Clinical outcome of endoscopic mucosal resection for superficial GI lesions and the role of high-frequency US probe sonography in an American population

Background: Endoscopic mucosal resection, a major advance in endoscopy, provides an endoscopic option for management of focal and superficial lesions of the gastrointestinal tract. Although popular in the Orient due to the high incidence of superficial neoplasia, there are scant data on its use in the United States. Our aim was to assess the efficacy and safety of endoscopic mucosal resection in our patient population and evaluate whether high-frequency ultrasound (US) probe sonography provides useful information relative to the procedure. Methods: Endoscopic mucosal resection was performed in 32 of 33 patients referred for endoscopic management of superficial neoplastic or submucosal lesions. High-frequency US probe sonography was performed with a 20 MHz US probe. Endoscopic mucosal resection was performed after submucosal saline solution injection with the strip biopsy technique. Results: Thirty-two superficial lesions were resected, Of 24 epithelial lesions resected, 22 were intramucosal and 2 had early submucosal invasion (SM1); the 2 patients with the latter 2 lesions were poor candidates for surgery. Depth of penetration of 25 of 26 lesions scanned was accurately predicted by high-frequency US probe sonography. Eight lesions raised from the submucosa, Minor complications were limited to the colon. Of the 7 patients with carcinomas, 6 had no evidence of recurrence at a mean follow-up of 12 months; 1 died of a second primary cancer. Conclusions: Endoscopic mucosal resection provided definitive therapy for 24 early-stage neoplastic lesions and provided a diagnosis in the remaining 8, In our study, the technique proved to be safe with only three minor complications noted. High-frequency US probe sonography accurately delineated the depth of penetration of all lesions scanned, therefore making it an ideal imaging modality for selecting patients who may benefit from endoscopic mucosal resection.