Risk factors in long-term sequelae of central nervous system prophylaxis in successfully treated children with acute lymphocytic leukemia

Abstract

Seventy-two successfully treated patients with acute lymphocytic leukemia, all in first complete remission and all off therapy, who had received CNS prophylaxis (radiotherapy, 2,400 rad, plus intrathecal methotrexate), were studied by computed tomography (CT) of the brain, EEGs, and neurologic evaluations 3 to 9 years after the end of prophylaxis. Thirty-five patients showed CT brain scan abnormalities: intracranial calcifications (twelve); widening of the subarachnoid spaces (eight); isolated dilatation of ventricular spaces (three) and with frontal periventricular hypodensity (two); dilatation of ventricular and subarachnoid spaces (nine); and a hypodense area (one). Only 17 patients showed aspecific EEG abnormalities which were never linked to CT scan findings. None of our patients presented major motor deficits at the neurologic examination. A stepwise logistic regression technique showed that age less than 5 years at the time of prophylaxis was the most important risk factor (p = 0.008) of CT brain scan abnormalities followed by neurets (p = 0.037) and sex (p = 0.10). Furthermore, the multivariate analysis pointed out that the interactions between these variables were not significant and the effects were only of the first order.