RESUMEN
OBJECTIVE: to determine the diagnostic precision of endoscopic ultrasounds (EUS) and magnetic resonance imaging (MRI) in the preoperative staging of gastric cancer. METHODS: a prospective, blind study was carried out in 17 patients diagnosed with gastric cancer (GC) using endoscopic biopsy from November 2002 to June 2003. Patients underwent preoperative MRI and EUS. The reference test used was pathology, and laparotomy for non-resectable cases. RESULTS: MRI (53%) was better than EUS in the assessment of gastric wall infiltration (35%). MRI (50%) was also superior to EUS (42%) for N staging. After pooling stages T1-T2 and T3-T4 together, results improved for both MRI (67 and 87.5%, respectively) and EUS (67 and 62.5%, respectively) (p < 0.05). N staging--lymph node invasion--results were correct in 50% for MRI as compared to EUS (42%). In classifying positive and negative lymph nodes EUS was superior to MRI (73 versus 54%). CONCLUSIONS: MRI was the best method in the assessment of gastric wall infiltration. EUS was superior to MRI for T1 staging, and in the assessment of lymph node infiltration.