[Long-term monitoring of therapy-induced computerized tomographic cranial changes in children with acute lymphoblastic leukemia].

Purpose: Long-term follow-up of cranial CT scans of children with acute lymphoblastic leukemia and evaluation of the influence of chemo- and radiotherapy on the CCT changes.

Patients And Methods: CCT scans of 68 children with non-B-ALL were analyzed retrospectively for signs of atrophy and changes in density. Patients were treated between 1981 and 1990 at the St. Anna Childrens Hospital Vienna according to the ALL-BFM protocols. Children were examined with CCT in defined periods from diagnosis until 3 years after cessation of treatment. As a control group served 69 patients with solid tumors who had not received corticoids or cranial irradiation.

Results: At the initial examination 56% of the ALL-patients showed CCT changes, 85% of these patients had already received corticoids. In the control group only 20% of the CCTs were found abnormal (p = 0.005). In both groups an age-dependence was found: 64% of the ALL-patients under five years of age and 22% of the patients above 5 years had initial CCT changes (p = 0.001). In the control group 39% of the patients under five years of age and 7% of the older patients showed CCT changes at the beginning of treatment (p = 0.003). The highest incidence of abnormal CCT scans (68%) was seen during intensive chemo- and radiotherapy. Until the end of therapy the incidence of abnormal CCTs decreased to 32%. After cessation of antileukemic therapy 35% of the patients whose CNS-prophylaxis included cranial irradiation, and 12% of the non-irradiated patients had abnormal CCT scans.

Conclusion: Corticoids can cause reversible signs of cerebral atrophy. In the assessment of CCTs a physiological age-dependence of the volume of the CSF compartment has to be taken into consideration. The main reason for non-reversible CCT changes is the CNS- prophylaxis, above all the cranial irradiation, whereby younger children seem to be particular vulnerable.