Endoscopic partial resection with the unroofing technique for reliable tissue diagnosis of upper GI subepithelial tumors originating from the muscularis propria on EUS (with video)
Received 23 May 2009; accepted 19 July 2009. published online 02 November 2009.
Background
There is a growing body of evidence that a pathological diagnosis is necessary for small (<3 cm in diameter), asymptomatic, hypoechoic, subepithelial tumors (SETs) originating from the muscularis propria on EUS. However, the diagnostic efficacy of current tissue sampling techniques appears to be limited.
Objective
To evaluate the diagnostic yield and safety of endoscopic partial resection using the unroofing technique (EPR-UT) in a subset of patients.
Design
A prospective case series.
Setting
A single tertiary-care referral center.
Patients
Between August 2007 and March 2009, 16 patients with hypoechoic SETs of <3 cm in diameter, originating from the muscularis propria on EUS (14 gastric and 2 esophageal lesions), underwent EPR-UT.
Interventions
The overlying mucosa was removed by using the unroofing technique using a conventional snare with electrical current to expose the tumor sufficiently. Next, the exposed tumor was partially resected by snaring.
Main Outcome Measurements
The diagnostic yield and safety of this method.
Results
EPR-UT provided specimens that were sufficient for a diagnosis and the assessment of risk for malignancy in 15 out of 16 cases (diagnostic yield 93.7% [95% CI, 80.4%-100.0%]). The pathological diagnoses were leiomyoma (7 of 15, 46.6%), GI stromal tumor (6 of 15, 40.0%), aberrant pancreas (1 of 15, 6.6%), and well-differentiated neuroendocrine carcinoma (1 of 15, 6.6%). Six cases with GI stromal tumor were classified as very low risk for malignant potential (mitotic index <5/50 high-power fields). Procedural blood oozing was relatively common (9 of 16, 56.0% [95% CI, 33.0%-77.0%]); however, this minor complication was easily controlled by argon plasma coagulation. There were no procedure-related major complications (0 of 16, 0% [95% CI, 0.0%-23.0%]).
Limitations
Single-center, noncomparative study with small sample size.
Conclusion
EPR-UT appears to be simple, safe, and effective for determining the definite pathological diagnosis and assessing malignant potential of small, hypoechoic SETs originating from the muscularis propria on EUS.
Current affiliations: Division of Gastroenterology, Departments of Internal Medicine (C.K.L., I-K.C., S-H.L., S.H.L., T.H.L., S-H.P., H-S.K., S-J.K.) and Pathology (H-D.C.), Soon Chun Hyang University College of Medicine, Cheonan Hospital, Cheonan, Korea
Reprint requests: Il-Kwun Chung, MD, Division of Gastroenterology, Department of Internal Medicine, Soon Chun Hyang University College of Medicine, Cheonan Hospital, 23-20 Bongmyung-dong, Cheonan, Choongnam, 330-721, Korea.
DISCLOSURE: All authors disclosed no financial relationships relevant to this publication.
ABSTRACT
Endoscopic partial resection with the unroofing technique for reliable tissue diagnosis of upper GI subepithelial tumors originating from the muscularis propria on EUS (with video)