Esophageal Leiomyoma Originating in the Muscularis Propria Layer Resected by Endoscopic Submucosal Dissection
Korean Journal of Gastroenterology
Case: A 51-year-old woman without specific symptoms received a routine endoscopy during a regular checkup. The results showed a subepithelial tumor (SET) located 23 cm from the central incisors (Fig. 1A) . Endoscopic ultrasound (EUS) demonstrated a 2.5 cm sized homogeneous hypoechoic tumor originating in the muscularis propria layer (Fig. 1B) . Endoscopic submucosal dissection (ESD) was performed in the following manner ( Fig. 1C -G). After obtaining informed consent ESD was performed using a
... performed using a standard single-channel endoscope (GIF-H260Z; Olympus, Tokyo, Japan) with a transparent cap (D-201-10704; Olympus, Tokyo, Japan). Approximately 5 mL of epinephrine in hypertonic saline (dilution 1:100,000) was injected into the submucosal layer. Next, the overlying mucosa was stripped away with a cauterizing wire snare. The snare was placed around the base of the tumor and tightened to excise the covering mucosa via electrocoagulation with a blended current. Once the mucosal layer was removed from the tumor, the underlying submucosal layer was removed from the tumor using an IT-knife. A whitish tumor was then identified in the separated submucosal layer. The exposed tumor was removed from the muscularis propria layer using an IT-knife. After completely resecting the tumor, the wound was evaluated carefully to identify any residual tumors. The specimens were fixed in formalin and embedded in paraffin blocks. The pathologic examinations included identification of cell type, overall cellularity, nuclear atypia, immunohistochemical findings, and the mitotic index. The mitotic index was determined with 50 consecutive high-power fields. Immunohistochemical analysis of CD117 (c-kit), CD34, smooth muscle actin, S-100, and Ki-67 markers was performed to differentiate tumors with mesenchymal origin. Two experienced pathologists confirmed the pathological diagnosis. After the procedure, proton pump inhibitors and antiulcer drugs were administered, and oral diet was suspended for 1 day. On the second postoperative day, the patient, without complications such as bleeding or pneumoperitoneum, was given a full liquid diet. The size of the resected tumor was 25 mm (Fig. 1H) , and the histopathologic diagnosis of the specimen was leiomyoma (Fig. 2) . The specimen showed both lateral and vertical tumor-free margins. We did not observe any residual tumors or recurrence during the follow-up period of 74 months.