ABSTRACT
The study was held to define the factors helping in prediction of CNS infiltration by leukemia [ALL], type and rate of relapse. Also studing clinical and laboratory diagnosis especially CSF analysis at the primary diagnosis. The study was done in pediatric oncology unit of Zagazig University Hospital on 24 cases of newly diagnosed ALL ranging from 1-14 years. Males were 16 cases and females were 8 cases with male to female ratio of 2: 1. L[1] represented 75% of cases, Patients were subjected to different tests e.g CBC with differential count, hemoglobin level and B[2] microglobulin, bone marrow aspiration, morphological and chemical tests. CNS relapses were 20.9% of cases, hematological relapses were 12.9% and testicular relapses were 4.2%. Serum B[2] microgIobulin, CSF B[2] microglobulin and CSF LDH are useful indicators for cytological diagnosis of CNS infiltration at time of presentation. Cases with elevated B[2] M and/or LDH levels at presentation should be subjected to intensive CNS prophylaxis and CSF monitoring and follow up for better diagnosis and prognosis