Diagnosis and Treatment of Rheumatic Adverse Events Related to Immune Checkpoint Inhibitors

Table 4

Management of immunotherapy-related myositis.

Level	Description	NCCN guideline	CSCO guideline
G1	Mild symptoms with or without pain	Consider stopping ICIs; consider PMR/GCA (see Table 3 for treatment principle); continuous monitoring of aldolase and creatine kinase; if indicated, treat pain (e.g., NSAIDs).	Continue ICIs; overall evaluation of patients’ muscle strength; creatine kinase, aldolase, transaminase (AST, ALT), and lactate dehydrogenase (LDH) were monitored; if the level of creatine kinase increases and the muscle strength decreases, glucocorticoid can be given; after eliminating the related contraindications, acetaminophen or NSAIDs can be given for pain relief.
G2	Moderate symptoms with or without pain, affecting instrumental ADL	If the level rises, stop ICIs; muscle MRI and EMG were performed; prednisone 1-2 mg/kg/D; consider muscle biopsy, especially in severe or refractory cases; aldolase and creatine kinase were monitored continuously until symptoms disappeared or steroids were stopped.	ICI was suspended until the related symptoms were controlled, creatine kinase returned to the normal level, and prednisone dosage was less than 10 mg; NSAIDs can be given to relieve pain after removing related taboos; if creatine times of the upper limit of the normal value, prednisone (or equivalent dose of other drugs) was given for treatment.
G3	Severe symptoms with or without pain, affecting self-care ADL	If there are indications, treat the pain; please consult with the rheumatology department or neurology department; intravenous immunoglobulin (IVIG), 2G/kg, should be used for administration according to the instructions; if steroid is difficult to treat, plasma exchange may be considered and infliximab or mycophenolate mofetil may be given.	Suspend ICIs until G1; consider admission; please consult with the rheumatology department or neurology department; use 1 mg/kg/D methylprednisolone (or equivalent dose of other drugs); IVIG and plasma exchange were considered.