IR-pulmonary toxicities are a group of heterogeneous diseases including different clinical entities such as the frequent IR-interstitial lung disease (IR-ILD) or IRpneumonitis and other rare entities such as IRbronchiolitis or IR-lung sarcoidosis.

In general, symptoms include dyspnoea, cough, chest pain, fever and hypoxia.

Radiological patterns of IR-ILD have been classified into five possible subtypes: cryptogenic organising pneumonia-like, groundglass opacities, interstitial, hypersensitivity and pneumonitis not otherwise specified.

Several histopathological findings have been reported for IRILD, including cellular interstitial pneumonitis, organising pneumonia and diffuse alveolar damage, while sometimes only minimal abnormalities can be identified. Nevertheless, it is important that any pathognomonic radiological or pathological features are clearly identified.

Purple: general categories or stratification; turquoise: combination of treatments or other systemic treatments; white: other aspects of management.

ARDS, acute respiratory distress syndrome; BAL, bronchoalveolar lavage; b.i.d., twice daily; Ca, calcium; CBC, complete blood count; CRP, C-reactive protein; CS,

corticosteroid; CT, computed tomography; ESR, erythrocyte sedimentation rate; ICI, immune checkpoint inhibitor; ILD, interstitial lung disease; IR, immune-related; i.v.,

intravenous; IVIG, intravenous immunoglobulin; LFT, liver function test; MMF, mycophenolate mofetil; M/W/F, Monday,Wednesday and Friday; TLCO, transfer capacity

of the lung for carbon monoxide; TFT, thyroid function test; UEC, urea and electrolytes.

• Dyspnoea should trigger a full clinical work-up, including the exclusion of infectious pneumonia, tumour progression, pulmonary embolism, cardiac events (including heart failure, myocarditis, acute myocardial infarction and arrhythmias) and pleural carcinomatosis or effusion
• Patient cases with pre-existing ILD should be discussed with a specialist before initiation of ICI
• If IR-ILD is suspected, a high-resolution chest CT with contrast should be considered to rule out other aetiologies. If the CT scan is negative, pulmonary function tests should be considered to identify a potential functional deficit
• Bronchoalveolar lavage to rule out infection or tumour infiltration and investigations for infection with sputum, blood and urine culture if clinically indicated should be considered
• In cases of grade 2 IR-pneumonitis, rechallenge with ICI therapy upon complete resolution of symptoms can be consideredon an individual basis with close monitoring 
• In cases of grade 2 IR-ILD, 1 mg/kg/day prednisolone (or equivalent) should be considered. For grade  3 IR-ILD, 1-2 mg/kg/day methylprednisolone i.v. or equivalent should be considered. CS tapering should be initiated after improvement to grade <1, over 4-6 weeks for grade 2 and over 6-8 weeks for grade 3
• If there is no improvement within 72 h of CS use, consultation with or referral to an expert should be arranged and therapeutic escalation should occur. Additional options include tocilizumab (8 mg/kg, one dose and every 2 weeks if needed), infliximab (5 mg/kg, one dose and every 2 weeks if needed) and IVIG (2 g/kg over 2-5 days).
• Other options, such as MMF (1 g twice daily)67 or cyclophosphamide, are possible