients with FLT3-mutated AML. This study sought to evaluate the effectiveness of “triple therapy” regimen in 4 patients with relapsed/refractory FLT3 mutated AML. We found that the use of this combination showed rapid response with good safety and frequently allowed subsequent transplant and achieve durable clinical benefit.

Aim. To identify mutations in IDH1/IDH2, DNMT3A, and ASXL1 genes responsible for genome epigenetic regulation and their co-occurrence with FLT3, NPM1, and RUNX1 mutations in newly diagnosed adult acute myeloid leukemias (AML). Materials & Methods. The study included 56 patients with newly diagnosed AML treated at the VA Almazov National Medical Research Center. Among them there were 34 men and и 22 women aged 18-76 years (median 46 years). Mutation status of IDH1, IDH2, DNMT3A, and ASXL1 genes of epigenetic regulation was assessed by Sanger sequencing method. Molecular genetic analysis of FLT3, NPM1, and RUNX1-RUNX1T1 genes was performed using commercial kits. Results. Mutations in epigenetic regulation genes were detected in 14 (25 %) out of 56 patients. Mutation prevalence was not associated with risk groups (p = 0.072). IDH1/2 mutations were identified in 15.6 % of patients and were significantly oftener observed concurrent with NPM1 mutations (62.5 %; p = 0.01) compared to patients with wild-type IDH1/2. In most patients IDH1/2 mutations were associated with normal karyotype (p = 0.002). The DNMT3A (R882) mutation was identified in 4 (7.1 %) out of 56 patients within the analyzed group. In 6 patients (11.1 %) ASXL1 mutations were detected co-occurring with RUNX1-RUNX1T1 and FLT3-ITD mutations. Conclusion. Mutations in epigenetic regulation genes are often identified in AML patients and can be concurrent with abnormalities in NPM1, FLT3 и RUNX1 genes.

Цель. Выявление мутаций генов IDH1/IDH2, DNMT3A и ASXL1, ответственных за эпигенетическую регуляцию генома, при впервые диагностированных острых миелоидных лейкозах (ОМЛ) у взрослых и их сочетания с мутациями генов FLT3, NPM1, RUNX1. Материалы и методы. В исследование включено 56 пациентов с впервые выявленным ОМЛ, проходивших лечение в ФГБУ «НМИЦ им. В.А. Алмазова» Минздрава России. Среди них было 34 мужчины и 22 женщины в возрасте 18–76 лет (медиана 46 лет). Мутационный статус генов эпигенетической регуляции IDH1, IDH2, DNMT3A и ASXL1 определяли методом секвенирования по Сэнгеру. Молекулярно-генетический анализ генов FLT3, NPM1, RUNX1-RUNX1T1 выполняли с использованием коммерческих наборов. Результаты. Мутации генов эпигенетической регуляции обнаружены у 14 (25 %) из 56 пациентов. Распространенность мутаций не была связана с группами риска (p = 0,072). Мутации IDH1/2 выявлены у 15,6 % пациентов и статистически значимо чаще обнаруживались одновременно с мутациями NPM1 (62,5 %; p = 0,01) по сравнению с пациентами с диким типом IDH1/2. У большинства пациентов мутации IDH1/2 были связаны с нормальным кариотипом (p = 0,002). Мутация DNMT3A (R882) определена у 4 (7,1 %) из 56 пациентов анализируемой группы. У 6 (11,1 %) пациентов были идентифицированы мутации ASXL1, которые сочетались мутациями с RUNX1-RUNX1T1 и FLT3-ITD. Заключение. Мутации генов эпигенетической регуляции часто обнаруживаются у пациентов с ОМЛ и могут сочетаться с нарушениями в генах NPM1, FLT3 и RUNX1.

