bloodjourГематология и трансфузиологияRussian journal of hematology and transfusiology0234-57302411-3042ООО Издательский дом «Практика»10.35754/0234-5730-2026-71-2-238-250bloodjour-768Research ArticleКЛИНИЧЕСКИЕ НАБЛЮДЕНИЯCASE REPORTSОпухолевые заболевания системы крови при синдроме конституционального дефицита репарации ошибочно спаренных нуклеотидовHematological malignancies in constitutional mismatch repair deficiency syndromehttps://orcid.org/0009-0004-4226-6816ТихоноваЮ. А.TikhonovaYu. A.

Тихонова Юлиана Андреевна, ординатор

117997, г. Москва

Yuliana A. Tikhonova, Resident Physician

117997, Moscow

yuliana.tihonova123@gmail.comhttps://orcid.org/0009-0000-6734-0331КлюхинВ. В.KlyukhinV. V.

Клюхин Владислав Валерьевич, гематолог консультативного отделения

117997, г. Москва

Vladislav V. Klyukhin, Hematologist, Consultative Department

117997, Moscow

Nccxbak@mail.ruhttps://orcid.org/0000-0003-2801-7421ЕвстратовД. А.EvstratovD. A.

Евстратов Дмитрий Андреевич, кандидат медицинских наук, детский онколог отделения онкогематологии

117997, г. Москва

Dmitrii A. Evstratov, Cand. Sci. (Med.), Pediatric Oncologist, Department of Oncohematology

117997, Moscow

dmitriy.evstratov@dgoi.ruhttps://orcid.org/0000-0003-1216-817XКлиментоваМ. А.KlimentovaM. A.

Климентова Мария Алексеевна, гематолог отделения трансплантации гемопоэтических стволовых клеток № 1

117997, г. Москва

Maria A. Klimentova, Hematologist, Department of Hematopoietic Stem Cell Transplantation No. 1

117997, Moscow

maria.klimentova@dgoi.ruhttps://orcid.org/0000-0003-3007-3772ЯськоЛ. А.YaskoL. A.

Ясько Людмила Александровна, кандидат биологических наук, старший научный сотрудник лабораторий молекулярной онкологии и молекулярной биологии

117997, г. Москва

Ludmila A. Yasko, Cand. Sci. (Biol.), Senior Researcher, Laboratories of Molecular Oncology and Molecular Biology

117997, Moscow

liudmila.yasko@dgoi.ruhttps://orcid.org/0000-0002-4779-1896МяковаН. В.MyakovaN. V.

Мякова Наталия Валерьевна, доктор медицинских наук, профессор, заместитель главного врача по лечебной работе

117997, г. Москва

Natalia V. Myakova, Dr. Sci. (Med.), Professor, Deputy Chief Physician for Medical Affairs

117997, Moscow

Natalya.Myakova@dgoi.ruhttps://orcid.org/0000-0003-0900-6874КурниковаМ. А.KurnikovaM. A.

Курникова Мария Андреевна, кандидат медицинских наук, генетик, старший научный сотрудник лаборатории молекулярной биологии

117997, г. Москва

Maria A. Kurnikova, Cand. Sci. (Med.), Medical Geneticist, Senior Researcher, Laboratory of Molecular Biology

117997, Moscow

maria.kurnikova@dgoi.ruФГБУ «Национальный медицинский исследовательский центр детской гематологии, онкологии и иммунологии им. Дмитрия Рогачева» Министерства здравоохранения Российской ФедерацииРоссияDmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, Ministry of Healthcare of Russian FederationRussian Federation202617072026712238250Copyright © Тихонова Ю.А., Клюхин В.В., Евстратов Д.А., Климентова М.А., Ясько Л.А., Мякова Н.В., Курникова М.А., 20262026Тихонова Ю.А., Клюхин В.В., Евстратов Д.А., Климентова М.А., Ясько Л.А., Мякова Н.В., Курникова М.А.Tikhonova Y.A., Klyukhin V.V., Evstratov D.A., Klimentova M.A., Yasko L.A., Myakova N.V., Kurnikova M.A.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.htjournal.ru/jour/article/view/768Введение

Введение. Синдром конституционального дефицита (Constitutional mismatch repair defi ciency syndrome, CMMRD) представляет собой редкий аутосомно-рецессивный синдром предрасположенности к развитию злокачественных новообразований.

Цель

Цель: представить клиническое наблюдение больного с рецидивом Т-лимфобластной лимфомы, у которого был диагностирован наследственный синдром предрасположенности к опухолям (синдром конституционального дефицита репарации ошибочно спаренных нуклеотидов).

Основные сведения

Основные сведения. Причиной возникновения СMMRD считают наличие биаллельных герминальных гомо- или компаунд-гетерозиготных вариантов в генах системы MMR ( MLH1, MSH2, MSH6, PMS2 ), инактивация этих генов приводит к увеличению мутационной нагрузки и, как следствие, к злокачественной трансформации клеток. Утрата функции системы MMR обуславливает развитие широкого спектра злокачественных новообразований в детском и подростковом возрасте, при этом зачастую дебют первой неоплазии приходится на опухолевые заболевания системы крови. Отдаленный прогноз для больных с CMMRD остается крайне неблагоприятным в связи с высоким риском развития метахронных злокачественных новообразований других локализаций, что диктует необходимость систематического мониторинга данной группы больных.

Introduction

Introduction. Constitutional mismatch repair deficiency (CMMRD) syndrome is a rare childhood cancer predisposition syndrome.

Aim

Aim: to present a unique clinical case of a patient with relapsed T-lymphoblastic lymphoma who was diagnosed with a rare hereditary cancer predisposition syndrome (constitutional mismatch repair deficiency syndrome).

Main findings

Main findings. The cause of CMMRD is considered to be the presence of biallelic germline homo- or compound-heterozygous variants in one of the four MMR genes ( MLH1, MSH2, MSH6 or PMS2 ); inactivation of these genes leads to an increased mutational burden and, consequently, to malignant transformation of cells. Loss of MMR system function underlies the development of a broad spectrum of malignancies in children and adolescents, with the first neoplasm often presenting as a hematological malignancy. The long-term prognosis for patients with CMMRD remains extremely poor due to the high risk of developing metachronous malignancies of other localizations, which necessitates systematic surveillance of this patient group.

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The authors declare that there are no conflicts of interest present.