Disclosures: Rachel L. Coggins, DO: Nothing to disclose

Case Description: All 6 patients had immunotherapy for metastatic melanoma initiated within 6 months to the time of presentation with inflammatory arthropathy. Immunotherapy agents included pembrolizumab, nivolumab, and dabrafenib/trametinib. All patients presented with unilateral or bilateral knee pain and swelling. Physical exam was notable for joint effusions and joint line tenderness. Aspiration of joint fluid noted inflammatory arthritis. Imaging noted degenerative changes and joint effusions. 2 patients were initially treated conservatively, but 5 of 6 patients eventually received intra-articular steroids.

Setting: Outpatient clinic at academic medical center.

Patient: 6 adults with malignant melanoma.

Assessment/Results: At follow-up visit or phone call, all 5 patients who received injections had improvement in symptoms after intra-articular corticosteroid injections (CSI). 3 patients were also on a course of oral steroids. 1 patient had worsening pain as oral prednisone was tapered. 1 patient did require additional steroid injections with eventual improvement in symptoms. Rheumatologic agents were not started due to the concern for immune suppression and risk of reactivation of malignancy. 1 patient stopped immunotherapy due to the severity of arthritis symptoms.

Discussion: Inflammatory arthritis appears to be an increasingly appreciated adverse effect of immunotherapy for malignant melanoma, appearing during or after treatment.

Conclusion: Immunotherapy-related inflammatory arthritis can be difficult to treat, as symptoms can be recurrent despite aggressive treatment and some patients experience such severe effects that immunotherapies are discontinued. Treatment often involves high-dose oral steroids as well as intra-articular steroid injections. There is a lack of literature discussing immunotherapy-related inflammatory arthritis, and more research needs to be done in this area to develop a treatment protocol for this adverse effect of immunotherapy.

Level of Evidence: Level V

« Back to AAPM&R Annual Assembly 2019

PM&R Meeting Abstracts - https://pmrjabstracts.org/abstract/immunotherapy-related-inflammatory-arthritis-in-adults-with-malignant-melanoma-a-case-series/