8  CNS Disease and Relapse in APL

9 CNS relapse in APL

• In the pre-arsenic era, the incidence of extramedullary relapse in APL approximately ranged from 3% to 5%, most commonly in the CNS
• A large, consecutive cohort of newly diagnosed APL patients treated at our center over a 13-year period.(Jiang et al. 2025)
• A total of 910 newly diagnosed APL patients were eligible during the study period.
• Intracranial hemorrhage before or during induction and FLT3-ITD mutation¹ status emerged as prominent risk factors for CNS relapse

Jiang, Bingqian, Hongyan Tong, Haitao Meng, et al. 2025. “Characteristics and Predictors of Central Nervous System Relapse in Newly Diagnosed Acute Promyelocytic Leukemia in the Era of Arsenic: A 13-Year Monocenter Cohort Study.” Blood Cancer Journal 15 (1). https://doi.org/10.1038/s41408-025-01247-3.

Tashiro, Haruko, Ryosuke Shirasaki, Yoko Oka, et al. 2011. “FLT3 Internal Tandem Duplication Is Associated with a High Relapse Rate and Central Nervous System Involvement in Acute Promyelocytic Leukemia Cases: Single Institutional Analysis.” European Journal of Haematology 86 (3): 272–73. https://doi.org/10.1111/j.1600-0609.2010.01559.x.

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1. Even this study (Tashiro et al. 2011)supports FLT3-ITD status as a predictor of CNS relapse