A Study of RC48-ADC Combined With JS001 for Advanced Extramammary Paget Disease of the Scrotum

The goal of this clinical trial is to learn if Disitamab Vedotin combined with Toripalimab works to treat advanced HER2-positive extramammary Paget disease of the scrotum. It will also learn about the safety of this combination. The main questions it aims to answer are: Does this combination reduce tumor volume and delay disease progression? What medical problems do participants have when receving this combination? Participants will: Intravenous using this combination every 3 weeks until disease progression or intolerable adverse reactions occur. Visit the clinic once every 3 weeks for checkups and tests.