Dysfunction of genes that control mitosis and are responsible for the correct segregation of sister chromatids in anaphase is often accompanied by aneuploidy, which is frequently detected in leukemia. One of the components of the kinetochore complex, namely, the AF15q14/KNL1/CASC5 protein, is an important factor ensuring the correct binding of the pericentromeric region of chromosomes with the spindle microtubules. As shown recently, in some leukemias, the gene of this protein can be involved in the generation of the chromosomal translocation t(11;15)(q23;q14) or a variant of the chimeric MLL-AF15Q14 oncogene, which serves as a biomarker of poor prognosis. Despite the implication of mRNA of the CASC5 gene in oncogenesis of solid tumors, expression of this gene in hematopoietic neoplasms has not been studied. We analyzed expression levels of the CASC5 gene and the nearest regulatory genes, including WT1, APOBEC3A (A3A), and N-MYC. A pronounced decrease in CASC5 expression in bone marrow cells of primary leukemia patients compared with healthy donors was found. It was also shown that reduced expression of the CASC5 gene correlates with the detection of targeted mutations in patients composed two prognostic subgroups (favorable, unfavorable) with a significance level (p <0.05). It was noted that the change in the expression level of the CASC5 gene in acute myeloid leukemia is associated with overexpression of the genes WT1, A3A, and in some cases N-MYC and SPT16, which is consistent with the resistance to chemotherapy and leukemia progression. However, the question of which regulatory gene initiates leukemogenesis remains open.

NK-cells as innate immunity elements manifest key reactions of antitumor immune response. NKG2D is an activating transmembrane receptor of NK-cells which is responsible for cytotoxicity initiation in response to the binding of specific ligands of genetically modified cells. Selective expression of NKG2D ligands provides a unique perspective on the therapy of wide variety of tumors. Acute myeloid leukemias (AML) are malignant hematological tumors with a high relapse risk. Due to the complexity of AML treatment strategy it is necessary to develop new approaches to tumor elimination using novel genetic constructs. Currently available CAR T-cell drugs with NKG2D receptor are successfully subjected to clinical studies in AML patients and prove their high therapeutic potential.

Актуальность. До настоящего времени показатели выживаемости пациентов с острыми миелоидными лейкозами (ОМЛ) остаются неудовлетворительными. Для успешного лечения ОМЛ необходимо создание персонализированных моделей этого заболевания. Наиболее перспективным направлением в данной области является разработка ксенографтных моделей от больных ОМЛ с использованием наиболее современной линии иммунодефицитных «гуманизированных» мышей NSG-SGM3. Цель. Создание ксенографтных моделей от больных ОМЛ с использованием иммунодефицитных мышей линии NSG-SGM3. Материалы и методы. Для создания PDX-моделей использовались образцы аспирата костного мозга 4 пациентов с впервые диагностированным ОМЛ, проходивших лечение в ФГБУ «НМИЦ им. В.А. Алмазова» МЗ РФ. Опухолевые клетки от пациентов трансплантировали мышам линии NSG-SGM3. Для проведения контрольного эксперимента мышам NSG-SGM3 вводили клетки линий ОМЛ: OCI-АМL2 и HL60. Эффективность приживления образцов опухоли оценивалась на основе физического состояния животных и лабораторных исследований (формула крови, мазок крови, ПЦР, проточная цитофлюориметрия). Результаты. Приживление введенных опухолевых клеток от 4 пациентов с ОМЛ достигнуто у половины (2 из 4) мышей. У 2 мышей с успешной трансплантацией имел место лейкоцитоз. Бластные клетки обнаруживались в периферической крови на 30-й день после трансплантации. У мышей с инъецированными клеточными линиями ОМЛ OCI-АМL2 и HL60 наблюдалось более агрессивное течение заболевания. Среди протестированных подходов для оценки приживления опухоли у мышей-реципиентов метод ПЦР отличался наибольшей чувствительностью. Заключение. Использование иммунодефицитных «гуманизированных» мышей линии NSG-SGM3 позволяет успешно получать ксенографтные модели от пациентов с ОМЛ.

