[Prevention of radiation-induced diarrhea by smectite. Results of a double-blind randomized, placebo-controlled multicenter study]. / Prophylaxe der strahleninduzierten Diarrhö durch Smektit. Ergebnisse einer doppelblind randomisierten, plazebokontrollierten Multicenterstudie.

PURPOSE: Diarrhea and abdominal pain are well-known side effects abdominal or pelvic of radiation therapy that may lead to interruption of treatment in serious cases. In recent trials the silicate smectite has proven a promising drug in the prophylaxis of these adverse events. The presented trial aimed at the verification of earlier studies and the evaluation of a dose-effect relationship. PATIENTS AND METHODS: Between April 1994 and May 1995, a total of 176 patients obtaining radiotherapy of the pelvis or the abdomen were evaluated in a double-blind, randomized placebo-controlled investigation regarding the prophylactic effect of smectite (= Colina) against radiotherapy-induced diarrhea. During the whole period of radiotherapy 85 patients obtained 2 x 6 g smectite daily and 91 patients received 2 x 6 g placebo. The primary end point of the analysis was the time to the first appearance of diarrhea (> or = 3 pappy stools). RESULTS: All 176 patients were evaluated according to an intent-to-treat analysis. There was no significant difference between the prophylactic effects of smectite and placebo. For an explorative post-hoc analysis the total study group was split up into 2 subgroups, one with an irradiated small bowel volume < or = 837.5 ml, the other with a small bowel volume > 837.5 ml (median); the analysis indicated that the first subgroup showed a benefit for the smectite-treated patients in contrast to the placebo treatment (32 vs. 18 calendar days to the first appearance of diarrhea). This benefit was statistically not significant. CONCLUSION: Prophylactic application of smectite during irradiation of the pelvis and the abdomen can delay the development of radiotherapy-induced diarrhea, a statistical significance could not be verified neither in the total study group nor in the post-hoc subgroup analysis.

[Therapy trends in the prevention of radiation-induced diarrhea after pelvic and abdominal irradiation. Results of a tricenter study]. / Therapieansätze zur Prophylaxe der strahleninduzierten Diarrhoe nach Becken- und Abdominalbestrahlung. Ergebnisse einer trizentrischen Untersuchung.

PURPOSE: Radiotherapy induced diarrhea and convulsive pain are severe side-effects of irradiation of the pelvis and the abdomen leading often to an interruption of the treatment. Up to now these side-effects were only treated symptomatically, prophylactic therapies are not known. PATIENTS AND METHODS: During the years 1992 and 1993 174 patients who obtained radiotherapy in the pelvis or the abdomen because of different malignancies were observed referring to the diarrhea-prophylactic effect of Smectite (= Skilpin). 80 patients received Smectite at the beginning of radiotherapy, 94 patients of the control group were treated with motility modifying drugs when diarrhea appeared. The following parameters were compared: Frequency, consistence and incontinence of stool, tenesmus and the onset of diarrhea. RESULTS: 67.0% (n = 63) of the patients in the control group developed diarrhea, whereas in the pretreated Smectite-group only 37.5% of the cases (n = 30) developed diarrhea. The first appearance of diarrhea was at day 17 in the pretreated group and averagely at day 11 in the control group. 44% of the patients in the control group suffered from tenesmus versus 25% in the Smectite-group. CONCLUSION: In comparison to the symptomatic treatment of radiation enteritis the prophylactic application of Smectite is able to reduce the diarrhea from the beginning of radiotherapy or at least to reduce the pathological frequency of stool and therefore to increase the quality of life.