Therapeutic endoscopy pushing the boundaries: what boundaries?

Department of Medicine, Maimonides Medical Center, Professor Emeritus, Johns Hopkins University School of Medicine, Brooklyn, New York, USA Correspondence to Anthony N. Kalloo, Chairman, Department of Medicine, Maimonides Medical Center, Professor Emeritus, Johns Hopkins University School of medicine, 4802 Tenth Avenue, Brooklyn, NY 11219, USA. Tel: +1 718 283 6516; fax: +1 718 283 8498; e-mail: [email protected]