Prognostic significance of blasts in the cerebrospinal fluid without pleiocytosis or a traumatic lumbar puncture in children with acute lymphoblastic leukemia : Experience of the dutch childhood oncology group

Purpose To determine the significance of blasts in the CSF without pleiocytosis and a traumatic lumbar puncture in children with acute lymphoblastic leukemia (ALL). Patients and Methods We retrospectively studied a cohort of 526 patients treated in accordance with the virtually identical Dutch protocols ALL-7 and ALL-8 Patients were classified into five groups. CNS1, no blasts in the CSF cytospin; CNS2, blasts present in the cytospin, but leukocytes less than 5/μL; CNS3, blasts present and leukocytes more than 5/μL Patients with a traumatic lumbar puncture (TLP, > 10 erythrocytes/mL) were classified as TLP+ (blasts present in the cytospin) or TLP- (no blasts). Results Median duration of follow-up was 13.2 years (range, 6.9 to 15.5 years) Event-free survival (EFS) was 72 6% (SE, 2.5%) for CNS1 patients (n = 304), 70.3% (SE, 4.7%) for CNS2 patients (n = 111), and 66.7% (SE, 19%) for CNS3 patients (n = 10; no significant difference in EFS between the groups). EFS was 58% (SE, 7 6%) for TLP+ patients (n = 62) and 82% (SE, 5 2%) for TLP-patients (n = 39; P <.01) Cox regression analysis identified TLP+ status as an independent prognostic factor (risk ratio, 3.5, 95% Cl, 1.4 to 8 8, P =.007). Cumulative incidence of CNS relapses was 0.05 and 0 07 in CNS1 and CNS2 patients, respectively (not statistically significant). Conclusion In our experience, the presence of a low number of blasts in the CSF without pleiocytosis has no prognostic significance In contrast, a traumatic lumbar puncture with blasts in the CSF specimen is associated with an inferior outcome.