High-risk chronic lymphocytic leukemia: history, definition, diagnosis, and management

High-risk chronic lymphocytic leukemia is an emerging concept that was first established in fludarabine era. While fludarabine and fludarabine-containing regimens are highly effective in the majority of patients, a small subgroup of patients show poor response to standard regimens. The prognosis of these patients is dismal with a median overal survival of 2 – 3 years. The article present historical review and modern definition of high risk CLL, describes known molecular mechanisms of refractoriness to fludarabine and focuses on different treatment approaches.

• E.A. Nikitin FSBI «Haematological Research Center» Russian Ministry of Health, Moscow, Russian Federation ; Федеральное государственное бюджетное учреждение «Гематологический научный центр Министерства здравоохранения Российской Федерации», Москва, Российская Федерация
• A.B. Sudarikov FSBI «Haematological Research Center» Russian Ministry of Health, Moscow, Russian Federation ; Федеральное государственное бюджетное учреждение «Гематологический научный центр Министерства здравоохранения Российской Федерации», Москва, Российская Федерация

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