1. Most esophageal cancers are: Answer adenocarcinomas -arise from glands lining esophagus -resemble cancers of stomach and small intestine 2. The cause of esophageal cancer is: Answer unknown but there are key risk factorswhich include: -Barret's esophagus -Smoking -Excess alcohol use -obesity -History of achlasia -Increased incidence with age -Increased incidence with non-hispanic white men and alaska natives -incidence higher in men than in women 3. Majority of tumors are located in: Answer middle and lower portions of esophagus 4. Malignant tumors will usually appear as: Answer ulcerate lesion -may penetrate muscular layer and outside wall of esophagus -obstruction in later stages 5. Achlasia is a condition marked by: Answer delayed emptying of the lower esophagus associated with squamous cancer