Value of screening endoscopy in evaluation of esophageal, gastric and colon cancers

Table 1 Accuracy of endoscopic modalities in esophageal carcinoma, which reveal the efficacy of endoscopic screening

Type of study	BE/ESCC	Patient group	Disease prevalence (%)	Accuracy of screen (%)
Endoscopic screening
Prospective	ESCC	Asymptomatic; Linxian, China	ESCC: 9.5	Relative risk of ESCC: 2.9/9.8/28.3 (mild/moderate/sever dysplasia); 34.4 (carcinoma in situ)
Prospective	ESCC	Asymptomatic; Linxian, China	Not determined	Sensitivity/specificity for high-grade dysplasia or ESCC: 62/79 (visible lesions); 96/63 (unstained lesions)
Ultrathin endoscopes
Randomized crossover	BE	GERD; United States	Not determined	Sensitivity: 26/30 (standard/small caliber endoscopy)
Randomized crossover	BE	BE and controls; United Kingdom	Not determined	Sensitivity/specificity small vs standard caliber: 100/100
Capsule endoscopy
Prospective single screen	BE	GERD and under surveillance BE; United States	Not determined	Sensitivity/specificity for BE: 67/84
Prospective single screen	BE	GERD; United States	Not determined	Sensitivity/specificity for BE: 60/100
Prospective single screen	BE	GERD; United States	Not determined	Sensitivity/specificity for BE: 78/82 (visual lesions); 93/78 (biopsy)

Adapted from Lao-Sirieix et al[11]. BE: Barrett’s esophagus; ESCC: Esophageal squamous cell cancer; GERD: Gastro-esophageal reflux disease.

Table 2 Different screening modalities

Modality	Sensitivity (95%CI)	Specificity (95%CI)	PPV (95%CI)	NPV (95%CI)	Accuracy (95%CI)
WL	47.3%	97.4%	79.4%	89.8%	88.7%
NBI	84.2%	95.6%	80.0%	96.6%	93.6%
Lugol1	93.0%	90.7%	67.9%	98.4%	91.1%
NBI or Lugol	94.7%	90.4%	67.5%	98.8%	91.1%
NBI or Lugol	82.6%	95.9%	81.0%	93.6%	93.6%

¹Lugol is iodine staining solution used in chromoendoscopy. Adapted from Wang et al[26].

Table 3 Five-year survival rates by stage for stomach cancer treated with surgery

Stage	5-year observed survival rate
Stage IA	71%
Stage IB	57%
Stage IIA	46%
Stage IIB	33%
Stage IIIA	20%
Stage IIIB	14%
Stage IIIC	9%
Stage IV	4%

Adapted from National Cancer Institute’s SEER database[40].

Table 4 Endoscopy used in cancer screening

Ref.	Number of Subjects	Sensitivity	Specificity	PPV
Hamashima et al[44], 2013	EGD: 7388	88.60%	85.10%	5.50%
		(69.8-97.6)1	(84.3-85.9)1	(4.3-7.0)1
	Upper GI series: 5410	83.10%	85.60%	4.30%
		(58.6-96.4)1	(84.6-86.5)1	(3.4-5.2)1
Choi et al[43,45], 2011	EGD: 924822	66.90%	96.20%	5.30%
		(59.8-74.0)1	(95.7-96.7)1	(4.8-5.9)1
	Upper GI series: 1765909	27.30%	96.60%	1.30%
		(22.6-32.0)1	(96.3-97.0)1	(1.1-1.6)1

¹The 95% confidential intervals are given in parentheses[35]. Adapted from Choi et al[43].

Table 5 Risk factors and proposed screening recommendations for gastric cancer

Risk factors	Risk for developing gastric cancer	Recommendation	First author
Helicobacter pylori infection	Odds ratio (OR): 2.3	High risk area - mass screening possible benefit	Huang, 1998
		Low risk area - mass screening not cost-effective
Pernicious anemia	Standardized incidence ratio: 5	Screening by upper endoscopy (UE) recommended	Kokkola, 1998
Partial gastrectomy	15-24 yr, RR = 9.4	Screening by UE recommended	Lundegardh, 1988
	25-46 yr, RR = 55.6		Tersmette, 1991
Familial adenomatous polyposis	Not available	Screening by UE recommended	Alexander, 1989
Hereditary nonpolyposis colorectal cancer	Not available	Screening by UE recommended	Aarnio, 1997
Positive family history of gastric cancer	OR: 2.5-5.1	HP eradication +/- UE screening	Yatsuya, 2004
			Chen, 2004

Adapted from Chan et al[48].

Table 6 Colorectal cancer screening guidelines for the United States

Guidelines for screening for the early detection of colorectal cancer and adenomas for average-risk women and men aged 50 yr and older
Test	Interval
Tests that detect adenomatous polyps and cancer
FSIG with insertion up to 40 cm from anal verge or to splenic flexure	Every 5 yr
Colonoscopy	Every 10 yr
DCBE	Every 5 yr
CTC	Every 5 yr
Tests that primarily detect cancer
gFOBT	Annual
FIT	Annual
sDNA	Interval uncertain

Adapted from Levin et al[59]. FSIG: Flexible sigmoidoscopy; DCBE: Double-contrast barium enema; CTC: Computed tomography colonography; gFOBT: Guaiac-based fecal occult blood test; FIT: Fecal immunochemical test; sDNA: Stool DNA test.

Table 7 Different image-enhanced endoscopy

Type	Mode(solution/instrument)	Mechanism of contrast
Dye-based IEE (chromoscopy)
Dye enhancement
Contrast dye indigo carmine	0.1%-0.4% solution	Dye pools in mucosal crevices; no cellular staining
	For 0.2% dilution, mix 5 mL 0.8% solution) with 15 mL sterile water
Equipment-based IEE
Optical enhancement
Narrow band imaging	Olympus	Modification of light source with narrowed wavelengths to enhance capillary patterns
Electronic enhancement
Spectral estimation technology	Fujinon	Processing of image to enhance capillary patterns
Surface enhancement	Pentax	Processing of image to enhance color pattern or structure (I-Scan Technology)

Adapted from Ko[72]. IEE: Image-enhanced endoscopy.