[1] Univ Siena, Policlin Santa Maria alle Scotte, Unita Operat Chirurgia Gen & Oncol, Sect Gen Surg & Surg Oncol, I-53100 Siena, Italy
[2] Univ Siena, Policlin Santa Maria alle Scotte, Sect Human Pathol, Dept Human Pathol & Oncol, I-53100 Siena, Italy