Objectives: To evaluate the Ki-67 antigen expression in patients with Barrett’s esophagus and esophageal adenocarcinoma and to analyse its correlation with the metaplasia-esophageal adenocarcinoma progression.
Methods: Through imunohistochemical analysis we evaluated Ki-67 index in patients with Barrett’s esophagus, esophageal adenocarcinoma and controls, assisted at Hospital de Clinicas de Porto Alegre between 2002 and 2005. We included patients with endoscopically visible columnar mucosa of the distal esophagus, whose biopsy proved specialized intestinal type metaplasia, patients with esophageal and esophagogastric tumors type I and II and patients with histologically normal gastric mucosa (control).
Results: We studied 57 pacients. There was no statistically significant differences between the groups regarding age or race. Patients with cancer were predominantly men. Ki-67 index averaged 10±4% in patients with normal gastric mucosa (n=17), 21±15% in patients with Barrett’s esophagus (n=21) and 38±16% in patients with cancer (n=19). Ki-67 expression was significantly different between all groups (P<0,05). There was strong linear correlation between Ki-67 expression and metaplasia-adenocarcinoma sequence (P<0,01). In patients with cancer, Ki-67 was not associated with clinical or surgical staging.
Conclusions: Ki-67 antigen has increased expression along the metaplasia-adenocarcinoma sequence. There is strong linear correlation between Ki-67 proliferative activity and Barrett’s carcinogenesis.