1 Department of Internal Medicine, Hospital of Laredo, Avda Derechos Humanos s/n, 39770 Laredo, Cantabria, Spain. Electronic address: miguel.carrascosa@scsalud.es.
2 Department of Internal Medicine, Gastroenterology Section, Hospital of Laredo, Avda Derechos Humanos s/n, 39770 Laredo, Cantabria, Spain.
3 Department of Surgery, Section of Hepatobiliary and Pancreatic Surgery, University Hospital Marqués de Valdecilla, Avda Valdecilla s/n, 39008 Santander, Cantabria, Spain.
4 Department of Internal Medicine, Hospital of Laredo, Avda Derechos Humanos s/n, 39770 Laredo, Cantabria, Spain.
5 Molecular Biology Laboratory, Service of Pathology, University Hospital Marqués de Valdecilla, Faculty of Medicine, Avda Valdecilla s/n, 39008 Santander, Cantabria, Spain.