Current issues and future perspectives of gastric cancer screening

Table 1 Results of population-based screening in Japan

	Stomach	Colon and rectum	Lung	Breast	Cervix
Total participants	3874128	6975281	7059318	2541993	4666826
Screening rate	9.6%	16.8%	17.2%	18.8%	23.7%
Positive rate	9.4%	7.3%	2.8%	8.6%	1.6%
Participant rate of diagnostic examination	81.1%	63.6%	77.7%	83.5%	66.2%
Cancer detection rate	0.17%	0.23%	0.06%	0.32%	0.08%
Positive predictive value	1.9	3.2	2.2	3.7	4.9

Adapted from reference [7].

Table 2 Sensitivity 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
		(0.875-0.991)	(0.843-0.859)	(0.698-0.976)
	Radiographic screening	0.893	0.856	0.831
		(0.718-0.977)	(0.846-0.865)	(0.586-0.964)
Incidence screening	Endoscopic screening	0.977	0.888	0.954
		(0.919-0.997)	(0.883-0.892)	(0.842-0.994)
	Radiographic screening	0.885	0.891	0.855
		(0.664-0.972)	(0.885-0.896)	(0.637-0.970)

Adapted from reference [22].

Table 3 Results of prediction based on a combination of Helicobacter pylori antibody and serum pepsinogen screening

	Ohata et al[38]	Watabe et al[40]	Mizuno et al[39]
Basic characteristics
Year published	2004	2005	2009
Location	Wakayama	Chiba	Kyoto
Total number	4655	6983	2859
Men/Women	4655/0	3320/2260	1011/1848
Age	48.3 (average)	48.9 (average)	≥ 35
Follow-up (yr)	7.7 (average)	4.7 (average)	10 (maximum)
HP positive rate (%)	78.6	46.1	75
PG positive rate (%)	28.9	21.8	39.2
Number of detected cancer	45	43	61
Incidence of gastric cancer (/1000)	9.67	6.16	21.3
HP-/PG-
Total number	967	3324	647
Number of detected cancer	0	7	2
Incidence of gastric cancer (/1000)	-	2.11	3.09
HP+/PG-
Total number	2341	2134	1094
Number of detected cancer	19	6	15
Incidence of gastric cancer (/1000)	8.12	2.81	13.71
HP+/PG+
Total number	1316	1082	1054
Number of detected cancer	24	18	41
Incidence of gastric cancer (/1000)	18.24	16.64	38.9
HP-/PG+
Total number	31	443	69
Number of detected cancer	2	12	3
Incidence of gastric cancer (/1000)	64.52	27.09	43.48

HP: Helicobacter pylori antibody; PG: Serum pepsinogen.

Table 4 Biomarker development process

Phase No.	Aim	Detail
Phase 1	Preclinical Exploratory	Promising directions identified
Phase 2	Clinical Assay and Validation	Clinical assay detects established disease
Phase 3	Retrospective Longitudinal	Biomarker detects disease early before it becomes clinical and a “screen positive” rule is defined
Phase 4	Prospective Screening	Extent and characteristics of disease detected by the test and the false referral rate are identified
Phase 5	Cancer Control	Impact of screening on reducing the burden of disease on the population is quantified

Adapted from reference [32].