The spectrum of CNS relapse during treatment of acute lymphoblastic leukemia
Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer, it is a systemic disease that arise from several cooperative genetic mutations in a single B or T lymphoid progenitor, leading to altered blast cell proliferation , survival, and maturation, and eventually to the lethal accumulation of leukemic cells with the tendency for post-therapeutic recurrence in the central nervous system and causes Relapse of (ALL) which is the main cause of treatment failure It may occur at a single extra medullary site or concomitantly with marrow relapse.(M. & W., 2018) The treatment directed at the (CNS) was one of the major advances for improving survival of (ALL) during the last decades , It consists in the administration of intrathecal chemotherapy, high dose systemic chemotherapy and cranial radiotherapy.(F. & H., 1980)
During therapy for acute lymphoblastic leukemia (ALL), children with central nervous system (CNS) toxicity are at risk for treatment changes, long-term squeal, and evenhigher mortality a better understanding of CNS symptoms and their complications enhances the potential for their prevention and treatment ,despite all the advances in the treatment of childhood acute lymphoblastic leukemia, central nervous system relapse remains an important obstacle to curing these patients. The survival of children with acute lymphoblastic leukemia (ALL) has greatly improved in the last 40 years with rates of up to 80% among the main referral centers, Relapse of ALL is the main cause of treatment failure,It may occur at a single extra medullary site or concomitantly with marrow relapse . This study will analyze the incidence of central nervous system relapse and the risk factors for its occurrence in children with acute lymphoblastic leukemia .