Objective: We investigated the incidence of side effects related to contrast medium employed in our hospital based on monitoring materials to improve the safety of contrast-enhanced examinations.  Furthermore, we compared the incidence of side effects between the original product and generic drugs to confirm the safety of each preparation.
Methods: The survey period was from April 2007 until March 2011.  Based on the number of patients who underwent contrast-enhanced examinations and that of patients with side effects, we calculated the incidence of side effects in our hospital, and confirmed its annual changes.  Subsequently, we again collected the incidence of side effects per each manufacturer’s preparation employed, and confirmed the state of side effects of individual preparations.  Furthermore, we evaluated the symptoms as side effects, interval until appearance, and treatment for side effects during the data collection period, as well as the subsequent state, symptoms as side effects, and interval until appearance.  The chi square independence test was employed to compare the results among groups.  p<0.05 was regarded as significant (paired test).
Results: There were no changes in the annual incidence of side effects.  There were also no significant differences in the annual incidence of side effects among the preparations.  Furthermore, there were no marked differences in the symptoms, interval until appearance, treatment for side effects, or subsequent state among the preparations.
Conclusion: We investigated the appearance of side effects regarding contrast-enhanced examinations for 4 years.  We confirmed that there were no differences in the incidence of side effects among the preparations.

Purpose: Promoter DNA methylation of various genes has been associated with metachronous gastric cancer (MGC). The cancer-specific methylation gene, cysteine dioxygenase type 1 (CDO1), has been implicated in the occurrence of residual gastric cancer. We evaluated whether DNA methylation of CDO1 could be a predictive biomarker of MGC using specimens of MGC developing on scars after endoscopic submucosal dissection (ESD). Materials and Methods: CDO1 methylation values (TaqMeth values) were compared between 33 patients with early gastric cancer (EGC) with no confirmed metachronous lesions at >3 years after ESD (non-MGC: nMGC group) and 11 patients with MGC developing on scars after ESD (MGCSE groups: EGC at the first ESD [MGCSE-1 group], EGC at the second ESD for treating MGC developing on scars after ESD [MGCSE-2 group]). Each EGC specimen was measured at five locations (at tumor [T] and the 4-point tumor-adjacent noncancerous mucosa [TAM]). Results: In the nMGC group, the TaqMeth values for T were significantly higher than that for TAM (P=0.0006). In the MGCSE groups, TAM (MGCSE-1) exhibited significantly higher TaqMeth values than TAM (nMGC) (P<0.0001) and TAM (MGCSE-2) (P=0.0041), suggesting that TAM (MGCSE-1) exhibited CDO1 hypermethylation similar to T (P=0.3638). The area under the curve for discriminating the highest TaqMeth value of TAM (MGCSE-1) from that of TAM (nMGC) was 0.81, and using the cut-off value of 43.4, CDO1 hypermethylation effectively enriched the MGCSE groups (P<0.0001). Conclusions CDO1 hypermethylation has been implicated in the occurrence of MGC, suggesting its potential as a promising MGC predictor.