| Popis: |
Screening can improve survival for many individuals with premalignant or malignant lesions, particularly those of the gastrointestinal system. The aim of this chapter is to provide a comprehensive review of the most up-to-date recommendations and screening practices for the major cancers of the gastrointestinal system. Each section is formatted to describe the epidemiology, risk factors, screening methods, and recommendations pertaining to each gastrointestinal malignancy. There are no established screening guidelines for esophageal cancer, either squamous cell cancer (SCC) or esophageal adenocarcinoma (EAC), in the general population. However, there are recommendations to screen individuals with risk factors for Barrett’s esophagus (BE), and hence EAC, and to continue surveillance protocols in those identified with BE. While there are no guidelines for screening for gastric cancer in the United States given the low incidence of the disease, screening is recommended via upper endoscopy or upper GI series in Japan and Korea given the much higher prevalence of gastric cancer in this population. For colorectal cancer (CRC), which is the most widely screened disease of all the GI malignancies, screening is recommended for average-risk patients starting at age 50 and up to age 75 or until life expectancy is less than 10 years, with a variety of modalities including fecal-based tests, such as fecal occult blood test (FOBT), and endoscopic procedures, such as sigmoidoscopy or, most commonly, colonoscopy. For those at high risk for CRC, periodic screening with colonoscopy is recommended, usually with an earlier starting age and shorter intervals than in the average-risk population. In individuals at high risk for hepatocellular carcinoma, which includes those with chronic hepatitis B infection and those with cirrhosis, current recommendations are to screen via periodic ultrasonography. For pancreatic cancer, screening is not recommended in average-risk individuals. Screening of high-risk individuals remains controversial. |
