[1] Univ Crete, Univ Hosp Heraklion, Sch Med, Dept Gen Surg, Iraklion, Crete, Greece
[2] Univ Crete, Sch Med, Lab Biostat, Iraklion, Crete, Greece
[3] Univ Crete, Univ Hosp Heraklion, Sch Med, Dept Surg Oncol, Iraklion, Crete, Greece
[4] Univ Patras, Univ Gen Hosp Patras, Sch Med, Dept Surg, Patras, Greece
[5] Univ Cyprus, Gen Hosp Nicosia, Sch Med, Dept Surg, Nicosia, Cyprus
[6] Natl & Kapodistrian Univ Athens, Laikon Gen Hosp, Dept Surg 1, Athens, Greece
[7] Natl & Kapodistrian Univ Athens, Laikon Gen Hosp, Propaedeut Dept Surg 2, Athens, Greece
[8] Univ Athens, Univ Gen Hosp Attikon, Sch Med, Dept Surg, Athens, Greece
[9] Gen Hosp Volos, Dept Surg, Volos, Greece
[10] Gen Hosp Trikala, Dept Surg, Trikala, Greece
[11] Univ Hosp Ioannina, Dept Surg, Ioannina, Greece
[12] Aristotle Univ Thessaloniki, Ippokrateio Gen Hosp Thessaloniki, Sch Med, Dept Surg, Thessaloniki, Greece
[13] Evangelismos Gen Hosp, Dept Surg 2, Athens, Greece
[14] Univ Thrace, Univ Gen Hosp Alexandroupolis, Sch Med, Dept Surg, Alexandroupolis, Greece
[15] Univ Hosp Crete, Dept Gen Surg, Iraklion 71110, Greece