Миелоидная саркома (известная как хлорома или гранулоцитарная саркома) представляет собой редкое заболевание и характеризуется пролиферацией незрелых миелоидных клеток в экстрамедуллярных очагах поражения. Хлорома чаще развивается у пациентов с острыми миелоидными лейкозами, другими миелопролиферативными новообразованиями или миелодиспластическим синдромом, однако также может манифестировать в виде изолированной опухоли. Хотя миелоидная саркома может развиваться в различных органах и тканях, все же наиболее часто встречается поражение лимфатических узлов, мягких тканей и костей. Миелоидная саркома с первичным поражением женских половых органов описывается крайне редко. В литературе есть клинические наблюдения поражения шейки матки. В настоящей статье суммированы имеющиеся литературные данные, затрагивающие различные аспекты диагностики и лечения миелоидной саркомы. Обсуждается роль химиотерапии, лучевой терапии, хирургического вмешательства и трансплантации костного мозга в лечении данной злокачественной опухоли. Представляется, что оптимальным вариантом лечения миелоидной саркомы независимо от первичной локализации опухоли остается химиотерапия и трансплантация аллогенного костного мозга (аллоТКМ). Перспективным направлением в терапии является использование новых таргетных препаратов, способных улучшить результаты лечения. Мы представляем клиническое наблюдение пациентки с миелоидной саркомой шейки матки и сопутствующим вовлечением костного мозга, описываем особенности клинического течения, диагностики и лечения. Пациентка получила химиотерапию с последующей аллоТКМ. Проведенный объем предтрансплантационной терапии позволил выполнить аллоТКМ при максимально глубоком ответе. У пациентки достигнута ПЭТ- и МОБ-отрицательная полная ремиссия миелоидной саркомы шейки матки и костного мозга.

Background. Up to the present the survival rates of acute myeloid leukemia (AML) patients have remained low. A successful AML management presupposes generating personalized models of the disease. The most promising research activity in this field is creation of AML patient-derived xenograft models using the advanced strain of immunodeficient humanized NSG-SGM3 mice. Aim. To generate AML patient-derived xenograft models using immunodeficient NSG-SGM3 mice. Materials & Methods. The creation of PDX models was based on bone marrow aspirates taken from 4 patients with newly diagnosed AML who were treated at the V.A. Almazov National Medical Research Center. Patient-derived tumor cells were transplanted to NSG-SGM3 mice. Test experiment consisted in injecting AML cells OCI-АМL2 and HL60 in NSG-SGM3 mice. The efficacy of tumor engraftment was evaluated in terms of physical condition of animals and laboratory tests (blood count, blood smear, PCR, and flow cytofluorometry). Results. The engraftment of applied tumor cells derived from AML patients was achieved in half (2 out of 4) of the transplanted tumor samples. In mice with successful transplantation leukocytosis was reported. Blast cells were identified in peripheral blood on Day 30 after transplantation. The mice with injected AML cells OCI-АМL2 and HL60 showed a more aggressive course of disease. Among tested approaches to evaluate tumor engraftment in mouse recipients, the PCR method was marked by highest sensitivity. Conclusion. The use of immunodeficient humanized NSG-SGM3 mice enables successful generation of AML patient-derived xenograft models.

