Yes, it's truly remarkable how the ICI's have the ability to cause adverse events in just about every system of the body, requiring the intervention of doctors from nearly all medical specialties.
Some occur after 1 dose. Some occur years later.
Nobody yet knows just how effective the ICI's can be in producing adverse outcomes.
Documented toxicities include (but are not limited to):-
Rash Pruritis Vitiligo Immunobullous skin lesions akin to dermatitis herpetiformis or bullous pemphigoid Keratinocyte alteration—Grover’s disease [27]/acantholytic dyskeratosis Immune-reaction mediated by alteration of melanocytes (regression of nevi, prurigo nodularis, tumoural melanosis and vitiligo). Thyroid dysfunction Hyperthyroidism Hypothyroidism Hypophysitis Diabetes mellitus De novo diabetes Hepatitis Gastrointestinal toxicity Diarrhoea Colitis Colon perforation Enterocolitis Dysphagia Epigastric pain Oesophageal ulcerations, Gastritis, Duodenitis Lymphocytic colitis Pancreatitis Small bowel enteritis Pneumonitis Grade 3 to 4 cough Grade 3 to 4 dyspnoea Neurological toxicity Polyneuropathy Facial nerve palsy, Demyelination Myasthenia gravis, Guillain Barré syndrome Posterior reversible leukoencephalopathy Transverse myelitis Enteric neuropathy Encephalitis Aseptic meningitis Cardiac toxicity Myocarditis Pericarditis Arrhythmias, Cardiomyopathy Impaired ventricular function Rheumatological toxicity (as you mentioned) Myalgia Arthralgia Vasculitis Polymyositis, Myositis Temporal arteritis Renal toxicity Grade 3 to 4 nephritis Acute kidney injury Acute tubulo-interstitial nephritis with lymphocytic infiltration Severe antineutrophil cytoplasmic antibody-associated rapid progressive glomerulonephritis Ocular toxicities Peripheral ulcerative keratitis Uveitis Vogt–Koyanagi–Harada syndrome Thyroid-associated orbitopathy and idiopathic orbital inflammation (sceritis, myositis, neuritis, dacryadenitis) Retinal and choroidal disease (choroidal neovascularisation and melanoma-associated retinopathy) Haematological toxicities Lethal aplastic anaemia Autoimmune haemolytic anaemia Immune thrombocytopenic purpura
New effects are being discovered all the time. Such as hyperprogression.
There have been a few isolated reports of actual treatment benefit to a minority. Though these benefits are normally shortlived. And I have not been able to verify these reports.
The list of toxicities is not meant to be exhaustive, as new ones are being discovered all the time. A very versatile treatment..
Strangely, some well-informed patients with advanced disease who wish to extend their survival, opt for best palliative care instead of ICI treatment.
"Management of Toxicities from Immunotherapy: ESMO Clinical Practice Guidelines"