Detection of a dormant 20q- leukemia clone in bone marrow cultures with hematopoietic growth factors: implications for secondary leukemia post-transplant.

A patient developed secondary acute myelogenous leukemia with a 20q- marker chromosome abnormality six years following chemotherapy and radiation for Hodgkins disease (HD). Routine cytogenetics on the bone marrow which had been harvested and cryopreserved immediately following completion of initial therapy for HD showed no cytogenetic abnormality. However, a 20q- clonal marker was detected after culturing bone marrow with hematopoietic growth factors (HGF). The marrow was used successfully for an autotransplant. Post-transplant, the 20q- marker was again detected in HGF cultured samples. The patient relapsed at 165 days post-transplant with the 20q- marker and trisomy 21. These data suggest that standard cytogenetic assays may not detect abnormal clones which can cause leukemia post-transplant.