Real-world treatment patterns and outcomes in chronic lymphocytic leukemia: a multicenter retrospective study in Greece

PURPOSE: This study aims to characterize treatment patterns for chronic lymphocytic leukemia (CLL) in real-world clinical practice across Greece focusing on both treatment-naïve and relapsed or refractory (R/R) disease. We evaluated therapeutic patterns and outcomes including overall survival (OS), time to next treatment or death (TTNT-D) and overall response rate (ORR) and documented the incidence of other malignancies of patients who initiated first-line treatment between 2010 and 2024. METHODS: This is a panhellenic multicenter retrospective study of patients diagnosed with CLL between 2010 and 2020 from 8 centers in Greece. RESULTS: Overall, 1318 patients were included in the study. Fludarabine, cyclophosphamide and rituximab (FCR) was the most common first-line regimen (21.6%), followed by chlorambucil plus rituximab (16.3%) and ibrutinib-based therapies (14%). In the R/R setting, ibrutinib and venetoclax-based treatments, became the predominant therapeutic choices after 2014, replacing chemoimmunotherapy. Shifts in treatment patterns before and after 2016 reflected the incorporation of targeted agents into routine clinical practice, with a marked decline in FCR use and increased adoption of targeted therapies. Median OS was 162 months from diagnosis and 105.2 months (95% CI: 90.3-116.3) from first treatment. In patients receiving ibrutinib as first-line therapy, mOS was not reached, and median TTNT-D was 67.3 months. Overall, 18 (1.4%) cases developed a second hematological malignancy and 59 (4.5%) were diagnosed with a solid tumor. The most common hematological malignancy was myelodysplastic neoplasms and the most common solid tumors included lung, skin, breast, colon and prostate cancers. CONCLUSION: The findings suggest a gradual shift in CLL treatment patterns in Greece, with targeted agents increasingly replacing traditional chemoimmunotherapy in recent years and showing favorable survival outcomes.