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The incidence of esophageal cancer has steadily increased while the incidence of gastric cancer has decreased in the United States for over a half century. Over the past several decades, the incidence of tumors in the distal esophagus/gastroesophageal junction and cardia is rising. The highest rates of esophageal cancer are found in East Asia, Eastern Africa, and Southern Africa. Over half of all gastric cancers occur in developing countries with the highest incidence in East Asia, South America (Andes Region), and Eastern Europe. Following migration to areas of lower risk, subsequent generations experience a risk approaching that of the surrounding population, implicating an important role for environmental factors on the development of gastric cancer. In the United States, there were estimated to be 17,990 new cases of esophageal cancer and 15,210 deaths in 2013. The estimated new cases and deaths of gastric cancer were 21,600 and 10,990, respectively (1). Advances in prevention, early detection, aggressive surgery, the use of adjuvant therapy, and more effective antineoplastic agents will hopefully reduce the incidence and improve survival.
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Esophageal
Gastric
Intestinal type (expanding): characterized by the formation of distinct glands, and typically involves the cardia, corpus, or antrum. It is often associated with multifocal (atrophic) gastritis and intestinal metaplasia of the antrum, as well as pernicious anemia, older age, male sex, and various environmental factors, including Helicobacter pylori. There has been a dramatic decrease in the incidence of this form of gastric cancer in developing countries.
Diffuse type (infiltrative): often presents as linitis plastica. It is characterized by poorly organized clusters or signet-ring cells (mucin containing). They often arise in the corpus and affect a generally young population. There is a propensity for these tumors to develop in patients with superficial gastritis related to H. pylori without atrophy or metaplasia, as well as those who have the type A blood group. Familial clusters are common. These tumors generally tend to be more aggressive than the intestinal type.
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Esophageal
Squamous cell: cigarette smoking, alcohol, achalasia, tylosis, caustic stricture (i.e., lye), prior radiation.
Adenocarcinoma: Barrett's esophagus due to GERD, smoking, obesity, higher socioeconomic class, Caucasian, male.
Gastric
Diets rich in salty or smoked foods, nitroso compounds, low in vegetable and antioxidants.
H. pylori infection, which is dependent on genotype and host factors (polymorphisms).
Smoking increases the risk by about 1.5-fold.
Atrophic gastritis increases the risk by nearly sixfold.
Prior gastric surgery with the highest risk at 15–20 years. The risk is greater following Billroth II than Billroth I anastomosis.
Ionizing radiation was associated with a relative risk of 3.7 in survivors of the Japanese atomic bomb.
Blood group A is associated with a 20% higher incidence.
Low-socioeconomic group results in an increase ...