44 yrs female: lymph node biopsy. CLIN DGN. IV stage NHL.  
HISTO: There are bright irregular nodules, darker serpentines between and bright sinus zone. The cells: medium sized with cc like nuclei.  
IH: There is CD21 disrupted network in the nodules, small nodular proliferations and diffuse sinus proliferation. CD10+ cells in the periphery of the nodules, associated with Ki67+ activity. All populations Bcl2+ and the nodules are a little bit brighter. The sinus cells Mum1+ CD10-. The similar clear cell population invades the centers of follicles/nodules. CyclinD1 is completelly (-).  
BM: There is nodular and linear peritrabecular infiltration of CD20+CD10+ cells with oval and cleaved nuclei.  
DIAGNOSIS: FL with marginal differentiation vs ...?  
Thank you in advance. A lot of appologies for photos from a little bit different sites- L/N was small enough and the sections were slightly of different appearance.  
Special quest: MUM1+ some FL cells or totally marginal cells?