Use of Proton Pump Inhibitor and Risk of Colorectal Cancer: A Meta-analysis of Observational Studies / 가정의학회지

BACKGROUND: Previous case-control studies have reported inconsistent findings regarding the association between proton pump inhibitor (PPI) use and colorectal cancer (CRC) risk. We investigated these associations using meta-analysis. METHODS: We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library in April 2011. Two evaluators independently reviewed and selected articles, based on pre-determined selection criteria. RESULTS: Out of 737 articles meeting our initial criteria, 5 case-control studies, which involved 120,091 participants (9,514 cases and 110,577 controls), were included in the final analyses. The overall use of PPI (used vs. never or rarely used) was not significantly associated with the risk of CRC in a fixed-effects model meta-analysis of all 5 case-control studies (odds ratio [OR], 1.08; 95% confidence interval [CI], 0.96 to 1.20; I2 = 3.5%). Also, in sensitivity meta-analysis by cumulative duration of PPI use, there was no association between PPI use of 1 year or longer and the risk of colorectal cancer in a fixed-effects meta-analysis (OR, 1.09; 95% CI, 0.98 to 1.22; I2 = 0%). CONCLUSION: Although hypergastrinemia could be an important factor in the pathogenesis of some colorectal cancers, our study suggests that this does not lead to significant clinical risk for most PPI users. Further prospective studies or randomized controlled trials related to PPI use and colorectal cancer risk are needed to investigate this association.

Diagnostic Accuracy of Computed Tomography for the Lymph Node Staging of Endoscopically Resectable Early Gastric Cancer / 대한소화기내시경학회지

BACKGROUND/AIMS: Accurate staging of the lymph nodes (LNs) before endoscopic mucosal resection (EMR) is important. We evaluated the accuracy of CT for LN staging in patients the endoscopically resectable early gastric cancer (EGC). METHODS: The medical records of 155 EGCs patients who had undergone an operation were analyzed. The pre-operatively performed multidetector CT scans and the post-operative histopathologic findings were reviewed for comparing the LN staging with that using the Japanese classification system. Endoscopically resectable EGC was defined as EGC without LN metastasis and also the EGC that satisfied the EMR criteria according to the Japanese guideline. RESULTS: The diagnostic efficacy of CT for LN staging of all the enrolled EGC patients was as follow: accuracy 65.2%, overstaging rate 29.7%, understaging rate 5.2%. The overall accuracy and the overstaging rate of CT for LN staging of endoscopically resectable EGC were as follows: EGC without LN metastasis [69.8% (97/139), 30.2% (42/139)], EGC satisfying extended criteria [72.5% (58/80), 27.5% (22/80)] and EGC satisfying limited criteria [79.2% (19/24), 20.8% (5/24)]. The accuracy of the EMR criteria for predicting node negative EGC were as follows: the extended criteria 98.8% (79/80), the limited criteria 100% (24/24). CONCLUSIONS: Our study showed that prediction of LN metastasis before EMR according to CT staging had limited value due to the tendency of overestimation. Therefore, we should preferentially consider the treatment strategy according to the EMR criteria.