Esophageal cancer: Risk factors, screening and endoscopic treatment in Western and Eastern countries

Table 1 Risk factors for squamous cell carcinoma and adenocarcinoma of the esophagus

Risk factor	Squamous cell carcinoma	Adenocarcinoma
Geography	Southeastern Africa, Asia, Iran, South America	Western Europe, North America (United States), Australia
Race	Black > White	White > Black
Gender	Male > Female	Male > Female
Alcohol	++++	-
Tobacco	++++	++
Obesity	-	+++
GERD	-	++++
Diet: Low fruits and vegetables	++	+
Socioeconomic conditions	++	-
Genetic aspects	++	+

GERD: Gastroesophageal reflux disease; +: Associated risk; -: No risk associated. Modified from[4].

Table 2 TNM esophageal cancer

T: Primary tumor:
Tx: It can not be evaluated
T0: No evidence of primary tumor
Tis: High-grade dysplasia (intra-epithelial neoplasia noninvasive)
T1: Tumor invades own lamina, muscularis mucosae and submucosa:
T1a: Tumor invades own lamina or muscularis mucosae
T1b: Tumor invades the submucosa
T2: Tumor invades the muscularis
T3: Tumor invades the adventitia
T4: Tumor invades adjacent structures:
T4a: Tumor invades resectable pleura, pericardium, or diaphragm
T4b: Unresectable tumor that invades other adjacent structures: aorta, vertebral body, trachea, etc.
N: Regional lymph nodes:
Nx: They can not be evaluated
N1: Metastasis in 1-2 regional lymph nodes
N2: Metastasis in 3-6 regional lymph nodes
N3: Metastasis in 7 or more regional lymph nodes
M: Distant metastasis:
M0: None
M1: There are distant metastases

Modified from AJCC 2010[29].