1. HIV and STD Unit (Infectious Disease Service) Bellvitge University Hospital/Bellvitge Biomedical Research Institute (IDIBELL) L'Hospitalet de Llobregat Barcelona Spain
2. Pathology Unit Bellvitge University Hospital/IDIBELL L'Hospitalet de Llobregat Barcelona Spain
3. Colorectal Unit, General and Digestive Surgery Department Bellvitge University Hospital/IDIBELL L'Hospitalet de Llobregat Barcelona Spain
4. Infection and Cancer Laboratory Cancer Epidemiology Research Program Catalan Institute of Oncology (ICO)/IDIBELL L'Hospitalet de Llobregat Barcelona Spain
5. CIBERen Epidemiología y Salud Pública CIBERESP Madrid Spain
6. Clinical Research Support Unit Clinical Pharmacology Department Bellvitge University Hospital/IDIBELL L'Hospitalet de Llobregat Barcelona Spain