[1] Hosp Arnau Vilanova, Serv Cirugia Gen & Aparato Digest, Lleida, Spain
[2] Hosp Univ Ramon y Cajal, Serv Cirugia Gen & Aparato Digest, Madrid, Spain
[3] Hosp Univ Ramon y Cajal Madrid, Serv Cirugia Gen & Aparato Digest, Secc Cirugia Endocrina Mama Sarcoma & Melanoma, Madrid, Spain
[4] Hosp Univ La Paz, Serv Cirugia Gen & Aparato Digest, Unidad Cirugia Endocrina & Cirugia Mama, Madrid, Spain