Molecular relapses (minimum residual disease) can be detected using using qualatitive or quantative RT-PCR analysis to detect bcr-abl mRNA transcripts.
The level of bcr-abl transcript is monitored after transplant every 3 months from a peripheral blood specimen (20 mls EDTA blood).
Quantative RT-PCR is the most sensitive technique for detecting residual CML with a sensitivity of 1/105 to 1/106 cells. If done early (3 -5 months after transplant) this assay has a strong prognostic value - with a much greater risk of relapse if the bcr-abl transcript is detectable.