Aim. To assess the efficacy, safety, and tolerance of gemtuzumab ozogamicin (GO) combined with FLAG/FLAG-Ida chemotherapy or azacitidine in patients with relapsed/refractory acute myeloblastic leukemia (AML) in clinical practice. Materials & Methods. The study included 32 patients (16 men and 16 women). The median age was 44 years (range 23-83 years). Among them there were 15 (46.8 %) patients with refractory and 17 (53.2 %) patients with relapsed AML. GO combined with FLAG/FLAG-Ida was administered to 15 (46.8 %) patients, whereas 17 (53.2 %) patients were treated with GO and azacitidine combination. Therapy safety was assessed according to CTCAE v. 5.0. Results. Overall response rate including complete remission (CR), CR MRD-, CR with incomplete hematologic recovery, and morphologic leukemia-free status was 59.4 % (19/32). Refractoriness was observed in 31.25 % (10/32) of patients. Early mortality was 9.4 % (3/32). Overall response was 64.7 % (11/17) in the azacitidine and 53.3 % (8/15) in the FLAG/FLAG-Ida groups. In 4 (80 %) out of 5 patients with prior to FLAG treatment refractoriness, the response was achieved after GO + azacitidine therapy. In 58.9 % (10/17) of patients who received GO + azacitidine therapy, allogeneic hematopoietic stem cell transplantation (allo-HSCT) could be performed. The incidence of GO infusion complications in the tested groups did not significantly differ (p = 0.72) and was 46.7 % (7/15) (40 % with grade 1/2 and 6.7 % with grade 3) in the GO + FLAG/FLAG-Ida group and 35.3 % (6/17) (29.4 % with grade 1/2 and 5.9 % with grade 4) in the GO + azacitidine group. In the GO + FLAG/FLAG-Ida group 5 (33.3 %) patients experienced serious adverse events (SAE) of sepsis. In the GO + azacitidine group SAEs were reported in 6 (35.3 %) patients: 4 (66.6 %) with sepsis, 1 (16.7 %) with acute cardiovascular failure, and 1 (16.7 %) with acute respiratory failure. The median (range) duration was 23 (10-39) days for neutropenia grade 4, 24 (11-38) days for neutropenia grade 3, 21 (11-41) days for thrombocytopenia grade 4, 26 (16-45) days for thrombocytopenia grade 3, and 25 (22-45) days for thrombocytopenia grade 1/2. Thrombocytopenia duration was longer in patients with GO + FLAG/FLAG-Ida therapy, however, no significant differences were identified. No cases of veno-occlusive liver disease were reported. Median overall survival (OS) for both groups (n = 32) was 31.4 months, median disease-free survival (n = 21) was 13.3 months. In the group of patients with effective treatment, the median OS was not reached. In non-responders, it was 18 months (р = 0.0442). Conclusion. GO combined with FLAG/FLAG-Ida chemotherapy or azacitidine proved effective in relapsed/refractory AML patients. Remission did not appear to be associated with ELN risk, gender, age, CD33 expression, number of prior therapy lines, or number of relapses. GO + azacitidine combination showed efficacy, safety, and good tolerance in patients with prior high-dose chemotherapy refractoriness as well as low ECOG performance status. That allowed for the subsequent allo-HSCT administration to these patients. There was no significant difference between the groups of patients in the incidence of hematologic, non-hematologic toxicity, and time to hematologic recovery. Thrombocytopenia duration was longer in patients with GO + FLAG/FLAG-Ida therapy which is consistent with literature data. GO-based effective treatment in relapsed/refractory AML considerably improves OS: during 36 months of follow-up the median was not reached.

NK-клетки как элементы врожденного иммунитета реализуют ключевые реакции противоопухолевого иммунного ответа. NKG2D — активационный трансмембранный рецептор NK-клеток, ответственный за инициацию цитотоксичности в ответ на связывание специфичных лигандов генетически модифицированных клеток. Селективная экспрессия лигандов NKG2D открывает уникальные перспективы для терапии широкого спектра опухолей. Острые миелоидные лейкозы (ОМЛ) — это злокачественные опухоли системы крови, характеризующиеся высоким риском развития рецидивов. Сложность терапевтической стратегии при ОМЛ создает необходимость поиска новых подходов к элиминации опухоли с применением инновационных генетических конструкций. Имеющиеся к настоящему времени CAR T-клеточные препараты, несущие рецептор NKG2D, успешно изучаются в клинических исследованиях у пациентов с ОМЛ, доказывая свой высокий терапевтический потенциал.

