 1.3. Protocol code: HEPACO 1.4. Principal Investigators: Dr. Candid Villanueva Sanchez. Dr. Jose Mateo Arranz. Contributors: Dr. Alicia Brotons Service of Digestive Pathology, Dr. Angela Puente service of Digestive Pathology, Dr. Isabel Graupera Service of Digestive Pathology and Dr. Marina Carrasco Hematology Service. Hospital de la Santa Creu i Sant Pau. Avgda. Sant Antoni Maria Claret, 167. 08025 Barcelona. Tel: 34 93 291 91 39. Fax: 34 93 291 92 78. 