Molecular Biological Detection of Minimal Residual Disease in Acute Lymphoblastic Leukemia

During the last two decades substantial improvement has been made in the treatment of children with acute lymphoblastic leukemia (ALL). Chemotherapy alone induces complete clinical and hematologic remission in almost every patient and achieves cure rates of 75% [1, 2]. Progress in the treatment of adult ALL patients is less pronounced with long-term remissions in about 30% of cases [3]. This inferior outcome is at least partly explained by differences in the incidence of biologically defined leukemia subentities between both age groups [4]. In particular, BCR-ABL-positive ALL, the most aggressive ALL subtype, is observed in a third of the adults, but only in 4% of childhood ALL [5]. One major challenge of today’s oncology is therefore to guarantee a timely diagnosis of prognostically relevant entities and to design more efficient treatment strategies for respective patients, the latter being undoubtedly the more difficult task.