Assessing post-transplant minimal residual disease (MRD) can identify impending relapse in pediatric ALL patients who may therefore benefit from pre-emptive therapies, according to a prospective study of 115 patients. Fifty-four patients were younger than 10 and 61 patients were older than 10 years at the time of transplant. Researchers in the study assessed MRD using quantitative real-time PCR in patient bone marrow on days +30, +60, +100, +200, and +365 post-transplant. Three-year event-free survival (EFS) of the entire cohort was 52%. Three-year EFS of patients with negative MRD, MRD <10-3, and MRD ≥10-3 leukemic cells were 65%, 36%, and 0%, respectively (p<0.05). MRD also predicted cumulative incidence of relapse at three years, with rates of 23%, 75%, and 100%, respectively (p<0.05). The researchers concluded that post-transplant MRD assessment correlates with survival and allows the identification of patients with impending relapse.
Bader P, et al. Biol Blood Marrow Transplant (Full abstract only available to BBMT subscribers)