Clinical characteristics and prognostic factors of lymphoma patients initially presenting with fever of unknown origin

Background: Lymphoma has been identified as the most common cause of non-infectious fever of unknown origin (FUO). However, clinical characteristics and prognostic factors in lymphoma patients with FUO are lacking. Methods: From January 1, 2013 to December 31, 2019, our center enrolled 185 patients who initially presented with FUO but were later diagnosed with lymphoma in Huadong Hospital of Fudan University. The FUO and matched non-FUO groups were compared in terms of clinical symptoms, laboratory examinations, overall survival (OS), and progression-free survival (PFS). The prognostic factors of OS and PFS in patients with FUO were assessed by Cox analyses. Results: In the FUO group (180 in total), B cell non-Hodgkin's lymphoma (B-NHL) cases were 88 (48.9%), T cell non-Hodgkin's lymphoma (T-NHL) was 60 (33.3%), NK/T cell lymphoma (NK/T-CL) was 24 (13.3%), and Hodgkin's lymphoma (HL) was 8 (4.4%). During the hospitalization, the maximum body temperature of the FUO group diagnosed with B-NHL, T-NHL, or NK/T-CL was statistically higher than that of the non-FUO group (P < 0.05). The differences in OS between the FUO and non-FUO groups were significant for HL (P = 0.006), B-NHL (P = 0.007), and T-NHL (P = 0.013). In the multivariate analyses, the log(10) serum ferritin was an independent risk factor for all-cause death in patients with FUO (hazard ratio, 9.578; 95% confidence interval, 1.382-66.365; P = 0.022). Conclusion: We found that the subtypes of lymphoma initially presenting with FUO were mostly B-NHL and T-NHL. The detection of ferritin levels during the hospital stay may help predict the long-term survival rate in patients with FUO.