GSTM1 and carcinoma of the ampulla of vater: The purpose of this investigation was to assess the prognostic importance of the combination of preoperative hemoglobin (Hb) levels and Geriatric Nutritional Risk Index (GNRI) in forecasting postoperative survival outcomes for patients undergoing pancreaticoduodenectomy (PD) due to Vater ampulla carcinoma (VPC).