Prospective evaluation of advanced molecular markers and imaging techniques in patients with indeterminate bile duct strictures. - Levy MJ; Baron TH; Clayton AC; Enders FB; Gostout CJ; Halling KC; Kipp BR; Petersen BT; Roberts LR; Rumalla A; Sebo TJ; Topazian MD; et al. (The American journal of gastroenterology, 2008)