CXCL13 and B-cell chronic lymphocytic leukemia: When compared to individuals with low plasma concentrations of CXCL13, whose median TTFT was 24 months (95% CI, 0.5–43 months, n = 46, p < 0.0001), the median TTFT for CLL patients with high CXCL13 concentrations was 4 months (95% CI, 0–27 months, n = 45).