Risken att utveckla bukspottkörtelcancer, levercancer eller magcancer vid långtidsbehandling med protonpumpshämmare : Litteraturstudie som utvärderar säkerheten av att använda magsyrahämmande läkemedel

Sammanfattning: Gastric ulcer is defined as an open sore of the gastric mucosa or intestinal wall. It affects approximately 5-10% of the world population. The ulcers can be situated either in the lower region of stomach mucosa (gastric ulcer) or upper region of duodenum mucosa (duodenal ulcer). The condition can be described as a chronic disease due to inadequate healing of the ulceration and is exhibited as a periodic epigastric pain in patients. Some of the factors that can cause stomach ulcers are H. pylori infection, certain drugs and stress. Treatment strategies aim at reducing the factors that damage the gastric mucosa, such as hydrochloric acid (HCl). Pharmaceutical drugs that perform this are proton pump inhibitors (PPI) and Histamine-2 receptor antagonists (H2RA), among others, that by various mechanisms inhibit gastric acid production in the stomach. According to statistics from National Board of Health and Welfare (Socialstyrelsen), the daily dosage of stomach acid per patient has risen over 70% from 2006 to 2015, of which most consumers were women in the  ages between 15-29 years. The aim of this study was to investigate the occurrence of pancreatic, liver and gastric cancers with long-term treatment (>6 months) of proton-pump inhibitors. This work was a literature study that was conducted by searching through PubMed and Web of Science databases. The search-phrases used were " Use of Proton Pump Inhibitor and Risk of cancer long term," which resulted in 108 scientific articles. The inclusion criteria were English, long-term (>6 months) PPI-treatment, epidemiological studies that study people with: gastric ulcer, GERD and/or H. pylori infection and is compared to development of some type of cancer. Thereafter, two nested case-control studies, three population-based control studies and one meta-analysis were chosen for analysis. Studies 1, 2 and 4 concluded that PPI use is correlated with increased risk of cancer of pancreatic cancer and liver cancer. The results of study 2 showed that with more frequent PPI use, the risk of gastric cancer development increased by 2.4 times compared to non-PPI users. The results of study 3 showed a progressive increase in the risk of gastric cancer with more frequent use of PPI. Study 4 suggested that the risk for pancreatic cancer development was greatest among active users. Unlike the rest of the studies, study 4 claimed that cancer development risk decreased with longer PPI treatment time. Study 5 suggested that the mortality rate of PPI users was somewhat smaller than that of H2RA users. However the results also showed that with a PPI treatment duration of over 5 years, the risk of stomach cancer begins to decrease. Contrary to other studies, the results from Study 6 have shown that there was no link between PPI use and the risk of colorectal cancer (CRC) development, and that the risk of CRC development was independent of the duration of PPI use. All studies, except for study 6, have shown a possible relationship between PPI use and the occurrence of some form of cancer such as gastric cancer, liver cancer and pancreatic cancer in long-term treatment with PPI. The correlation between PPI usage and the risk of cancer development is relatively low (OR 1.6) in comparison with the correlation between e.g. smoking and the risk of development of lung cancer (OR 17.59). In conclusion, there is a weak association between the long-term treatment of PPI medication on elderly patients (65+ years old) and an increase in the risk of development of different types of cancer, such as gastric, liver and pancreatic cancers.