Hairy Cell Leukemia

However, interpretation of these findings is limited by the non-randomized design and differences in rituximab exposure between groups, which may have contributed to the observed outcomes and limited definitive conclusions. Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.

Case 1 was a 65-year-old woman diagnosed in 2017 with SMZL and treated with rituximab, cyclophosphamide, hydroxydaunorubicin (doxorubicin), oncovin (vincristine), and prednisone (or prednisolone) (R-CHOP), achieving complete remission, who presented nine years later with recurrent hyperlymphocytosis at 10.8 × 109/L with villous appearance, massive splenomegaly, and systemic symptoms...The patient was treated with rituximab-bendamustine and achieved complete remission...Rituximab monotherapy was followed by rapid improvement, with normalization of the lymphocyte count to 2.13 × 109/L and regression of splenomegaly from the first cycle. These observations highlight the importance of combining lymphocyte immunophenotyping and bone marrow aspiration in isolated splenomegaly with villous lymphocytes on blood smear to avoid underdiagnosis of this new histopathological entity and therefore guide therapeutic management in the absence of guidelines.

Treatment regimens included Cladribine alone or with Rituximab, yielding high response rates and minimal toxicity. In this multiethnic Middle Eastern and North African cohort, HCL predominantly affected middle-aged men and was often incidentally detected. Cladribine-based therapy achieved durable remissions with excellent survival, highlighting consistent efficacy across diverse populations.

Standard treatment with purine analogs (i.e. cladribine) induces long-term remissions, but up to 25% of patients relapse early...The functional importance of DUSP1 was corroborated by demonstrating that BMSC-induced protection from cell death could be overcome through DUSP1 inhibition. Our results might set the stage for future clinical testing of DUSP1 inhibition to eliminate minimal residual disease (MRD) and prevent disease relapse in HCL.

P1, N=18, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Jun 2025 --> Jun 2026

P2, N=15, Completed, Scripps Health | Active, not recruiting --> Completed | Trial completion date: Dec 2026 --> Apr 2026 | Trial primary completion date: Dec 2026 --> Apr 2026

This case suggests that the combination of cladribine and low-dose rituximab may be an effective therapeutic strategy for classical HCL with TP53 abnormality, enabling deep molecular response and reversal of associated bone marrow fibrosis. Further prospective studies are warranted to validate these findings.

Aberrant expression of CD5 and CD23 is extremely rare. We present a case of classical HCL expressing both markers, along with a brief review of the literature emphasizing the diagnostic complexities associated with such aberrancy.

P1/2, N=50, Recruiting, Universita' Degli Studi Di Perugia | Not yet recruiting --> Recruiting

P1/2, N=55, Completed, University of Chicago | Active, not recruiting --> Completed