Цель. Оценить эффективность, безопасность и переносимость гемтузумаба озогамицина (ГО) в комбинации с химиотерапией FLAG/FLAG-Ida или азацитидином у пациентов с рецидивами и рефрактерным течением острого миелобластного лейкоза (ОМЛ) в реальной клинической практике. Материалы и методы. В исследование включено 32 пациента (16 мужчин, 16 женщин). Медиана возраста составила 44 года (диапазон 23–83 года). Среди них было 15 (46,8 %) пациентов с рефрактерным течением ОМЛ и 17 (53,2 %) — с рецидивами. ГО в комбинации с режимами FLAG/FLAG-Ida использовался у 15 (46,8 %) пациентов, в комбинации с азацитидином — у 17 (53,2 %). Безопасность терапии оценивалась согласно шкале CTCAE v. 5.0. Результаты. Частота общего ответа, включающего полную ремиссию (ПР), ПР МОБ–, ПР с неполным восстановлением показателей крови, морфологически свободный от лейкоза статус, составила 59,4 % (19/32). Рефрактерность наблюдалась у 31,25 % (10/32) пациентов. Ранняя летальность составила 9,4 % (3/32). Общий ответ в группе с азацитидином составил 64,7 % (11/17), с FLAG/FLAG-Ida — 53,3 % (8/15). У 4 (80 %) из 5 пациентов с рефрактерностью к предшествующему лечению по схеме FLAG достигнут ответ после терапии ГО + азацитидин. У 58,9 % (10/17) пациентов после терапии ГО + азацитидин удалось выполнить трансплантацию аллогенных гемопоэтических стволовых клеток (аллоТГСК). Частота инфузионных осложнений ГО в группах статистически значимо не различалась (p = 0,72) и составила 46,7 % (7/15) (40 % — I–II степени, 6,7 % — III степени) в группе ГО + FLAG/FLAG-Ida и 35,3 % (6/17) (29,4 % — I–II степени, 5,9 % — IV степени) в группе ГО + азацитидин. В группе ГО + FLAG/FLAG-Ida 5 (33,3 %) пациентов имели серьезные нежелательные явления (СНЯ) в виде сепсиса. В группе ГО + азацитидин СНЯ отмечались у 6 (35,3 %) пациентов: 4 (66,6 %) — сепсис, 1 (16,7 %) — острая сердечно-сосудистая недостаточность, 1 (16,7 %) — острая дыхательная недостаточность. Медиана (диапазон) длительности нейтропении IV степени тяжести составила 23 (10–39) дня, нейтропении III степени — 24 (11–38) дня, тромбоцитопении IV степени — 21 (11–41) день, III степени — 26 (16–45) дней, I–II степени — 25 (22–45) дней. Длительность тромбоцитопении была более продолжительной у пациентов, получавших ГО + FLAG/FLAG-Ida, однако статистически значимых различий не отмечено. Случаев веноокклюзионной болезни печени не зарегистрировано. Медиана общей выживаемости (ОВ) в целом по обеим группам (n = 32) составила 31,4 мес., безрецидивной (n = 21) — 13,3 мес. В группе пациентов с эффективным лечением медиана ОВ не достигнута. В группе без эффекта этот показатель составил 18 мес. (p = 0,0442). Заключение. Комбинации ГО с химиотерапией FLAG/FLAG-Ida или азацитидином оказались эффективными у пациентов с рецидивами и рефрактерным течением ОМЛ. Возможность достижения ремиссии не зависела от принадлежности к группе риска по ELN, пола, возраста, уровня экспрессии CD33, числа предшествующих линий терапии, количества рецидивов. Комбинация ГО + азацитидин оказалась эффективной, безопасной и вполне переносимой у пациентов, рефрактерных к предшествующей высокодозной химиотерапии, а также при отягощенном соматическом статусе по ECOG. Это позволило в последующем выполнить аллоТГСК у данной категории больных. Частота развития гематологической и негематологической токсичности, длительность восстановления показателей крови статистически значимо не различались в обеих группах. Тромбоцитопения была более продолжительной в группе ГО + FLAG/FLAG-Ida, что согласуется с литературными данными. Эффективное лечение на основе ГО при рецидивах и рефрактерном течении ОМЛ существенно улучшает показатели ОВ: при сроке наблюдения 36 мес. медиана не достигнута.

Myeloid sarcoma, also known as chloroma or granulocytic sarcoma, is a rare disease characterized by the proliferation of immature myeloid cells in extramedullary lesions. Chloroma is more commonly observed in patients with acute myeloid leukemias, other myeloproliferative neoplasms, or myelodysplastic syndrome. However, it can also manifest itself as solitary tumor. Sarcoma can develop in different organs and tissues, but most frequently it appears in lymph nodes, soft tissues, and bones. Myeloid sarcoma with primary gynecological lesion is very rarely mentioned. In literature cases of cervical lesions are described. The present article summarizes the literature data concerning different aspects of myeloid sarcoma diagnosis and treatment. The issue under discussion is the role of chemotherapy, radiotherapy, surgery, and bone marrow transplantation in the treatment of this malignant tumor. It appears that whatever the primary tumor localization, the best treatment options are chemotherapy and allogeneic bone marrow transplantation (allo-BMT). A promising trend is the use of novel targeted drugs improving outcomes of treatment. The article provides a case report of a female patient with cervical myeloid sarcoma and concomitant bone marrow involvement, as well as the description of clinical course, diagnosis, and treatment. The patient received chemotherapy with subsequent allo-BMT. The pre-transplant therapy enabled allo-BMT with the deepest response possible. The patient achieved PET-and MRD-negative complete remission of cervical myeloid sarcoma and bone marrow.

