Does MRD have a role in the management of iNHL ?

Among indolent non- Hodgkin lymphomas (iNHLs), the analy sis of measur able / minimal residual disease (MRD) has been exten sively applied to fol lic u lar lym phoma (FL). Treatment com bi na tions have deeply changed over the years, as well as the tech niques to mea sure MRD, which is cur rently eval u ated only in the set ting of clin i cal tri als. Here, we dis cuss the evidence on the role of molec u lar mon i tor ing in the man age ment of FL. Mature data sup port the quan ti fi ca tion of molec u lar tumor bur den at diag no sis as a tool to strat ify patients in risk categories and of MRD eval u a tion at the end of treat ment to pre dict pro gres sion - free sur vival and over all sur vival. Moreover, MRD deserves fur ther stud ies as a tool to refi ne the clinical/ metabolic response and to modulate treatment intensity / duration. Patients with a higher relapse probability can be identifi ed, but the rele vance of continuous molecular follow - up should be clarifi ed by kinetic models of MRD analy sis. Being the BCL2 / heavy chain immu no glob u lin gene hybrid rearrangement detect able in about 50 % to 60 % of advanced FL and in 30% of positron emission tomography / computed tomography - staged localized FL, technical advancements such as next - gener ation sequencing/ tar get locus amplifi cation may allow broadening the FL population carrying a molecular marker. Droplet dig i tal poly mer ase chain reac tion can bet ter quan tify MRD at low lev els, and novel sources of DNA, such as cell - free DNA, may rep re sent a non in va sive tool to mon i tor MRD. Finally, MRD in other iNHLs, such as lymphoplasmacytic lymphoma/ Waldenstr öm macroglobulinemia and mar ginal zone lymphoma, is beginning to be explored.