Prevention of Esophageal CancerDoctors cannot always explain why one person gets cancer and another does not. However, scientists have studied general patterns of cancer in the population to learn what things may increase our chance of developing cancer.
Anything that increases a person's chance of developing a disease is called a risk factor. Anything that decreases a person's chance of developing a disease is called a protective factor. Some of the risk factors for cancer can be avoided, but many cannot. For example, while you can choose to quit smoking, you cannot choose which genes you have inherited from your parents. Both smoking and inheriting specific genes could be considered risk factors for certain kinds of cancer, but only smoking can be avoided. Prevention means avoiding the risk factors and increasing the protective factors that are under your control.
It is important to remember that while risk factors for cancer should be avoided, this isn't a guarantee that you will not get cancer. Many people with a particular risk factor for cancer do not get the disease, but some people are more sensitive than others to the factors that can cause cancer. It is important to talk to your doctor about ways you can prevent cancer that might be effective for you.
Incidence and Mortality of Esophageal CancerAnnually, approximately 14,250 Americans will be diagnosed with esophageal cancer, and 13,300 will die of this malignancy. Of the new cases, 10,860 will occur in men and 3,390 will occur in women.
Two histological types account for the majority of malignant esophageal neoplasms, i.e., adenocarcinoma and squamous carcinoma. The epidemiology of these types varies markedly. In the 1960s, squamous cell cancers comprised over 90% of all esophageal tumors. The incidence of esophageal adenocarcinomas has risen markedly over the past 2 decades, such that it is now more prevalent than squamous cell cancer in the United States and Western Europe, with most tumors located in the distal esophagus. Although the overall incidence of squamous cell carcinoma of the esophagus is declining, this histologic type remains 6 times more likely to occur in black males than in white males. Incidence rates generally increase with age in all racial/ethnic groups. In black men, however, the incidence rate for the 55 to 69 year age group is close to that of whites in the 70 years and older age group. In black women, aged 55 to 69 years, the incidence rate is slightly higher than that of white women in the 70 years and older age group.
Risk Factors for Esophageal CancerWhile risk factors for squamous cell carcinoma of the esophagus have been identified (such as tobacco use, alcoholism, malnutrition, infection with human papillomavirus), the risk factors associated with esophageal adenocarcinoma are less well defined. The most important epidemiological difference between squamous cell cancer and adenocarcinoma, however, is the strong association between gastroesophageal reflux disease (GERD) and adenocarcinoma. The results of a population-based case controlled study suggest that symptomatic gastroesophageal reflux is a risk factor for esophageal adenocarcinoma. The frequency, severity, and duration of reflux symptoms were positively associated with increased risk of esophageal adenocarcinoma.
An interesting hypothesis relates the rise in the incidence of esophageal adenocarcinoma to a declining prevalence of Helicobacter pylori infection in Western countries. Reports have suggested that gastric infection with H. pylori may protect the esophagus from GERD and its complications. According to this theory, H. pylori infections that cause pangastritis also cause a decrease in gastric acid production that protects against GERD. Patients whose duodenal ulcers were treated successfully with antibiotics developed reflux esophagitis twice as often as those in whom infection persisted. Other factors that have been suggested to explain the increased risk of esophageal adenocarcinoma include obesity and use of medications, such as anticholinergics, that can predispose to GERD by relaxing the lower esophageal sphincter.
GERD is a risk factor for esophageal adenocarcinoma because long-standing GERD is associated with Barretts esophagus, the condition in which an abnormal intestinal epithelium replaces the stratified squamous epithelium that normally lines the distal esophagus. The intestinal-type epithelium of Barretts esophagus has a characteristic endoscopic appearance that differs from squamous epithelium. Dysplasia in Barretts epithelium represents a neoplastic alteration of the columnar epithelium that may progress to invasive adenocarcinoma.
Lightdale, M.D., Charles J.. "Esophageal Cancer." Vol. 94, No. 1, 1999. The American Journal of Gastroenterology. http://www.acg.gi.org/physicians/guidelines/EsophagealCancer.pdf
"What You Need to Know About Cancer of the Esophagus - Esophageal Cancer Prevention." National Cancer Institute. http://www.cancer.gov/cancertopics/pdq/prevention/esophageal/Patient/page2