Prognostic model for survival based on readily available pretreatment factors in patients with advanced pancreatic cancer receiving palliative chemotherapy.

Abstract

We aimed to construct a prognostic model to predict survival in patients with advanced pancreatic cancer (APC) receiving palliative chemotherapy using readily available pretreatment factors. The model was constructed using data from 306 consecutive patients with APC who received palliative chemotherapy between January 2006 and March 2013. The predictive accuracy of the model was assessed using a concordance index (c-index) and calibration curves. Among the 12 potential prognostic factors investigated, multivariate analysis identified the following six independent negative prognostic factors-performance status (PS), the presence of distant metastatic disease, the status of initially unresectable disease, carcinoembryonic antigen (CEA) level, carbohydrate antigen 19-9 (CA19-9) level, and neutrophil-lymphocyte ratio (NLR). A prognostic index (PI) based on the coefficients of these factors was constructed as follows-PI = 2 (if PS 2-3) + 1 (if distant metastatic disease) + 1 (if initially unresectable disease) + 1 (if CEA level ≥5.0 ng/ml) + 1 (if CA 19-9 level ≥1,000 U/ml) + 2 (if NLR ≥5). The patients were classified into three prognostic groups-favorable (PI 0-1, n = 73), intermediate (PI 2-3, n = 145), and poor (PI 4-8, n = 88). The median overall survival times for each prognostic group were 16.5, 12.3, and 6.2 months, respectively (P < 0.001). Bootstrapping verified the good fitness of this model for predicting 1-year survival, and the c-index was 0.658. This simple prognostic model could help clinicians to estimate survival in patients with APC who receive palliative chemotherapy.