CD274 and extramammary Paget disease: Humanized monoclonal antibodies targeting PD-1 and PD-L1 have demonstrated both safety and efficacy in treating a variety of cancers.5 We noticed several researchers have published case reports about the role of immune-checkpoint-inhibitors monotherapy in patients with EMPD.6-8 But the conclusions are conflicting and there is still a lack of clinical trials to provide higher-quality evidence.