(1) EUSA Pharma (UK) Limited (" EUSA Pharma"), a global biopharmaceutical company focused on oncology and rare diseases, announced that the National Comprehensive Cancer Network (NCCN ) for B-Cell Lymphomas to include siltuximab (SYLVANT ) as the preferred primary treatment for patients with human immunodeficiency virus-negative [HIV(-)] and human herpesvirus 8-negative [HHV-8(-)] multicentric Castleman disease (MCD), also known as idiopathic multicentric Castleman disease (iMCD), regardless of histopathologic subtype. 1 Siltuximab is currently approved in more than 40 countries worldwide for the treatment of all histopathologic subtypes of iMCD, a rare, life-threatening and debilitating orphan condition of the lymph nodes and related tissues. 2,3 The update is based on a 2020 publication which demonstrated that there is insufficient evidence to guide treatment based solely on lymph node histopathologic subtype.