Table 2.

Case reports of patients developing enteritis without villous atrophy whilst on immune-checkpoint inhibitors for solid tumours.

Paper	Type of GI toxicity	Age/sex	Tumour	Oncological treatment	Symptoms	Upper GI endoscopic findings	Upper GI histology	Lower GI endoscopic findings	Lower GI histology	Treatment
Mohamed et al.26	Ileal perforation	52 F	Vulval melanoma	Ipilimumab/nivolumab	Abdominal pain; nausea; weight loss	Not performed	Not performed	Ileal perforation on laparotomy	Transmural ischaemic necrosis	Systemic steroids; infliximab; resection of terminal ileum
Smith et al.27	Ileitis	44 F	Melanoma	Ipilimumab/nivolumab	Diarrhoea	Not performed	Not performed	Microerosions of terminal ileum; normal colon	Ileum; increased eosinophils; villous congestion	Systemic steroids
Sokal et al.28	Diffuse enteritisa	48 F	Melanoma	Ipilimumab/nivolumab	Diarrhoea; fever; vomiting; weight loss	Normal	Non-specific acute duodenitis	Erythematous right colon; normal terminal ileum	Non-specific oedema on colonic and ileal biopsies	Systemic steroids
Sanders et al.29	Gastritis and terminal ileitis	43 M	Melanoma	Ipilimumab/nivolumab	Diarrhoea; nausea; vomiting; weight loss	Gastric erythema and spontaneous oozing of blood	Gastritis; duodenal inflammation	Ileal aphthous ulcers; normal colon mucosa	Ileal lamina propria lymphoplasmacytosis with eosinophilic infiltration	Systemic steroids; infliximab
Yang et al.30	Eosinophilic enteritis	68 M	Melanoma	Pembrolizumab, talimogene, laherparepvec, ipilimumab/nivolumab	Diarrhoea; abdominal pain; nausea; skin rash; cough	Normal	Marked eosinophilia (80–100/HPF) on duodenal biopsies	Not performed	Not performed	Systemic steroids
Young et al.31	Enteritis and small bowel bleeding	71 M	Colon adenocarcinoma	Atezolizumab	Diarrhoea; abdominal pain; massive GI bleeding	Multiple duodenal and jejunal ulcers on enteroscopy	Non-specific abnormalities	Normal	Normal	Systemic steroids; infliximab; jejunal resection
Otagiri et al.32	Enteritis	68 M	Pleural mesothelioma	Nivolumab	Diarrhoea; abdominal pain; melena; fever	Gastric and small bowel aphthous ulcers on OGD and CE	Not reported	Diffuse aphthous ulcers on colonoscopy	Not reported	Systemic steroids
Saito et al.33	Acute duodenal haemorrhage	66 M	Small-cell lung cancer	Carboplatin + etoposide + atezolizumab	Haematemesis; diarrhoea	Large duodenal ulcers with pulsatile bleeding	Duodenal lymphocyte, eosinophil and plasma cell infiltrate	Normal	Not reported	Endoscopic haemostasis; supportive therapy
Trystram et al.34	Diffuse ulcerative haemorrhagic enteritis	62 M	Melanoma	Ipilimumab/nivolumab	Fever; melena; haemorrhagic shock	Normal	Not reported	Multiple deep bleeding jejunal and ileal ulcers; ulcerated Meckel diverticulum	Non-specific ileitis	Systemic steroids; antibiotics; Meckel diverticulum resection; infliximab

^aAbdominal CT scan revealed diffuse small bowel wall thickening with contrast enhancement.

CE, capsule endoscopy; F, female; GI, gastrointestinal; HPF, high-power field; M, male; OGD, oesophagogastroduodenoscopy.