Abstract
To evaluate the detectability of a miniature endoscopic ultrasonic probe (mini-EUS probe) in diagnosis of the invasivity of the superficial esophageal cancer, the pre-operative ultrasound studies by the mini-EUS probe were compared with the histological studies on resected specimens in a series of fifteen cases of the O-IIc type superficial esophageal cancer. From the analysis of the results, the author proposed the new criteria of ultrasonographic diagnosis as follows: (1) Type T (-): Tumorous echo cannot be detected clearly by the mini-EUS probe when the esophageal mucosa is adequately streched by de-aerated water. This type is considered to be m1-m2 superficial cancer. (2) Type T (+): If the lesion is detected as an abnormal ultrasonogenic structure when the esophageal mucosa is adequately streched, the invasivity is considered to be deeper than m 3 superficial cancer. (3) Type T (+) P: If the lesion is detected as a protruded echogenic structure when the esophageal wall is contracted, it suggests that the depth of the invasion is m3-sm1 superficial cancer. (4) Type T (+) F: If the lesion is detected as a rigid flat structure in contracted esophagus, sm2-sm3 invasion is highly suspected. In order to evaluate the efficacy of new diagnostic criteria, the author examined another series including sixteen cases of O-IIc type superficial esophageal cancer by mini-EUS. Microscopic study proved that the accurate diagnostic ratio was 87.5% (14/16). It is concluded that this new diagnostic criteria by the mini-EUS is useful in diagnosis of invasivity of the O-IIc type superficial esophageal cancer.
