Our findings align with the EuroFlow consortium, which examined pre-analytical variables on samples from patients with haematological malignancies and suggested that protocols may need adjustments based on sample type and markers analysed.28 Notably, we found that CLL antigen expression is better preserved at refrigerator temperatures than RT, which contrasts with previous reports.27 Among the assessed markers, CD23 and CD200 showed statistically significant expression changes over time, with better stability at refrigerated temperatures. This evidence concerns the gene CD200 and B-cell chronic lymphocytic leukemia.