Radiation-induced gastrointestinal toxicity. Pathophysiology, approaches to treatment and prophylaxis.
BACKGROUND
Gastrointestinal toxicity is frequently observed during radiotherapy of malignancies in the abdomen and pelvis. The proposed pathophysiology of radiation enteritis is complex and a variety of different treatment strategies have been suggested for the management of acute radiation-induced diarrhea.


METHODS
Data are presented from an extensive review of the current literature.


RESULTS
Radiation-induced diarrhea results from a variety of different pathophysiological mechanisms including malabsorption of bile salts and lactose, imbalances in local bacterial flora and changes in the intestinal patterns of motility. Up to date acute radiation diarrhea is predominantly treated symptomatically using opioide derivates (loperamide) or adsorbants of bile salts such as smectite. Clinical trials have been performed using L. acidophilus, smectite or sucralfate for diarrhea prophylaxis with moderate reduction of acute symptoms.


CONCLUSIONS
Further evaluation of strategies for diarrhea prophylaxis is warranted. Due to the complex nature of radiation enteritis a multimodal approach taking into account alterations in intestinal motility patterns, malabsorption of bile salts and an imbalance of mucosal bacterial flora may offer new perspectives.
Classen
J
J
Abteilung für Strahlentherapie der Universität Tübingen. johannes.classen@uni-tuebingen.de
Belka
C
C
Paulsen
F
F
Budach
W
W
Hoffmann
W
W
Bamberg
M
M
D000008:Abdominal Neoplasms / Q000532:radiotherapy; D001647:Bile Acids and Salts / Q000378:metabolism; D003106:Colon / Q000382:microbiology; D003967:Diarrhea / Q000209:etiology / Q000503:physiopathology; D005767:Gastrointestinal Diseases / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control / Q000628:therapy; D005769:Gastrointestinal Motility; D006801:Humans; D007408:Intestinal Absorption; D010386:Pelvic Neoplasms / Q000532:radiotherapy; D011832:Radiation Injuries / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control / Q000628:therapy; D011878:Radiotherapy / Q000009:adverse effects*
D001647:Bile Acids and Salts