Detection of minimal residual leukemia by polymerase chain reactions.

Disease recurrence following successful remission induction by polychemotherapy or bone marrow transplantation represents a major clinical problem in the treatment of leukemia patients. Sensitive methods for the identification of neoplastic cells escaping therapeutic interventions and potentially causing relapse are important for the monitoring of therapeutic effectiveness. The in vitro amplification of genomic or complementary deoxyribonucleic acid (cDNA) target sequences by polymerase chain reaction [1] has opened new avenues toward the detection of minimal residual leukemic cells at frequencies of 1: 10000 to 1: 1 000000. In the following we will briefly summarize our recent experience with the application of polymerase chain reaction (PCR) strategies to patients with chronic myelocytic leukemia (CML) and acute lymphoblastic leukemia (ALL) in complete remission according to clinical and laboratory parameters.