Radiation colitis

WikiDoc Resources for Radiation colitis
Articles
Most recent articles on Radiation colitis Most cited articles on Radiation colitis Review articles on Radiation colitis Articles on Radiation colitis in N Eng J Med, Lancet, BMJ
Media
Powerpoint slides on Radiation colitis Images of Radiation colitis Photos of Radiation colitis Podcasts & MP3s on Radiation colitis Videos on Radiation colitis
Evidence Based Medicine
Cochrane Collaboration on Radiation colitis Bandolier on Radiation colitis TRIP on Radiation colitis
Clinical Trials
Ongoing Trials on Radiation colitis at Clinical Trials.gov Trial results on Radiation colitis Clinical Trials on Radiation colitis at Google
Guidelines / Policies / Govt
US National Guidelines Clearinghouse on Radiation colitis NICE Guidance on Radiation colitis NHS PRODIGY Guidance FDA on Radiation colitis CDC on Radiation colitis
Books
Books on Radiation colitis
News
Radiation colitis in the news Be alerted to news on Radiation colitis News trends on Radiation colitis
Commentary
Blogs on Radiation colitis
Definitions
Definitions of Radiation colitis
Patient Resources / Community
Patient resources on Radiation colitis Discussion groups on Radiation colitis Patient Handouts on Radiation colitis Directions to Hospitals Treating Radiation colitis Risk calculators and risk factors for Radiation colitis
Healthcare Provider Resources
Symptoms of Radiation colitis Causes & Risk Factors for Radiation colitis Diagnostic studies for Radiation colitis Treatment of Radiation colitis
Continuing Medical Education (CME)
CME Programs on Radiation colitis
International
Radiation colitis en Espanol Radiation colitis en Francais
Business
Radiation colitis in the Marketplace Patents on Radiation colitis
Experimental / Informatics
List of terms related to Radiation colitis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Qasim Salau, M.B.B.S., FMCPaed [2]

Synonyms and keywords:

Overview

Radiation therapy is a common treatment modality for Abdominal and pelvic malignancy. Radiation colitis may complicate this radiotherapy. Radiation colitis tends to develop insidiously and it is often progressive.

Pathophysiology

• Occur following radiation therapy for Abdominal and pelvic malignancies .
• More common with radiation doses higher than 45Gy.
• The main site of damage is the DNA. May also affect RNA, proteins and cell membranes.
  • Injury occur few hours to days, up to three months after irradiation in acute radiation colitis. It affects rapidly dividing cells of the epithelium and mucosa. This leads to cell death, recruitment and activation of polymorphonuclear (PMN) inflammatory cells, mucosal edema and damage to small blood vessels. It is usually transient and self limiting, with regeneration of the epithelium.
  • In chronic radiation colitis, mesenchymal tissue is involved. The damage is progressive with atrophy of the mucosa, fibrosis of the intestinal wall, obliteration of small arteries, chronic ischemia, ulcers, strictures and fistula formation. This changes usually occur three months to years after radiation. Secondary colonic malignancy may occur.

Genetics

There is no specific genetic cause for radiation colitis.

Gross Pathology

Endoscopy should be gentle and with care especially in acute radiation colitis.

• The mucosa may appear erythematous or pale, is edematous, friable with or without small erosions in acute radiation colitis.
• In chronic radiation colitis, mucosa atrophy, fibrosis, obliterative arteritis, stenosis, strictures, fistula and ulcers are seen.

Microscopic Histopathology

Histopathological findings of radiation colitis may be categorized into the following

• Acute: Reduced mitosis, increased apoptosis bodies, mucin depletion, eosinophilia, presence of crypt abscesses and evidence of regeneration
• Chronic: Dilated capillaries and lymphatics, hyaline fibrosis, atypical fibroblast and endothelial cells and distortion of the crypts.

Differentiating radiation colitis from other Diseases

Symptoms of acute radiation proctitis may overlap with other causes of acute colitis, but prior history of radiation will help in distinguishing the cause. Differential diagnosis of acute radiation colitis include:

• Allergic colitis
• Chemical colitis
• NSAID induced colitis
• Ischemic colitis

Differential diagnosis of chronic radiation colitis include:

• Ischemic colitis
• Inflammatory bowel disease

Epidemiology and Demographics

Gender

Men and women are affected equally by radiation colitis.

Race

There is no racial predilection to radiation colitis.

Risk Factors

Common risk factors for developing radiation colitis include:

• Radiation dose greater than 54 Gy
• Elderly (above 60 years)
• Past radical abdominal or pelvic surgery such as radical hysterectomy and radical colectomy
• Asthenic individuals
• Smoking
• Chronic co-morbid medical problems such as diabetes mellitus, hypertension and artherosclerosis
• Past pelvic inflammatory disease
• Collagen vascular disease
• HIV infection- Hypothesized to increase risk for radiation toxicity in the colon

Treatment

Prevention

• There are no primary preventive measures available for [disease name].

• Effective measures for the primary prevention of [disease name] include [measure1], [measure2], and [measure3].