A case of ICIs-associated arthritis caused by Toripalimab initially presenting as oedema in both lower limbs

The use of immune checkpoint inhibitors (ICIs) has offered new hope for patients with malignant tumours; however, it is essential to acknowledge their potential toxic side effects. Among these, ICIs-associated arthritis (IA) is not uncommon but non-specific and lacks diagnostic criteria. In this case, a patient with advanced colon cancer developed IA following treatment with Toripalimab. Notably, the condition improved after the administration of steroids, and the tumour remains well-controlled. This case report significantly contributes to enhancing clinicians' understanding of IA.