有馬 美和子

Miwako ARIMA

千葉大学医学部第2外科

Second Department of Surgery Chiba University School of Medicine

キーワード : Cardiac cancer, Endoscopic ultrasonography , Esophageal invasion , Operative method , Proximal invasion pattern

We analyzed images of the cardiac area obtained by linear array endoscopic ultrasonography (EUS), evaluated the proximal invasion pattern of cardiac cancer, and compared this pattern with histologic findings. The proximal patterns of cardiac cancer were classified into five types: type A, superficial type; type B; expansive type; type C, superficial infiltrating type; type D, deeply infiltrating type, and type E, diffusely infiltrating type. Relationships between the gross and EUS types of cancer: Type 4 was frequently observed in type E tumors, but no other associations were found. Histologically, types A and B tumors were frequently well-differentiated, while types D and E tumors were frequently poorly differentiated. EUS findings, however, closely reflected histologic images at the cancer front: infiltration of the m layer was frequently observed in type A, that of the m, sm and superficial layers in types B and C, that of the sm and deeper layers in tyape D, and that of all layers in type E. Endoscopic images in patients showing esophageal invasion were classified into 6 types: tumorous, ulcerative, erosive, fold, intramural metastatic, and unchanged. Even tumors of the same endoscopic type sometimes showed different EUS types. Distance of esophageal invasion was long in typesB, C, and E. Length of subepithelial esophageal invasion, representing invasion from the exposed cancer area through the subepithelial area, was longest in type E, followed in order by types D, C, B, and A. A significant difference was observed between type E (mean, 19.3 mm) and the other types. When the end of proximal resection is determined, a long ow is especially important in type E. EUS can visualize the EGJ, foramen of the vena cava, crus, and His angle. The proximal tip of the crus visualized in EUS images of the aorta can be recognized as a hiatus, a border between the mediastinum and the abdomen. Looking at the relationship between the proximal end of cancer and the hiatus, we found 2 cm (mean) of esophageal invasion when a cancer had reached the hiatus. Twenty-eight of 33 patients in whom the proximal end of cancer had reached the hiatus or extended beyond it received thoracotomy. Four of 6 patients showing ow (+) had type E. The hiatus in EUS images can thus be a landmark for selecting thoracotomy. In type E, a long ow is necessary to avoid ow (+).