Radiation Colitis

Epidemiology:

Common sites:

Gross features:

• acute:
• patchy erythema on colonoscopy
• edema
• ulcers
• delayed:
• ischemia-related findings:
• ulcers
• strictures
• fistulas
• adhesions

Histologic features:

• acute (rarely seen):
• epithelial damage
• increased apoptosis
• decreased mitoses
• regenerative atypia
• increased eosinophils maybe
• Chronic:
• Telangectasia of mucosal capillaries
• Hyalinization around vessels and in lamina propria
• “radiation fibroblasts” – atypical
• regenerative
• atypia of endothelial cells maybe
• crypt distortion to a degree
• foci of cryptitis maybe
• superimposed changes of ischemia

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

Other features:

• acute injury:
• hours to days, heals within 2 months of exposure
• chronic injury is mostly due to ischemic damage to mesenteric vessels
• damage is permanent
• loss of electrolytes
• susceptibility to infection
• induction of cancers

References:

• Foundations in Diagnostic Pathology – Gastrointestinal and Liver Pathology 2006