Traditional Xray Investigations

With the introduction of contrast media, which help to visualize the alimentary tract without inflicting any damage on the patient, the classical X-ray examination became the leading method for diagnosing gastric cancer. Gastroenterology was qualified as a relatively independent branch in medicine, and by the i96os-i97os it had accumulated vast experience in the diagnosis of gastric cancer. A group of experienced radiologists emerged who mastered the X-ray examination of the stomach. A roentgenosemi-otics of gastric cancer was then compiled; some of the signs remain valid today, but some require reevaluation.

Unfortunately, the indisputable successes of X-ray methods achieved in gastroenterology led to the erroneous belief that these methods had reached their climax. Some researchers in the 1960s declared that the effectiveness of the X-ray investigation in diagnosing gastric cancer was 95-98%. This statement was not valid, because the statistical data were based on experience at specialized hospitals, to which patients were admitted long after the appearance of their first complaints; in other words, these patients had far advanced forms of cancer.

It is easy to understand why endoscopic study of the gastric mucosa was regarded by physicians as the gold standard for the diagnosis of gastric cancer. The visualization of ulcers and the possibility of taking tissue specimens for morphological examination proved to be advantageous in the diagnosis of gastrointestinal pathologies [90, 232]. All these factors accounted for the endoscopic boom. But as time passed, many things became clearer. While it provides objective information on changes in the mu-cosal surface, endoscopy has limitations in estimating organic changes of the stomach wall on the whole (O Fig. 28).

About 40 years have passed since endoscopy was introduced into practical gastroenterology, but the diagnosis of gastric cancer has not improved. On the contrary, it has worsened somewhat. Diagnosis of minor cancers has remained at the same low level. The majority of patients who are admitted to specialized hospitals have cancer in far advanced forms. Physicians seem to underestimate endophytic cancer of the stomach, which is characterized by intramural growth, and to overestimate the diagnostic potentials of endoscopy. The extent of intramural infiltration in diffuse cancer proved to be more significant than it was possible to estimate by means of endoscopy [24]. Methods were then proposed for taking tissue specimens from deep layers of the stomach wall. First, however, one must know where exactly a tissue specimen should be taken and, second, endoscopic biopsy carries the danger of stomach perforation. It then became clear that X-ray methods must be restored to their important position in gas-troenterology.

Like any science, radiology continues to develop. Its potentials have been strengthened by such advanced technologies as ultrasonography, CT, MRI, and digital X-ray methods. As information on the advanced working method was accumulated, it turned out that gastroenterology, despite its vast and

▲ Fig. 28 a.

long experience, entails a contradiction. On the one hand, there is a huge amount of knowledge in gas-troenterology, which was accumulated over a period of almost 100 years and is used now in daily practice. On the other hand, the old methodological approaches to the diagnosis of pathologies and the original roentgenosemiotics continue to be employed mechanically and without reflection under changed conditions. True, there have been some positive shifts in organizational and methodological aspects, such as the examination of risk groups using X-ray fluoroscopy and digital X-ray spot imaging with subsequent target endoscopy. But interpretation of the findings (roentgenosemiotics) should be revised and corrected in the light of current concepts in morphology of gastric cancer [40, 67].

A comparative analysis of morphological estimates of infiltrative cancer conducted early in the twentieth century and today shows significant differences in how the essence of the problem is understood. Thus, at the present time, we observe a tendency toward compartmentalization of the pathological process, consisting in the artificial differentiation of tumors depending on the prevalence of particular signs, which sometimes are far from being equivalent. Meanwhile, according to some re-

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