Polymerase chain reaction: a method for monitoring tumor cell purge by long-term culture in BCR/ABL positive acute lymphoblastic leukemia.

We report the successful purging of leukemia cells bearing the Philadelphia chromosome and BCR/ABL transcripts by long-term marrow culture (LTC), and subsequent grafting of the purged marrow in a case of refractory acute lymphoblastic leukemia. The efficiency of the purge was evaluated by polymerase chain reaction (PCR) for BCR/ABL transcripts. In two LTCs initiated in the blastic stage, we demonstrated the selective effect of three culture media (serum dependent, serum-free (SF) supplemented or not with IL3 and GM-CSF) on the proliferative potential of normal hematopoietic (CFU-GM/BFU-E) and leukemic progenitors (CFU-ALL)