Proton pump inhibitors, tumors

Less common causes of peptic ulceration include Zollinger-Ellison syndrome (ZES), cancer chemotherapy, radiation, and vascular insufficiency. ZES is caused by a gastrin-producing tumor called a gastrinoma and results in gastric acid hypersecretion. High-dose oral proton pump inhibitor (PPI) therapy is the initial treatment of choice for ZES intermittent intravenous PPI therapy may be required for any patient in whom oral therapy is contraindicated.1... 

There has been concern about the potential for proton pump inhibitors to cause enterochromaffin-hke cell hyperplasia, gastric carcinoid tumors and gastric cancers, colorectal polyps and adenocarcinoma, atrophic gastritis, and intestinal metaplasia in patients with H. pylori infection, and bacterial overgrowth. 

A gastric carcinoid tumor, detected during long-term anti-ulcer therapy with a histamine receptor antagonist and proton pump inhibitors, has been reported (34). 

De Milito, A. Pais, S. Tumor acidity, chemoresistance and proton pump inhibitors. Future Oncol. 2005, 1, 779-786. 

The proton pump inhibitors are usually well tolerated however, potential adverse effects include headache, dizziness, somnolence, diarrhea, constipation, and nausea. The frequency of adverse events appears to be similar to that seen with the H2-receptor antagonists. Concern and controversy regarding the safety of therapy with a proton pump inhibitor are based on the proton pump inhibitor s ability to cause hypergastrinemia and gastric carcinoid tumors in rats. After nearly a decade of experience with the proton pump inhibitors, gastric carcinoid tumors have not been directly linked to omeprazole use in humans. ... 

De, M.A. and Fais, S. (2005) Tumor addity, diemoresistance and proton pump inhibitors. Future Oncology (London, Errand), 1, 779 6. 

Sato, N. Suzuki, N. Yamaguchi, M. Yamaguchi, N. Okuma, K. Proteolipid subunits of vacuolar H" -ATPase (ATP6F) as tumor antigens, application to cancer therapy, and use of proton pump inhibitor as anticancer agent. Jpn. Kokai Tokkyo Koho JP 2001286284,2001 Chem. Abstr. 2001,135, 314438. 

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