Effects of serum ferritin and clinical characteristics on the prognosis of diffuse large B-cell lymphoma: a multi-center retrospective study of Huaihai Lymphoma Working Group

Objective To investigate the effect of serum ferritin and related clinical characteristics on the prognosis of patients with diffuse large B-cell lymphoma (DLBCL). Methods Data were collected from 202 patients who were originally diagnosed with DLBCL with exact serum ferritin values from seven medical centers from March 2015 to November 2020. The optimal cutoff values of ferritin, age and albumin were calculated by Max Stat statistics. Univariable and multivariable analyses were performed using the Cox proportional risk model to determine the variables affecting the survival outcome of patients with DLBCL and subgroup analysis was performed. Results Among the 202 newly diagnosed DLBCL patients, 105 (52%) were men and 97 (48%) were women. The median age was 58 years old, and 74 cases (36.6%) were at the Ann Arbor Ⅰ-Ⅱ stage. The median follow-up time was 36 months. According to Mann-Whitney U test, there were statistical differences in serum ferritin, age and albumin between the survival group and the death group (P<0.05). The optimal cut-off values of serum ferritin, age and albumin were 246 μg/L, 74 years and 38.5 g/L, respectively. Univariate and multivariate analysis showed that ferritin, age and Eastern Cooperative Oncology Group (ECOG) score exerted impacts on the prognosis of DLBCL. In the low-risk and low/medium-risk international prognostic index (IPI) groups, the overall survival (OS) was remarkably different between patients with ferritin <246 μg/L and ferritin≥246 μg/L (P<0.05), but no significant difference was found in the Bcl-2⁺, Bcl-6-group, IPI high-risk group and IPI high-risk group. Conclusions Serum ferritin is a poor prognostic factor in DLBCL patients and can assist to distinguish poor prognostic patients among those with low risk of IPI.