Features at presentation predict children with acute lymphoblastic leukemia at low risk for tumor lysis syndrome

BACKGROUND. Tumor lysis syndrome (TLS) is a well-recognized complication of acute lymphoblastic leukemia (ALL). The ability to predict children at differing risk of TLS would be an early step toward risk-based approaches. The objectives of the current study were 1) to describe the prevalence and predictors of TLS in childhood ALL and 2) to develop a sensitive prediction rule to identify patients at lower risk of TLS. METHODS. Health records of children aged <= 18 years who were diagnosed with ALL between 1998 and 2004 were reviewed. TLS was defined by the presence of >= 2 laboratory abnormalities occurring in the time frame of interest. Predictors of TLS were determined using univariate and multiple logistic regression analyses. RESULTS. Among 328 patients, 23% met criteria for TLS. Factors predictive of TLS were male sex (odds ratio [OR], 1.8; P = .041), age >= 10 years (OR, 4.5; P < .0001), splenomegaly (OR, 3.3; P < .0001), mediastinal mass (OR, 12.2; P < .0001), T-cell phenotype (OR, 8.2; P < .0001), central nervous system involvement (OR, 2.8; P = .026), lactate dehydrogenase >= 2000 U/L (OR, 7.6; P < .0001), and white blood count (WBC) >= 20 x 10(9)/L (OR, 4.7; P < .0001). Among variables that were available at presentation, multiple regression analysis identified age >= 10 years, splenomegaly, mediastinal mass, and initial WBC >= 20 x 10(9)/L as independent predictors of TLS. When all 4 of those predictors were absent at presentation (n = 114 patients), the negative predictive value of developing TLS was 97%, with a sensitivity of 95%. CONCLUSIONS. Clinical and laboratory features at the time of presentation identified a group of children with ALL at low risk for TLS that may benefit from a risk-stratified approach directed at reduced TLS monitoring and prophylaxis.