Learning curve for endoscopic submucosal dissection of esophageal neoplasms

There is a significant learning curve for endoscopic submucosal dissection of esophageal neoplasms that has not been fully characterized. This retrospective study included 33 consecutive superficial esophageal neoplasms for analysis of the learning curve for esophageal endoscopic submucosal dissection based on a single, novice endoscopist's experience. The study was divided into three periods (T1, T2, and T3) of 10 endoscopic submucosal dissection procedures in chronological order, with 13 procedures in the last period. Patient factors (age, sex, coexistent esophageal varices, or submucosal fibrosis) and tumor factors (location at upper esophagus, involving >3/4 esophageal circumference) for endoscopic submucosal dissection were not statistically different between the periods. The mean procedure time was 74.6 min/cm(2) , 23.4 min/cm(2) , and 10.5 min/cm(2) for T1, T2, and T3, respectively. The procedure time decreased over time (P = 0.02) and post hoc test revealed significant difference was only between T3 and T1 (P = 0.019). The en bloc resection rate was 50%, 100%, and 92.3% for T1, T2, and T3, respectively (P for trend = 0.015). R0 resection rate was 40%, 100%, and 84.6% for T1, T2, and T3, respectively (P for trend = 0.023). Two patients had complications: each one patient in T1 and T3 period experienced major bleeding during the procedure (P for trend = 0.875). None of the patients had esophageal perforation. The results of the study concluded that at least 30 cases of endoscopic submucosal dissection of esophageal neoplasms are needed for a novice endoscopist to gain early proficiency in this technique.

A phase II study of endoscopic submucosal dissection for superficial esophageal neoplasms (KDOG 0901)

BACKGROUND

Most previous studies of endoscopic submucosal dissection (ESD) for superficial esophageal neoplasms were retrospective; prospective studies are scant.

OBJECTIVE

To prospectively assess the efficacy and safety of ESD for superficial esophageal neoplasms.

DESIGN

Phase II study.

SETTING

University hospital.

PATIENTS

Fifty-two patients (median age 68 years; 48 men) who had a histologic diagnosis of superficial esophageal cancer without metastasis on CT or high-grade intraepithelial neoplasia (HGIN) were enrolled from April 2009 through November 2011.

INTERVENTION

ESD was used to treat 56 lesions. All procedures were done by 4 endoscopists who each had previously performed ESD in more than 100 patients with gastric tumors.

MAIN OUTCOME MEASUREMENTS

The primary endpoint was the R0 resection rate, and secondary endpoints were the safety and the rate of accurately diagnosing tumor depth on endoscopic examination.

RESULTS

The median treatment time was 69 minutes (24-168 minutes). The histopathologic diagnosis was squamous cell carcinoma in 49 lesions, HGIN in 5, and tubular adenocarcinoma in 2. The en bloc resection rate and R0 resection rate were 100% and 94.6%, respectively. The rates of adverse events during ESD and after ESD were 22.2% and 53.8%, respectively, but most events were mild. One patient (1.9%) had mediastinal emphysema without perforation. The rate of accurately diagnosing tumor depth on endoscopic examination was 76.8%.

LIMITATIONS

Single-center, nonrandomized study.

CONCLUSION

Our study showed that ESD was an effective and relatively safe treatment for superficial esophageal neoplasms. ESD may be a useful treatment option for superficial esophageal neoplasms in hospitals with endoscopists who are experts in performing ESD for gastric tumors. (

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000002047.).