For example, some spindle brain aneurysms are caused by mutations in PDGFRB.[11] Some studies have compared the frequency of PDGFRB mutations in different cancers and found that the incidence of PDGFRB mutations was the highest in single-center Castleman disease.[12] At present, PDGFRB is often fused with other genes for the study of some cancers, especially leukemia. Here, PDGFRB is linked to Castleman disease.