Novel endoscopic therapies for gastrointestinal malignancies: endoscopic mucosal resection and endoscopic ablation.

Gastrointestinal malignancies are often detected at advanced stages when the prognosis is poor. Screening guidelines that vary accord-ing to the regional disease prevalence are needed. High-resolution endoscopy, magnification endoscopy, chromoendoscopy, light autofluorescence endoscopy, and optical coherence tomography are new technologies designed to improve endoscopic detection. Once detected, lesions must be accurately staged, including depth of mucosal penetration and lymph node involvement, to determine endoscopic resectability. Widely applicable, relatively safe, and minimally invasive alternatives to surgery are needed. Endoscopic mucosal resection and endoscopic ablation are potentially curative for malignancies limited to the mucosa, obviating the need for surgery in these patients.