[1] Nuovo Regina Margherita Hosp, Dept Gastroenterol & Digest Endoscopy, I-00153 Rome, Italy
[2] Univ Roma La Sapienza, S Maria Goretti Hosp, Oncol Unit, I-00185 Rome, Italy
[3] Riuniti Hosp, Gastroenterol Unit, Foggia, Italy
[4] Univ Bologna, Dept Internal Med & Gastroenterol, Bologna, Italy
[5] Miraca Life Sci, Miraca Res Inst, Irving, TX USA
[6] Univ Texas SW Med Ctr Dallas, Dept Pathol, Dallas, TX 75390 USA
[7] Univ Texas SW Med Ctr Dallas, Dept Med Gastroenterol, Dallas, TX 75390 USA