Preoperative lymphocyte count as a prognostic factor in resected pancreatic ductal adenocarcinoma

Background and aims. Recognized prognostic factors for resected pancreatic ductal adenocarcinoma (PDAC) include tumour size, differentiation, resection margin involvement and lymph node metastases. A further prognostic factor of less certain significance is lymphocyte count. The aim of this study was to investigate whether preoperative lymphocyte count is a prognostic indicator in patients with PDAC. Material and methods. Patients who had undergone a potentially curative pancreaticoduodenectomy (PD) for PDAC between 1998 and 2005 were analysed. Standard prognostic factors, preoperative lymphocyte count, preoperative neutrophil count and survival data were collected. Results. Of the 44 patients studied, univariate analysis identified predictors of a poor survival as lymph node status (node positive (+ve) 10.3 [5.4-20.9] months versus node negative (−ve) 14.2 [10.9-31.4] months; p=0.038), posterior resection margin invasion (margin +ve 7.0 [5.1-15.0] months versus margin −ve 13.1 [10.0-28.3] months; p=0.025) and lymphocyte count below the reference range (<1.5×109/litre 8.8 [7.0-13.1] months versus ≥1.5×109/litre 14.3 [7.0-28.3] months; p=0.029). Low preoperative lymphocyte count (p=0.027) and posterior margin invasion (p=0.023) retained significance on multivariate analysis. Preoperative neutrophil to lymphocyte ratio was not a significant prognostic factor. Conclusion. Preoperative lymphocyte count is a significant prognostic factor in patients with PDAC.