Misoprostol and omeprazole in the prevention of chemotherapy-induced acute gastroduodenal mucosal injury. A randomized, placebo-controlled pilot study.

BACKGROUND

Chemotherapy (CT) may induce acute mucosal injury to the stomach and duodenum, but its prevention has been scarcely investigated.

METHODS

One hundred and eighty-two cancer patients with normal stomach and duodenum or having fewer than 3 erosions, selected to be treated with cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) (77 breast carcinoma patients) or 5-fluorouracil (5-FU) (105 colon carcinoma patients), were randomly assigned to prophylactic treatment with misoprostol, 400 micrograms twice a day; omeprazole, 20 mg once a day; or placebo, 1 tablet twice a day. Seven days after the end of the second source of CT, all patients underwent control esophagogastroduodenoscopy. Endoscopic findings were quantified on the basis of an arbitrary score: 0 = normal; 1 = less than 3 erosions; 2 = 3-15 erosions; 3 = more than 15 erosions or ulcer; 4 = giant ulcer (greatest dimension of more than 2 cm) or multiple ulcers with cumulative greatest dimension exceeding 2 cm.

RESULTS

Mean score increased significantly in the placebo and misoprostol groups, either after CMF (P < 0.001 and P < 0.05, respectively) or after 5-FU (P < 0.001 for both), whereas it did not in the omeprazole group. Gastric and duodenal ulcers were significantly less frequent in patients receiving omeprazole than in those receiving placebo (P < 0.05 after both CMF and 5-FU). No significant difference was observed between placebo and misoprostol. Omeprazole was significantly more effective than placebo and misoprostol in reducing the frequency and degree of the endoscopic worsening, either after CMF or after 5-FU (P < 0.05 for both CT regimens). Epigastric pain and/or heartburn were significantly less frequent in patients receiving omeprazole than in those receiving placebo (P < 0.01) or misoprostol (P < 0.001).

CONCLUSIONS

The strong and prolonged inhibition of gastric acid production induced by omeprazole seems to be effective in preventing chemotherapy-induced gastroduodenal mucosal injury. Further trials are necessary to verify whether such a prevention of endoscopically observed injury can translate into prevention of clinically significant injury.