[1] USC Norris Comprehens Canc Ctr, Los Angeles, CA USA
[2] Azienda Osped Univ Pisana, UO Oncol Med 2, Pisa, Italy
[3] Azienda Osped Univ Pisana, UO Oncol Med 2, Ist Toscano Tumori, Pisa, Italy
[4] Canc Inst Hosp, Div Gastroenterol Surg, Gastroenterol Ctr, Tokyo, Japan
[5] Canc Inst Hosp, Dept Surg Gastroenterol, Gastroenterol Ctr, Tokyo, Japan
[6] JFCR, Canc Inst Hosp, Dept Gastroenterol, Tokyo, Japan