Effectiveness of the small-diameter panendoscope in diagnosing cancers of the upper gastrointestinal tract

Performance of different gastric cancer screening methods in Korea: a population-based study

Background

There is a lack of agreement on which gastric cancer screening method is the most effective in the general population. The present study compared the relative performance of upper-gastrointestinal series (UGIS) and endoscopy screening for gastric cancer.

Methods

A population-based study was conducted using the National Cancer Screening Program (NCSP) database. We analyzed data on 2,690,731 men and women in Korea who underwent either UGIS or endoscopy screening for gastric cancer between January 1, 2002 and December 31, 2005. Final gastric cancer diagnosis was ascertained through linkage with the Korean Central Cancer Registry. We calculated positivity rate, gastric cancer detection rate, interval cancer rate, sensitivity, specificity, and positive predictive value of UGIS and endoscopy screening.

Results

The positivity rates for UGIS and endoscopy screening were 39.7 and 42.1 per 1,000 screenings, respectively. Gastric cancer detection rates were 0.68 and 2.61 per 1,000 screenings, respectively. In total, 2,067 interval cancers occurred within 1 year of a negative UGIS screening result (rate, 1.17/1,000) and 1,083 after a negative endoscopy screening result (rate, 1.17/1,000). The sensitivity of UGIS and endoscopy screening to detect gastric cancer was 36.7 and 69.0%, respectively, and specificity was 96.1 and 96.0%. The sensitivity of endoscopy screening to detect localized gastric cancer was 65.7%, which was statistically significantly higher than that of UGIS screening.

Conclusion

Overall, endoscopy performed better than UGIS in the NCSP for gastric cancer. Further evaluation of the impact of these screening methods should take into account the corresponding costs and reduction in mortality.

Mass screening for gastric cancer: how to select patients for endoscopic examination

BACKGROUND

Gastroendoscopy (GS) has recently been applied in mass screening for gastric cancer, instead of X-ray examination, to improve the quality of the screening. However, as there are currently limitations in the application of endoscopy in all types of screening for gastric cancer, patients must be selected for mass screening by endoscopy. We investigated how to select individuals for endoscopic examination of gastric cancer screening and the effectiveness of X-ray primary screening before endoscopy.

METHODS

All 7942 patients who underwent upper endoscopy for gastric cancer screening at our hospital between April 2005 and March 2008 were divided into two groups: an X-ray screening group (2782 subjects, endoscopy following primary X-ray screening), and a GS direct group (5160 subjects, endoscopy only).

RESULTS

Thirty-seven carcinomas were detected among the 2782 subjects in the X-ray screening group undergoing endoscopy, representing a cancer detection rate of 1.33%. In the GS direct group, 23 carcinomas were detected in the 5160 subjects undergoing endoscopy, representing a cancer detection rate of 0.45%. However, our results suggested that the gastric cancer detection rate by endoscopy was three times higher when it was performed following X-ray screening.

CONCLUSION

There are various conflicting demands for future screening. Our results suggest that it is appropriate to perform an initial X-ray examination followed by endoscopy in prospective screening for gastric cancer.

Impact of screening survey of gastric cancer on clinicopathological features and survival: retrospective study at a single institution

BACKGROUND

Detection of gastric cancer in an early stage is important to improve the prognosis of patients with gastric cancer. This study compared the clinicopathologic characteristics and surgical results in patients with asymptomatic gastric cancer detected by a screening program with those of patients with symptomatic cancer. The efficacy of 2 screening methods (barium meal and endoscopy) was also compared.

METHODS

The subjects included 196 patients with asymptomatic gastric cancer detected by screening (screening group) and 612 patients with symptomatic gastric cancer (nonscreening group) treated from 1979 to 1997. The screening group was subdivided into the barium meal study group (n = 150) and the endoscopic study group (n = 46).

RESULTS

The incidences of early gastric cancer and 5-year survival rates between the screening and nonscreening groups were 77% versus 29% (P <.0001) and 81% versus 44% (P <.0001), respectively. The endoscopic study appeared to be able to detect smaller gastric cancer in an earlier stage compared with the barium meal study, although no statistical differences in survival rate were noted between these 2 screening methods.

CONCLUSIONS

Screening plays an important role in detecting gastric cancer in an early stage and in potentially reducing death attributable to gastric cancer. Endoscopic screening is recommended as the best screening method.