Background. FLT3 gene is an important prognostic molecular marker in acute myeloid leukemia (AML). However, the detection of FLT3 mutations presents a challenge. Aim. To compare techniques used for the detection of FLT3 mutations, and to develop a test-system based on polymerase chain reaction (PCR) for quick and reliable determination of FLT3 mutation status. Materials & Methods. Bone marrow samples obtained from AML patients were subjected to examination. To detect FLT3-ITD and FLT3-TKD mutations PCR was performed with subsequent agarose gel electrophoresis visualization. The results were verified by Sanger sequencing. The data obtained using our test-system were compared with widely applied commercial kit ‘FLT3 Mutation Assay for Gel Detection’ by Invivoscribe. Results. To determine the FLT3 mutation status a PCR test was developed. This technique was validated on 22 bone marrow samples obtained from AML patients. FLT3-ITD mutation was detected in 4 patients, 3 patients showed FLT3-TKD mutation. In 1 patient both mutations were identified. These results fully corresponded to the molecular genetic analysis of FLT3, performed by ‘FLT3 Mutation Assay for Gel Detection’. The chosen technique was validated using Sanger sequencing data analysis. Conclusion. The article offers the review of all existing FLT3 mutation screening techniques and describes the experience of developing the PCR test for FLT3-ITD and FLT3-TKD mutation detection. The chosen technique is affordable and easy to use compared with the others. This study can be used as a guide for both doctors and researchers.

Aim. To assess the efficacy of FLAG/FLAG-Ida regimen and to identify factors that influence remission, duration of disease-free survival (DFS) and overall survival (OS) of patients with relapsed/refractory acute myeloid leukemia (AML). Materials & Methods. The trial included 54 patients (28 men and 26 women), median age was 37 years (range 18–70 years). 27 (50 %) out of 54 patients had refractory AML and 27 (50 %) patients had relapsed AML. FLAG and FLAG-Ida regimens were administered as induction therapy. 37 (68.5 %) patients received bone marrow transplantation. Molecular genetic and cytogenetic examinations were performed prior to therapy and on the 28th day after the start of treatment. WT1 gene expression was evaluated on the 14th–16th day of treatment. Results. Complete remission (CR) was achieved in 42 (77.8 %) out of 54 patients. Refractoriness to therapy was observed in 9 (16.7 %) out of 54 patients, mortality was 5.5 % (3/54). Remission rate was higher in patients with relapsed AML compared with refractory AML: 85.2 % (23/27) and 70.4 % (19/27), respectively. On the 14th–16th day of treatment patients with blast cell count ≥ 10 % in bone marrow (BM) showed significantly lower CR rate (60 %) compared with the group of patients with < 10 % blast cells in BM (89.6 %; p = 0.024) and shorter DFS (median 7.6 vs. 17.6 months, respectively; p = 0.03). Median DFS in patients with WT1 expression reduction to < 1 log on the 14th–16th day was 5 vs. 18 months in patients without WT1 expression reduction (p = 0.01). DFS varied in groups of patients with blast cell count < 10 % in BM on the 14th–16th day of treatment based on the level of WT1 expression reduction (p = 0.04). MRD-negative patients (57.1 %) showed significantly longer DFS and OS compared with MRD-positive patients (median DFS was 17.6 vs. 5.2 months, respectively, p = 0.02; median OS was 19 vs. 6.9 months, p = 0.0002). Median DFS and OS were different only in ELN low- and high-risk groups (median not reached vs. 5.2 months, respectively, p = 0.039; median not reached vs. 10.2 months, p = 0.039). Conclusion. FLAG and FLAG-Ida are effective and safe regimens in the treatment of relapsed/refractory AML. Achieving remission depends on neither the risk group nor the time of relapse occurrence. The blast cell count in BM on the 14th–16th day of FLAG/FLAG-Ida treatment is a prognostic factor determining achievement and duration of remission. WT1 expression level in the early post-induction period is a sensitive DFS marker. MRD status and molecular genetic risk (ELN) group affiliation are essential prognostic factors determining DFS and OS.

