Atypical chronic myeloid leukemia (aCML) is a rare MDS/MPN disease characterized by the absence of BCR::ABL1 rearrangement and well known typical mutations associated with myeloproliferative disorders. Mutational landscape associated with this disease was recently described with frequent involvement of SETBP1 and ETNK1 mutations. CCND2 mutations have not been frequently detected in MPN or MDS/MPN patients. We describe two cases of aCML with two CCND2 mutations in 280 and 281 codons which rapidly develop progressive characteristics, and we reviewed the literature about this unfavorable association, suggesting a role as a new possible marker of aggressive disease.

First-line purine nucleoside analogues (PNAs) in hairy cell leukaemia (HCL) allow deep and long-lasting responses. We retrospectively analysed 53 HCL patients treated frontline with cladribine and assessed for response at 2 and 6 months after treatment to evaluate the kinetics of response. The estimated median progression-free survival was significantly different according to the degree of residual HCL infiltrate detected by immunohistochemistry at the bone marrow biopsy at 2 months (<= 5% vs. >5%, 247 vs. 132 months, respectively, p = 0.033), but not at 6 months (p = 0.79). Our data suggest a favourable prognostic impact of early marrow HCL clearance in patients treated with cladribine.