LAUSR

statistically significant, possibly due to the low number of cases. On the other hand, discordant BM infiltration had no significant prognostic influence. Conclusions: High resolution MFC allowed the detection of small clonal populations in BM in a very high proportion of patients with newly diagnosed DLBCL. In most cases, infiltration was discordant with tumor histology and, apparently, had no prognostic relevance. MRD was not detected in any of the cases. We plan to correlate MFC findings with those of histology and PET, also centrally reviewed, as well as to perform molecular studies on lymph node and BM samples to assess their clonal relationship.