Diagnosis of simultaneous multiple gastric cancers by the endoscopic Congo red--methylene blue test.

The clinicopathological features of simultaneous multiple gastric cancers, and the accuracy of their diagnosis by routine endoscopic examination were analyzed. In addition, the accuracies of diagnosis of coexisting early gastric cancers by routine endoscopic examination and by the endoscopic Congo red--methylene blue test developed in our hospital were compared. The results showed that multiple cancers occurred frequently in elderly male patients, in patients with early gastric cancer of the flat and elevated types and the depressed type without converging folds, and in patients with advanced cancer of Borrmann type I. These patients frequently have early cancers of the flat or depressed types without converging folds, and advanced cancers of Borrmann type I. The coexisting lesions are very difficult to diagnose by routine endoscopic examination: a correct diagnosis of coexisting early cancers was made in only 28.3% of the cases by routine endoscopic examination. But with the Congo red--methylene blue test, the diagnostic rate was raised significantly to 88.9%. In this test, Congo red and methylene blue are sprayed on the surface of the stomach and are bleached within 2 to 5 minutes on the surface of a tumor, but not on the surface of unaffected mucosa.