Impact of baseline clinical and laboratory features on the risk of thrombosis in children with acute lymphoblastic leukemia: A prospective evaluation.

BACKGROUND: Children with acute lymphoblastic leukemia (ALL) have increased risk of thromboembolism (TE). However, the predictors of ALL-associated TE are as yet uncertain. OBJECTIVE: This exploratory, prospective cohort study evaluated the effects of clinical (age, gender, ALL risk group) and laboratory variables (hematological parameters, ABO blood group, inherited and acquired prothrombotic defects [PDs]) at diagnosis on the development of symptomatic TE (sTE) in children (aged 1 to ≤18) treated on the Dana-Farber Cancer Institute ALL 05-001 study. PROCEDURES: Samples collected prior to the start of ALL therapy were evaluated for genetic and acquired PDs (proteins C and S, antithrombin, procoagulant factors VIII (FVIII:C), IX, XI and von Willebrand factor antigen levels, gene polymorphisms of factor V G1691A, prothrombin gene G20210A and methylene tetrahydrofolate reductase C677T, anticardiolipin antibodies, fasting lipoprotein(a), and homocysteine). RESULTS: Of 131 enrolled patients (mean age [range] 6.4 [1-17] years) 70 were male patients and 20 patients (15%) developed sTE. Acquired or inherited PD had no impact on the risk of sTE. Multivariable analyses identified older age (odds ratio [OR] 1.13; 95% confidence interval [CI]: 1.01, 1.26) and non-O blood group (OR 3.64, 95% CI: 1.06, 12.51) as independent predictors for development of sTE. Patients with circulating blasts had higher odds of developing sTE (OR 6.66; 95% CI: 0.82, 53.85). CONCLUSION: Older age, non-O blood group, and presence of circulating blasts, but not PDs, predicted the risk of sTE during ALL therapy. We recommend evaluation of these novel risk factors in the development of ALL-associated TE. If confirmed, these easily accessible variables at diagnosis can help develop a risk-prediction model for ALL-associated TE.

Health-related quality of life in long-term survivors of acute lymphoblastic leukemia in childhood and adolescence.

PURPOSE: Children with acute lymphoblastic leukemia (ALL), the commonest form of cancer in this age group, suffer considerable morbidity during treatment, with the majority returning to good health soon after therapy has been completed, as reflected in health-related quality of life (HRQL). However, survivors are at risk of many adverse health outcomes later, including obesity, measured by body mass index (BMI), that is compounded by limited physical activity. This study examined the HRQL of long-term survivors of ALL and its relationship to BMI and physical activity. METHODS: A cohort of 75 subjects who were more than 10 years from diagnosis was assessed for BMI (weight in kg/height in m2) and completed two questionnaires. HRQL was measured by the multi-attribute, preference-based Health Utilities Index (HUI) instrument HUI23S4.15Q designed for self-report, and physical activity was quantified by the Habitual Activity Estimation Scale. RESULTS: The mean utility scores for overall HRQL (HUI2 = 0.88, HUI3 = 0.83) were similar to those in the Canadian and US general population segments of equivalent age (HUI2 = 0.86, HUI3 = 0.85). However, the minimum scores (HUI2 = 0.23, HUI3 = -0.09) revealed a group of survivors with notable disabilities in the attributes of hearing, emotion, cognition, and pain. There were no statistically significant correlations between HRQL and BMI or between HRQL and physical activity, except for deafness and inactivity on weekdays. CONCLUSIONS: Overall, long-term survivors of ALL in childhood enjoy good HRQL but some experience appreciable disability, though this is not associated with BMI or, in the main, with physical activity.