Worsening and newly diagnosed paraneoplastic syndromes following anti-PD-1 or anti-PD-L1 immunotherapies, a descriptive study

Our results show that PNSs tend to be worsened or revealed by anti-PD-1 or anti-PD-L1 immunotherapy. Cases of paraneoplastic encephalitis are of notable concern, in view of their severity. When initiating immunotherapy, physicians should carefully monitor patients with a pre-existing PNS.