- Crohn disease
- Tumors
- Primary carcinoma
- Carcinoid
- Lymphoma
- Invasion from other organs
- Metastases
- Tuberculosis
- Actinomycosis
- Strongyloidiasis
- Anisakiasis
- Radiation injury
- Ischemia
- Intramural hemorrhage
- Diverticular mass
- Appendiceal mass
- Endometriosis
- Eosinophilic gastroenteritis
- Idiopathic ulcerative enteritis
- Behcet disease
- NSAIDs