Patients older than 17 years of age, with no upper age limit with a de novo histological diagnosis of DLBCL, in stages I and II and without risk factors, will be included. All patients will have a baseline PET-CT and will undergo 3 cycles of R-CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone). A PET-CT will be performed on day 15-18 of the third cycle that will be centrally reviewed. Those patients with negative PET-CT (Deauville 1, 2 and 3) will receive an additional cycle of R-CHOP and will finish treatment. Patients who have PET-CT with a Deauville 4 score will complete a fourth cycle and then receive radiation therapy to the compromised site. Those patients with a Deauville score of 5 should receive rescue therapy, so they will be outside the protocol.~A standardized follow-up of the patients included with tomographic controls will be carried out, evaluating OS (overall survival) and PFS (progression-free survival) at 3 years as the main objectives.
Prospective, multicenter, phase IV study, of real-life evidence destined to evaluate the feasibility and efficacy of performing a treatment adapted to PET-CT in patients with stage I and II DLBCL, without poor prognostic factors.