Pediatric Hematology/Oncology and ImmunopathologyPediatric Hematology/Oncology and ImmunopathologyВопросы гематологии/онкологии и иммунопатологии в педиатрии1726-17082414-9314Fund Doctors, Innovations, Science for Children69210.24287/1726-1708-2023-22-2-123-141CLINICAL OBSERVATIONSКЛИНИЧЕСКИЕ НАБЛЮДЕНИЯExtramedullary involvement in pediatric myeloid leukemia: challenges of diagnosis and treatment. Clinical cases and a literature reviewЭкстрамедуллярные поражения при остром миелобластном лейкозе у детей: особенности диагностики и лечения. Клинические примеры и обзор литературыhttps://orcid.org/0000-0002-2003-0982DinikinaYu. V.ДиникинаЮ. В.
Russian Federation

Yulia V. Dinikina, Cand. Med. Sci., Head of the Department

Department of Chemotherapy for Hematologic Diseases and Bone Marrow Transplantation for Children

197341

2 Akkuratova St.

St. Petersburg

Юлия Валерьевна Диникина, канд. мед. наук, заведующая отделением

отделение химиотерапии онкогематологических заболеваний и трансплантации костного мозга для детей

197341

ул. Аккуратова, 2

Санкт-Петербург

dinikina_yuv@almazovcentre.ruhttps://orcid.org/0000-0002-0016-6698MaschanA. A.МасчанА. А.
Russian Federation

Moscow

Москва

The Almazov National Medical Research Centre, Ministry of Healthcare of the Russian FederationФГБУ «Национальный медицинский исследовательский центр им. В.А. Алмазова» Минздрава РоссииThe Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, Ministry of Healthсare of the Russian FederationФГБУ «Национальный медицинский исследовательский центр детской гематологии, онкологии и иммунологии им. Дмитрия Рогачева» Минздрава России080720232221231412202202327032023Copyright ©; 2025, «D. Rogachev NMRCPHOI»Copyright ©; 2025, ФГБУ «НМИЦ ДГОИ им. Дмитрия Рогачева» Минздрава России2025«D. Rogachev NMRCPHOI»ФГБУ «НМИЦ ДГОИ им. Дмитрия Рогачева» Минздрава Россииhttps://creativecommons.org/licenses/by/4.0https://hemoncim.com/jour/article/view/692

   The problem of extramedullary (EM) involvement in acute myeloid leukemia (AML) in children is of considerable relevance since its pathogenesis remains understudied and the impact on prognosis is still unclear. The variability of tissue and organ involvement depends on immunophenotypic, cytogenetic, and molecular features of myeloid cells and can cause difficulties in diagnosis, thus making it necessary to combine imaging and laboratory tools for timely and accurate diagnosis of EM disease. The prognostic significance of EM involvement has not been established unequivocally, thus the need for intensification of chemotherapy, as well as for allogeneic hematopoietic stem cell transplantation in first remission, remain debatable. The results of target therapy in EM AML are encouraging and may reduce the risk of AML relapse. This article describes the clinical features of EM AML in children and reviews the diagnostic approaches as well as the advantages and limitations of existing laboratory and imaging methods. The molecular features of EM AML, current treatment options and prognosis have also been analyzed. The patients' parents gave their consent to the use of their children's data, including photographs, for research purposes and in publications.

   Проблема экстрамедуллярных поражений (ЭМП) при остром миелобластном лейкозе (ОМЛ) у детей сохраняет высокую актуальность, поскольку их патогенез остается малоизученным, а влияние на прогноз однозначно не определено. Вариабельность вовлечения тканей и органов при ЭМП зависит от иммунофенотипических, цитогенетических и молекулярно-генетических особенностей лейкемических клеток, обусловливает трудности диагностики и определяет необходимость использования комбинации методов визуализации и лабораторных исследований в целях своевременной и адекватной детекции ЭМП. Наличие ЭМП не является однозначным критерием высокого риска ОМЛ, в связи с чем необходимость интенсификации химиотерапии, а также проведения аллогенной трансплантации гемопоэтических стволовых клеток в первой ремиссии остается дискутабельной. Результаты использования таргетной терапии в отношении ЭМП при ОМЛ представляются обнадеживающими и могут снизить вероятность рецидива ОМЛ. В статье описаны особенности клинического течения ОМЛ у детей с ЭМП, подходы к диагностике заболевания с определением преимуществ и ограничений существующих лабораторных исследований и методов визуализации. Проанализированы молекулярно-генетические особенности экстрамедуллярных форм ОМЛ, существующие опции терапии и прогноз. Родители пациентов дали согласие на использование информации, в том числе фотографий детей, в научных исследованиях и публикациях.

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