Benefits and harms of endoscopic screening for gastric cancer

Table 1 Comparison of results from cohort studies of endoscopic screening for gastric cancer

Author	Riecken et al[9]	Matsumoto et al[10]	Hosokawa et al[11]	Hamashima et al[12]	Hamashima et al[13]
Publication	2002	2007	2011	2015	2015
Country	China	Japan	Japan	Japan	Japan
Target age, yr	35-64	≥ 40	Average: 50.0	40-79	40-79
Follow-up, yr		9	5	5	6
Number of subjects	4364	7178	18011	16373	9950
Comparators	-	-	Radiographic screening	-	Radiographic screening
Number of comparators	-	-	36870	-	4324
Outcome indicators	SMR	SMR	Hazard ratio (HR)	SMR	Relative risk
Main results	1.01	Male: 0.71	HR = 0.15	0.43	Adjusted RR2
	(95%CI: 0.72-1.37)	(95%CI: 0.33-1.10)	(95%CI: 0.05-0.50)	(95%CI: 0.30-0.57)	0.327
		Female: 0.62	Adjusted HR1 = 0.23		(95%CI: 0.118-0.908)
		(95%CI: 0.19-1.05)	(95%CI: 0.07-0.76)

¹Adjusted HR by sex and age;

²Adjusted RR by sex, age group, and resident city. SMR: Standard mortality ratio; CI: Confidence interval; HR: Hazard ratio; RR: Relative risk.

Table 2 Comparison of results from case-control studies of endoscopic screening for gastric cancer

Author	Matsumoto et al[14]	Hamashima et al[15]	Cho[17]
Publication	2014	2013	2013
Country	Japan	Japan	South Korea
Target age, yr	54-91	40-79	≥ 40
Number of cases	13	410	35457
Number of control	130	2292	141828
Comparator	Never-screened	Never-screened	Never-screened
Main results	0.206	0.695	0.430
	(95%CI: 0.044-0.965)	(95%CI: 0.489-0.986)	(95%CI: 0.40-0.46)

Table 3 Sensitivities and specificities of endoscopy and radiography for gastric cancer screening

Screening round	Method	Sensitivity	Specificity	Sensitivity
		by the detection method	by the detection method	by the incidence method
Prevalence screening	Endoscopic screening	0.955	0.851	0.886
		(95%CI: 0.875-0.991)	(95%CI: 0.843-0.859)	(95%CI: 0.698-0.976)
	Radiographic screening	0.893	0.856	0.831
		(95%CI: 0.718-0.977)	(95%CI: 0.846-0.865)	(95%CI: 0.586-0.964)
Incidence screening	Endoscopic screening	0.977	0.888	0.954
		(95%CI: 0.919-0.997)	(95%CI: 0.883-0.892)	(95%CI: 0.842-0.994)
	Radiographic screening	0.885	0.891	0.855
		(95%CI: 0.664-0.972)	(95%CI: 0.885-0.896)	(95%CI: 0.637-0.970)

Adapted from Hamashima et al[19].