The prognostic value of PET/CT evaluation with Deauville score on the recurrence and survival in diffuse large B-cell lymphoma: a multi-institutional study of KROG 17-02.

The Korean Radiation Oncology Group (KROG) assessed the value of Deauville score (DS) on 18F-fluorodeoxyglucose Positron emission tomography-computed tomography (FDG PET/CT) as a predictor of recurrence and survival after rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy in diffuse large B-cell lymphoma (DLBCL). A total of 512 patients with stage I-III DLBCL who received six cycles of R-CHOP with or without radiation therapy (RT) and obtained treatment responses according to PET-CT imagings after R-CHOP ± RT were included. Patients were sorted into two arms; DS 4-5 arm (n = 24) was matched at a 1:2 ratio with DS 1-3 arm (n = 48) using propensity score matching method. After a median follow-up time of 37.2 months, the recurrence-free survival rate (86.6% vs. 66.8%, P = 0.041) and overall survival rate (86.9% vs. 62.2%, P = 0.009) at 5 years were significantly different between the DS 1-3 and DS 4-5 arms. DS 4-5 arm showed higher 5-years locoregional recurrence-free survival (88.8% vs. 74.3%, P = 0.155) and distant failure-free survival (91.1% vs. 84.3%, P = 0.333) than DS 1-3 arm. In the multivariate analysis, DS was still a significant factor for recurrence-free survival [hazard ratio (HR), 3.840 and confidence interval (CI), 1.068-13.806; P = 0.039] and overall survival rates (HR 4.453 and CI 1.274-15.562; P = 0.019). This study showed and validated that Deauville score of 4-5 of PET-CT imaging taken after full-course of R-CHOP chemotherapy with or without RT could predict recurrence-free survival and overall survival in DLBCL patients.