E019 A case of RS3PE triggered by immune check point inhibitor

Abstract Background/Aims Immune checkpoint inhibitors (ICIs) are increasingly being used in oncology and there is growing evidence of rheumatological problems arising these group patients. ICIs have been approved for the treatment several cancers including non-small cell lung cancer, renal carcinoma, Hodgkin lymphoma other malignancies. Pembrolizumab, an anti-PD1, known to cause inflammatory arthritis some patients, we report a case relapsing-remitting synovitis with pedal oedema (RS3PE) patient cancer. Methods A 67-year-old lady was diagnosed adenocarcinoma her left pleural pulmonary metastasis. She commenced on carboplatin, pemetrexed pembrolizumab initially 4 cycles followed by maintenance therapy another 2 years. However, while therapy, she started develop intermittent pain swelling small joints hands feet. There marked pitting extending up knee along dorsum hand. had as well. Results The blood tests were negative rheumatoid factor, anti-CCP ANA. CRP markedly raised (120) from previous values since developing joint symptoms. kidney liver function within normal limits. CT chest, abdomen pelvis done which did not reveal any metastasis or progression At time review prednisolone 20mg once daily. Following this, resolve, advised taper steroids gradually. stopped few months later. resolved weeks starting inflammation settled after stopping treatment. Conclusion ICI has trigger arthropathy like RA. Psoriatic arthritis, undifferentiated monoarthritis oligoarthritis, RS3PE tenosynovitis also reported. Most published cases mild moderate severity often responding corticosteroids. Several patients treated traditional DMARDs biologics. syndrome could be part paraneoplastic process but onset symptoms rapid resolution indicates that this likely drug-induced adverse effect. Disclosure D. Ramachandran: None. W. Mushtaq: Makkuni: