Pb1950: chronic lymphocytic leukemia (cll): real-world data from lebanon

Topic: 6. Chronic lymphocytic leukemia and related disorders - Clinical Background: CLL has been a dynamic field of clinical research in the past two decades, but real-world data research on the different aspects of this disease in the population of Lebanon is still lacking. Aims: This study aims to describe the characteristics and outcomes of patients with CLL in the Lebanese population. Methods: This is a retrospective multi-center study involving Lebanese patients diagnosed between January 2004 and June 2021. Data was last updated in December 2022. Inclusion criteria comprised all patients diagnosed with CLL evaluated in hematology clinic. Patent demographics, clinical presentation, clinical stage, and treatment plan were recorded at diagnosis where available. Asymptomatic patients were kept on observation. Treatment was initiated as per the International Workshop on Chronic Lymphocytic Leukemia criteria. The choice of treatment was at the discretion of the treating physician in consultation with the patient as per respective financial and supportive care status. The probability of survival was estimated using Kaplan-Meier analysis. The outcomes of patients lost to follow-up are unknown. Minimal residual disease data were unavailable in this cohort of patients. Results: 127 patients were diagnosed with CLL between January 2004 and June 2021. Median age was 66 years (range, 30-90) and 35% of patients were female. Disease characteristics are detailed in Table 1. The median time of follow-up for all patients was 41.6 months. The median time spent in active surveillance was 66.9 months. As per the International Workshop on Chronic Lymphocytic Leukemia criteria, treatment indications in evaluable patients were constitutional symptoms (9%), progressive bone marrow failure (60%), splenomegaly (8%), lymphadenopathy (23%), Lymphocytosis (4%), and autoimmune cytopenia (2%). In the 40 patients who received first line therapy, treatment was with the fludarabine, cyclophosphamide, rituximab (FCR) regimen in 38%, with the bendamustine, rituximab (BR) regimen in 33%, with Ibrutinib in 21%, with the rituximab, cyclophosphamide, vincristine, prednisone (R-CVP) regimen in 8%, with Obinutuzumab in 6%, with rituximab in 4%, and with chlorambucil in 2%, respectively. Median PFS1 for the whole treated group was 51.9 months. In the patients treated with FCR, BR, and ibrutinib, median PFS1 was 51.9 months, 45.8 months, and undefined, respectively. In the 19 patients who received second line therapy, treatment was with the FCR regimen in 26%, with the BR regimen in 32%, with Ibrutinib in 26%, with the R-CVP regimen in 11%, and with RICE + ibrutinib+ Venetoclax in 5%, respectively. In the 11 patients who received third line therapy, treatment was with BR in 27%, with Ibrutinib in 55%, with the R-CHOP in 9%, and with Obinutuzumab in 9%, respectively. In the whole cohort of patients, 5-year OS was 100%. In the cohort of treated patients, 5-year OS was 89%. Median OS in both groups was not reached. Summary/Conclusion: This the largest real-world data set of CLL from Lebanon to the best of our knowledge. CLL survival in Lebanon is in accordance with international standards in the literature.Keywords: Survival, Real world data, Chronic lymphocytic leukemia