Abstract
Castleman disease (CD) is a group of lymphoproliferative disorders that share common histopathological features yet have widely different aetiologies, clinical features and grades of severity as well as treatments and outcomes. Siltuximab is currently the only therapy approved by the FDA and EMA for idiopathic multicentric CD and is recommended as first-line therapy in treatment guidelines. Despite the extensive characterization of siltuximab treatment in clinical trials, available evidence from real-world practice is still scant. This collection of clinical experiences focuses on patients treated with siltuximab therapy, particularly regarding the idiopathic multicentric CD diagnostic work-up, and on treatment administration in patients with complex disease entering differential diagnosis with CD or concomitant diseases. Thus, these data help further characterize and improve the use of siltuximab in real practice in terms of effectiveness and safety of long-term administration as well as consequences of treatment interruption.