PFS of 106 CLL Binet stage A patients assigned to different prognostic subgroups (Kaplan-Meier plots). (A) 25 patients with smoldering CLL versus 81 with nonsmoldering CLL: median PFS, 42 versus 18 months (P < .001). (B) 79 patients with nonsmoldering CLL are further divided according to s-TK levels: 31 with high s-TK values (>7.0 U/L) versus 48 with low s-TK values (≤7.0 U/L) had a PFS of 8 versus 49 months (P < .001). (C) 81 patients with nonsmoldering CLL are further divided according to the presence or absence of lymphadenopathy: 42 with lymphadenopathy versus 39 without lymphadenopathy had a median PFS of 10 versus 38 months (P < .001). (D) 106 Binet stage A patients, now classified in 52 patients with Rai stage 0, 42 patients with Rai stage I to II and low s-TK values (≤7.0 U/L), and 25 patients with Rai stage I to II and high s-TK values (>7.0 U/L). Median PFS was 75 months for Rai stage 0 patients, 31 months for Rai stage I/II with low s-TK, and 9 months for Rai stage I/II with high s-TK (P < .001).