[Clinical and molecular biological characterization of patients with accelerated chronic lymphocytic leukemia]

Objective: To investigate the clinical and molecular biological characteristics of patients with accelerated chronic lymphocytic leukemia (aCLL) . Methods: From January 2020 to October 2022, the data of 13 patients diagnosed with aCLL at The First Affiliated Hospital of Nanjing Medical University were retrospectively analyzed to explore the clinical and molecular biological characteristics of aCLL. Results: The median age of the patients was 54 (35-72) years. Prior to aCLL, five patients received no treatment for CLL/small lymphocytic lymphoma (SLL), while the other patients received treatment, predominantly with BTK inhibitors. The patients were diagnosed with aCLL through pathological confirmation upon disease progression. Six patients exhibited bulky disease (lesions with a maximum diameter ≥5 cm). Positron emission tomography (PET) -computed tomography (CT) images revealed metabolic heterogeneity, both between and within lesions, and the median maximum standardized uptake value (SUVmax) of the lesion with the most elevated metabolic activity was 6.96 (2.51-11.90). Patients with unmutated IGHV CLL accounted for 76.9% (10/13), and the most frequent genetic and molecular aberrations included +12 [3/7 (42.9% ) ], ATM mutation [6/12 (50% ) ], and NOTCH1 mutation [6/12 (50% ) ]. Twelve patients received subsequent treatment. The overall response rate was 91.7%, and the complete response rate was 58.3%. Five patients experienced disease progression, among which two patients developed Richter transformation. Patients with aCLL with KRAS mutation had worse progression-free survival (7.0 month vs 26.3 months, P=0.015) . Conclusion: Patients with aCLL exhibited a clinically aggressive course, often accompanied by unfavorable prognostic factors, including unmutated IGHV, +12, ATM mutation, and NOTCH1 mutation. Patients with CLL/SLL with clinical suspicion of disease progression, especially those with bulky disease and PET-CT SUVmax ≥5, should undergo biopsy at the site of highest metabolic uptake to establish a definitive pathological diagnosis.