<prompt> Repeat upper GI endoscopy in a patient with a gastric ulcer is performed after how many weeks of PPI therapy to assess the healing of the ulcer and confirm absence of malignancy:2 weeks4 weeks6 weeks12 weeks  <response>: Repeat upper endoscopy is done in patients with a gastric ulcer after 6 to 10 weeks of acid suppressive therapy to confirm healing of the ulcer and absence of malignancy. 2 to 4 of repeat upper endoscopies have been repoed to disclose gastric cancer. Ref: Sleisenger and Fordtrans, E-9, P-305 