Esophageal Cancer: Current Diagnosis and Management
Journal of Clinical Outcomes Management. 2014 August;21(8)
References
) [10,11].
While GERD is the most common cause of esophageal adenocarcinoma, other important causes/risk factors have been identified such as male sex, Caucasian race, older age, and obesity [8,12].In a prospective study by Abnet et al, patients who had a body mass index (BMI) greater than 35 kg/m 2 had a significantly increased risk of esophageal adenocarcinoma when compared to patients with a BMI of 18.5 to 25 kg/m 2 (hazard ratio [HR], 2.27; 95% CI, 1.44 to 3.59) [13]. Similarly, a recent meta-analysis found that patients with a BMI of 30 kg/m 2 or greater had a relative risk for esophageal adenocarcinoma of 2.71 (95% CI, 2.16 to 3.46) [14]. Despite the strong correlation, the etiology of esophageal adenocarcinoma is complex and cannot be fully explained by obesity trends [15].
Smoking is another important risk factor associated with the development of esophageal adenocarcinoma. A study from the Barrett’s and Esophageal Adenocarcinoma Consortium revealed strong associations with esophageal adenocarcinoma and cigarette smoking (OR, 1.96; 95% CI, 1.64 to 2.34) [16]. Furthermore, the study found a statistically significant dose-response association between cigarette smoking and esophageal adenocarcinoma ( P < 0.001).
Finally, dietary intake of vegetables and fruits has been shown to reduce the risk of Barrett’s esophagus. In a case-control study, patients with a median intake of 8.3 servings per day of vegetables and fruits had a 73% lower risk of developing Barrett’s esophagus versus those with 2.0 servings per day (OR, 0.27; 95% CI, 0.15 to 0.50) [17]. Each additional serving of vegetables and fruit was associated with a 14% reduction of risk (OR, 0.86; 95% CI, 0.80 to 0.93).
Esophageal Squamous Cell Carcinoma
In the United States, increased alcohol intake and use of tobacco products are the major risk factors for the development of esophageal SCC ( Figure 2 ). A prospective study by Freedman and colleagues demonstrated significant associations between alcohol intake and esophageal SCC in the U.S. population [18]. The study found that patients who drink more than 3 alcoholic drinks per day have an increased risk of developing esophageal SCC (HR, 4.93; 95% CI, 2.69 to 9.03). When compared to nondrinkers, however, patients who drink up to 1 alcoholic drink a day have a decreased risk of developing esophageal SCC (HR, 2.06; 95% CI, 1.16 to 3.68).Likewise, a study by Pandeya et al showed there was no significant association with alcohol consumption less than 170 g per week, although above that amount there was a significant linear correlation with alcohol and esophageal SCC (OR, 1.03; 95% CI, 1.02 to 1.05 per 10 g of alcohol per week) [19].
In the study by Freedman et al, when compared with nonsmokers, current cigarette smokers were at significantly increased risk for esophageal SCC (HR, 9.27; 95% CI, 4.04 to 21.29) [18].Smoking has a stronger correlation with esophageal SCC than with esophageal adenocarcinoma [20]. In current smokers, the risk for developing esophageal SCC increases approximately three- to sevenfold [20]. The duration and intensity of smoking has been shown to increase the risk of esophageal SCC as well [21]. Smoking cessation has been shown to reduce the risk of esophageal SCC, but data shows that former cigarette smokers still are at a significant risk [18,21]. In a population-based case-control study, the risk of esophageal SCC in ex-smokers remained elevated for up to 30 years (OR, 1.44; 95% CI, 0.82 to 2.52) [21]. There are only limited studies that have examined the relationship between esophageal SCC and smokeless tobacco and other smoking products. Despite the limited number of studies, smokeless tobacco has been associated with esophageal SCC [22]. In a 2012 study of patients from India, chewing nass (a mix of tobacco, ash, oil, lime, and coloring and flavoring agents) and smoking hookah were associated with an increased risk of developing esophageal SCC [23].
