Table 2

Characteristics of musculoskeletal IRAEs, laboratory and imaging results

PatientPattern of arthritisPMR-like diseaseOther MS IRAEsLatency of MS IRAEs after ICI start (days)CRP at onset of MS IRAEs (mg/L)RF/anti-CCPANA/ENAHLA-B27Synovial fluid cell counts (cells/µL)Proof of MSI on imaging: US (1), PET-CT (2), CT (3), MRI (4)
1Oligo+ve−ve1749.9−ve /−ve−ve /−ve−ve12 3001
2Mono−ve−ve121≤5.0−ve /−ve1:100/ NDNDND3, 4
3Mono+veSicca2895.5−ve /−ve−ve / ND−veND1, 4
5Poly+ve−ve4838.6−ve /−ve1:3200/ −ve−veND1
6Oligo−ve−ve14338.2−ve /−ve1:1600/−veNDND1
7Oligo−veSicca4371.3−ve /−ve−ve / ND−ve26001
8Mono−ve−ve3121.2−ve /−ve1:800/−ve−veND2
9Mono−ve−ve716≤5.0−ve/−ve1:200/−ve−veND2, 3, 4
10Mono−ve−ve253≤5.0+ve/ ve1:100/ NDNDND1, 4
11Oligo−veMyositis76≤5.0−ve/−ve−ve / ND−ve20 0001, 2, 3
13Oligo−ve−ve11648+ve/−ve1:12800/ SSA−ve60001, 2, 3
14Mono+ve−ve394114+ve/−ve−ve /−ve−veND1
  • MRI (hyperintensity on STIR images and/or prominent contrast enhancement on postcontrast fat-suppressed T1-weighted images).

  • ANA, antinuclear autoantibodies; anti-CCP, anti-cyclic citrullinated peptide antibodies; CRP, C reactive protein; ENA, extractable nuclear antigens; ICI, immune checkpoint inhibitor; IRAEs, immune-related adverse events; HLA, human leukocyte antigen; MS, musculoskeletal; MSI, musculoskeletal inflammation; ND, not determined; PET-CT, positron emission tomography-CT; PMR , polymyalgia rheumatica with ultrasound features including bursitis or tenosynovitis of shouldersor hips typical for PMR; RF, rheumatoid factor; Sicca, proven by Saxon and Schirmer test; SSA, anti-Sjögren’s syndrome-related antigen antibodies; US, ultrasound (proof of synovitis: ≥ grade 2 grey scale or ≥ grade 1 power Doppler findings); +ve, if positive; −ve, if negative.