Aim. To assess the efficacy of FLAG/FLAG-Ida regimen and to identify factors that influence remission, duration of disease-free survival (DFS) and overall survival (OS) of patients with relapsed/refractory acute myeloid leukemia (AML). Materials & Methods. The trial included 54 patients (28 men and 26 women), median age was 37 years (range 18-70 years). 27 (50 %) out of 54 patients had refractory AML and 27 (50 %) patients had relapsed AML. FLAG and FLAG-Ida regimens were administered as induction therapy. 37 (68.5 %) patients received bone marrow transplantation. Molecular genetic and cytogenetic examinations were performed prior to therapy and on the 28th day after the start of treatment. WT1 gene expression was evaluated on the 14th-16th day of treatment. Results. Complete remission (CR) was achieved in 42 (77.8 %) out of 54 patients. Refractoriness to therapy was observed in 9 (16.7 %) out of 54 patients, mortality was 5.5 % (3/54). Remission rate was higher in patients with relapsed AML compared with refractory AML: 85.2 % (23/27) and 70.4 % (19/27), respectively. On the 14th-16th day of treatment patients with blast cell count ≥ 10 % in bone marrow (BM) showed significantly lower CR rate (60 %) compared with the group of patients with < 10 % blast cells in BM (89.6 %; p = 0.024) and shorter DFS (median 7.6 vs. 17.6 months, respectively; p = 0.03). Median DFS in patients with WT1 expression reduction to < 1 log on the 14th-16th day was 5 vs. 18 months in patients without WT1 expression reduction (p = 0.01). DFS varied in groups of patients with blast cell count < 10 % in BM on the 14th-16th day of treatment based on the level of WT1 expression reduction (p = 0.04). MRD-negative patients (57.1 %) showed significantly longer DFS and OS compared with MRD-positive patients (median DFS was 17.6 vs. 5.2 months, respectively, p = 0.02; median OS was 19 vs. 6.9 months, p = 0.0002). Median DFS and OS were different only in ELN low- and high-risk groups (median not reached vs. 5.2 months, respectively, p = 0.039; median not reached vs. 10.2 months, p = 0.039). Conclusion. FLAG and FLAG-Ida are effective and safe regimens in the treatment of relapsed/refractory AML. Achieving remission depends on neither the risk group nor the time of relapse occurrence. The blast cell count in BM on the 14th-16th day of FLAG/FLAG-Ida treatment is a prognostic factor determining achievement and duration of remission. WT1 expression level in the early post-induction period is a sensitive DFS marker. MRD status and molecular genetic risk (ELN) group affiliation are essential prognostic factors determining DFS and OS.

Background. Haploidentical bone marrow transplantation (BMT) can be a reliable alternative if a fully matched donor is not available. The main challenges after BMT are a relapse of major disease, graft-versus-host disease (GVHD), and infections. Azacitidine possesses antileukemic effect together with immunomodulating properties and being administered soon after BMT can significantly improve the outcome. Aim. To study azacitidine effect on the outcome of haploidentical BMT in patients with acute myeloid leukemia (AML) in the early post-transplantation period. Materials & Methods. The trial included 18 AML patients who received haploidentical BMT at VA Almazov National Medical Research Center. In all patients MRD-negative remission was achieved on the 30th day after BMT. Azacitidine therapy was initiated not earlier than 2 months after BMT with a complete engraftment of transplant and no GVHD. Azacitidine 100 mg/day was administered on D1-D5 every 28 days within a year after BMT. When a molecular relapse was detected, donor lymphocytes were additionally infused during every other cycle of therapy. Results. Eleven patients received preventive azacitidine treatment, 7 patients were included in control group. Median onset of azacitidine treatment after haploidentical BMT was 4 months (range 2-10 months), median number of azacitidine courses was 3.5 (range 1-9). During azacitidine treatment acute GVHD was identified in 5 (45.4 %) patients. In 4 of them an exacerbation of earlier GVHD was detected (3 with cutaneous form and 1 with intestinal form), and only in 1 patient de novo acute intestinal GVHD was discovered. Conclusion. Azacitidine treatment of AML patients after haploidentical allo-BMT is safe and well tolerated. Preventive azacitidine treatment after haploidentical BMT improves overall survival of AML patients.