THU0567 POLYMYALGIA RHEUMATICA-LIKE SYNDROME FROM CHECKPOINT INHIBITOR THERAPY: CASE SERIES AND SYSTEMATIC REVIEW OF THE LITERATURE
Authors: cassandra calabrese, Laura Cappelli, Marie Kostine, Elizabeth Kirchner, Tawnie Braaten, Leonard Calabrese
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Checkpoint inhibitor therapy has caused a paradigm shift in the field of oncology, producing significant survival benefits in patients with an ever-growing list of malignancies, but their use is attended by a spectrum of immune related adverse events (irAEs). Many rheumatic irAEs have been described. A critical and presently unanswered question is what proportion of these rheumatic irAEs represent new appearances of classic rheumatic diseases or, alternatively, represent new clinical variants with potentially different pathogenesis, clinical course and treatment responsiveness. Little is known about the PMR-like entity that has been described in the setting of ICI therapy. <h3>Objectives</h3> To assess whether the polymyalgia rheumatica (PMR)-like syndrome reported as an irAE from checkpoint inhibitor therapy is consistent with the 2012 EULAR/ACR provisional criteria for PMR<sup>1</sup>. <h3>Methods</h3> The cases were derived from two sources. Group 1 represents reported cases from three contributing centers. Group 2 was derived from a systematic review of the literature searching for all cases reported as PMR or PMR-like illness associated with checkpoint inhibitor therapy. Cases were assessed for the quality of reporting and then analyzed to determine whether they fulfilled the 2012 EULAR/ACR provisional criteria for PMR. <h3>Results</h3> A total of 49 patients were included for analysis, including 9 cases from Cleveland Clinic (Table 1), 4 cases from Johns Hopkins University, and 7 cases from University Hospital of Bordeaux, in addition to the 29 separate cases found by systematic review. Among the entire group, 37 (75%) were designated "complete" indicating that they had sufficient data to reliably apply the 2012 EULAR/ACR criteria of which 28 (75%) cases fulfilled complete criteria for PMR. A number of cases also demonstrated some clinical features unusual for idiopathic PMR. <h3>Conclusion</h3> This study suggests a high proportion of reported cases of checkpoint inhibitor-related PMR fulfill preliminary criteria for PMR yet in one quarter clinical details were incomplete making verification problematic. Furthermore, in the absence of a gold standard for the diagnosis of PMR, the relationship of checkpoint inhibitor-related PMR to the idiopathic form remains unclear. <h3>References</h3> [1] Dasgupta B, Cimmino MA, Maradit-Kremers H, et al. 2012provisional classification criteria for polymyalgia rheumatic: a European League Against Rheumatism/American College of Rheumatology collaborative initiative. Ann Rheum Dis2012;71:484-492. <h3>Disclosure of Interests</h3> cassandra calabrese Speakers bureau: Regeneron/Sanofi, Laura Cappelli Grant/research support from: Bristol-Myers Squibb, Consultant for: Regeneron/Sanofi Genzyme, Marie Kostine: None declared, Elizabeth Kirchner Consultant for: Celgene, Horizon, Novartis, Regeneron, Speakers bureau: Merck and Sanofi, Tawnie Braaten Grant/research support from: supported by T32 grant and "research reported in this publication was supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health under Award Number T32AR048522. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.", Leonard Calabrese Consultant for: Bristol-Myers-Squibb, Genentech and Astra-Zeneca.