Abstract
The clinical evaluation of endoscopic ultrasonography (EUS) in the diagnosis of submucosal tumor (SMT) in the upper digestive tract is discussed in this paper. EUS was carried out in 45 patients with submucosal tumor and 31 patients with submucosal tumorous lesion compressed by extracanal organs. The differential diagnosis between SMT and tumorous compression was accomplished without error using this method. All the cases of submucosal tumors were easily detected, even if their size was smaller than 5 mm in diameter. Furthermore, it was possible to detect which layer had SMT in the 5 layer structure of the digestive tract wall revealed by ultrasound, and the size of SMT shown by EUS was in good correspondence with the resected material. The diagnosis of leiomyoma and/or leiomyosarcoma was determined by detecting the origin in the mucosal muscle layer or the proper muscle layer ; however, it was hard to make a distinction between these two diseases through EUS findings. Differential diagnosis of SMT in the submucosal layer was possible by analysing echogenicity and echo pattern. A cyst with a hypoechoic mass, an aberrant pancreas with echogenicity intermediate between the echo-level of the sm layer and that of the pm layer, and a lipoma with a hyperechoic mass were detectable by EUS ultrasonogram. The extracanal compressions by other organs and lesions were also shown by EUS. Thus, the ability to delineate the submucosal tumors by using echo-endoscope was evaluated as the most useful method among the conventional body-imaging diagnostics.
