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Table 1 Clinical characteristics, diagnostic findings, management, and outcomes of ICI-related MG in the whole cohort (n = 65) and in the MD Anderson Cancer Center patients (n = 14)a

From: Immune checkpoint inhibitor related myasthenia gravis: single center experience and systematic review of the literature

VariableTotal Cohort (n = 65); n (%)MDACC (n = 14); n (%)
MGFA classification
 I8 (12)1 (7)
 II14 (22)5 (36)
 III8 (12)0
 IV4 (6)0
 V29 (45)7 (50)
Clinical presentation
 Ptosis49 (75)11 (79)
 Dyspnea40 (62)10 (71)
 Limb weakness36 (55)7 (50)
 Dysphagia31 (48)7 (50)
 Diplopia27 (42)4 (29)
 Neck weakness22 (34)5 (36)
 Myalgias13 (20)4 (29)
 Dysarthria8 (12)3 (21)
 Facial weakness8 (12)3 (21)
 Blurry vision7 (11)4 (29)
 Dysphonia7 (11)4 (29)
 Generalized weakness6 (9)2 (14)
 Nasal speech/weakness of the palatal muscles6 (9)1 (7)
 Incontinence2 (3)1 (7)
Diagnostic tools
 Auto antibody panel positive titers
  Anti-AChR37/56 (66)5/10 (50)
  Anti-Striated muscle12/18 (67)6/9 (67)
 Muscle enzymes elevation
  CPK41/49 (84)9/10 (90)
  Troponin13/14 (93)6/7 (86)
 Edrophonium test positive4/5 (80)b0
 Ice pack test positive2/4 (50)b0
 Electrodiagnostic studies (skeletal muscle EMG, RNS, NCS)
  MG16/37 (43)c3/9 (33)
  Myopathy6/37 (16)d2/9 (22)
  MG and myopathy6/37 (16)d4/9 (44)
  Polyneuropathy3/37 (8)0/9
  No pathologic findings6/37 (16)0/9
Treatment of MG
  Corticosteroids59/63e (94)13/13 (100)
  Acetylcholinesterase inhibitors32/63e (51)7/13 (54)
  IVIG30/63e (48)9/13 (69)
  Plasmapheresis28/63e (44)8/13 (62)
  Other IST (MMF, rituximab, infliximab or tacrolimus)10/63e (16)6/13 (46)
  IA1/63e (2)1/13 (8)
  ICI holding/discontinuation61/63e (97)12/13 (92)
MG outcome
  Complete resolution12/62e,f (19)6/13 (46)
  Improvement34/62e,f (55)5/13 (39)
  Deterioration16/62e,f (26)2/13 (15)
Death24 (37)5/14 (36)
  MG complications15 (23)g3/14 (21)
  Cancer progression4 (6)2/14 (14)
  Other comorbidities3 (5)h0
  Unspecified2 (3)0
  1. aAbbreviations: MDACC MD Anderson Cancer Center, MGFA Myasthenia Gravis Foundation of America, Anti-AChR Anti-Acetylcholine receptor, CPK creatine phosphokinase, EMG electromyography, RNS repetitive nerve stimulation, NCS nerve conduction study, MG myasthenia gravis, IVIG intravenous immunoglobulin, IST immunosuppressive therapy, MMF mycophenolic acid, IA immunoadsorption, ICI immune checkpoint inhibitor. Numbers are rounded to the nearest whole number
  2. bOne patient had a partially positive test result
  3. cThree patients also had findings suggestive of polyneuropathy
  4. dTwo patients also had findings suggestive of polyneuropathy
  5. eTwo patients with pre-existing MG did not develop a flare of their disease after ICI initiation and were excluded from the analysis
  6. fData were not reported for one patient
  7. gTwelve patients died from respiratory failure, one patient died from hospital acquired pneumonia following hospitalization and two others died from worsening general status from severe dysphagia
  8. hOne patient died following acute hypercapnic respiratory failure unrelated to MG according to the authors, one patient died from complications of a preexisting heart disease and one patient died from aspiration pneumonia 1 month after discharge