THE EFFECT ON THE COMPUTATIONAL ABILITY OF CHILDREN WITH ACUTE LYMPHOCYTIC LEUKEMIA DUE TO PROPHYLACTIC TREATMENT OF THE CENTRAL NERVOUS SYSTEM

Children diagnosed ten years ago as having acute lymphocytic leukemia had little chance of survival. Major advances have been made in the treatment of leukemia, but complications of the therapy are significant. With the introduction of prophylactic treatment of the central nervous system (CNS) to destroy leukemia cells in the cerebro-spinal fluid, the survival rate has dramatically increased. This treatment can lead to neurotoxicity which can impair intellectual functioning. Several researchers suggest this impairment is selective as to the abilities affected and that quantitative skills are affected the most. This research attempts to further delineate this issue. This research was conducted at the National Institutes of Health, Pediatric Oncology Branch, Bethesda, Maryland. It was based on earlier findings that acute lymphocytic leukemia patients who were treated with radiation to the brain and intrathecal methotrexate had lower intelligence scores than their healthy siblings. That study linked age at diagnosis to the amount of decrement in IQ. In this study the Stanford Diagnostic Mathematics Test, Computation Subtest, Blue Level, Form A, was given to 17 patients to assess their computational abilities. Those results were compared with results of computerized axial tomography scans (CAT) and scores on the Weschler Intelligence Scale for Children-Revised. An analysis was done on the effects of age at diagnosis, age at testing, and the difference in those two ages on the scores on the math test. It was concluded that the younger a child was at diagnosis the lower the math score. The age at testing was not significantly related to the math score. The difference between age at diagnosis and age at testing was related to the math score. This result suggests the possibility of progressive deterioration resulting from the CNS treatment. This research also observed a coincidence of abnormal CAT scans and the decrease in computational ability and highlights, for this specific skill, the relationship between age at diagnosis and impairment.