Tertiary lymphoid structures associated with improved prognosis and reduced invasion in advanced extramammary Paget disease

We analysed the presence and significance of tertiary lymphoid structures (TLS), a known prognostic and predictive biomarker of response to immune checkpoint inhibitors, in advanced extramammary Paget disease (EMPD). Our findings showed that TLS are associated with a favourable prognosis and may play a role in inhibiting tumour invasion, indicating that EMPD is an immunologically active tumour. These results suggest that immune checkpoint inhibitors could be an effective treatment option for advanced EMPD. To our knowledge, this study is the first report on TLS in EMPD.