Survival curves according to ZAP-70, CD38 expression, and sCD23 levels. (A) Kaplan-Meier plot comparing numbers of ZAP-70⁺ B-CLL cells with overall survival (OS). The difference between patients with ZAP-70 greater than 20% and patients with ZAP-70 lower than 20% was highly significant (P < .001). Black line indicates ZAP-70 < 20%; gray line, ZAP-70 > 20%. (B) CD38 expression lower than 30% identified patients with a longer OS (P < .001). Black line indicates CD38 < 30%; gray line, CD38 > 30%. Less significantly, a longer OS was found in patients with sCD23 levels lower than 70 U/mL (C) (P = .013). Black line indicates sCD23 < 70 U/mL; gray line, sCD23 > 70 U/mL.