Data on 1248 cases of stomaches radically operated on for cancer at the surgical departments of the Moscow Regional Research Clinical Institute in 1971 to 2000 were used to study a number of problems associated with cancer of the upper stomach, by regarding the present-day role of radiation diagnosis as of paramount importance. The following radiation diagnostic techniques were assessed. Among them there were traditional X-ray studies (in each case), the new radiation diagnostic techniques: ultrasound study and computed tomography (CT) (750 studies), magnetic resonance imaging (MRI) (120 studies). The potentialities of radiation diagnosis and endoscopy performed in all cases are compared. A specially developed procedure for exploring endophytic forms of gastric cancer was employed in the morphological studies of the material. The incidence of cancer of the upper stomach and its association with the esophagus are presented; some aspects of the morphogenesis of cancer of this site are discussed. The relationship of its clinical symptoms and its radiation image has been studied. In the authors' opinion, the past two decades' rise in the incidence of proximal gastric cancer is one of the main problems in diagnosing gastric cancer that continues holding its stand in the general structure of cancer morbidity. The tendency for diffuse and mixed forms to increase in the morphogenesis of gastric cancer provides evidence that radiation techniques should be actively used in its diagnosis. It is necessary to apply classical double-contrasting X-ray study and endoscopy on equal grounds as basic diagnostic methods at early stages. Only their concord use may change the poor situation associated with the diagnosis of cancer at this site. CT and MRI as additional techniques may substantially provide more required diagnostic information. This is first and foremost associated with difficulties in gastric endoscopic study when esophageal cancer is apparently proved.