based on these findings , we conclude ( a ) that there are at least two endoscopically distinct types of barrett 's esophagus involving the lower esophagus -- a circumferential type and an island type , ( b ) that both types are associated with chronic gastroesophageal reflux , with the island type being accompanied by less severe epithelial injury than the circumferential type , and ( c ) that the identification of dysplasia in the two types suggests that both are unstable lesions requiring continued surveillance with endoscopy and biopsy .
C0004763
barrett 's esophagus
C0014876
esophagus