A Comprehensive and Systematic Analysis of Minimal Residual Disease (MRD) Monitoring in Follicular Lymphoma: Results from the Fondazione Italiana Linfomi (FIL) FOLL12 Trial

Background. Immunochemotherapy is effective in follicular lymphoma (FL), but most patients (pts) eventually relapse. MRD analysis, based on the detection of Bcl-2/IGH rearrangement by highly sensitive PCR-based tools, is effective in identifying pts at risk of relapse [Ladetto Blood 2012; Pott EHA23]. However, several issues are still unresolved, including: i) which is the best tissue source and the most reliable technique; ii) which are the most predictive time points; iii) which is the role of disease kinetics during the long natural history of FL. The FIL FOLL12 prospective, phase III randomized clinical trial (EudraCT: 2012-003170-60) included a systematic MRD analysis on both peripheral blood (PB) and bone marrow (BM) taken at eight different pre-planned time points, by both nested and real time quantitative (RQ)-PCR. Therefore, it allows addressing these unresolved issues.