A preoperative nomogram to predict the risk of perioperative mortality following gastric resections for malignancy.

Introduction: Surgery remains one of the major treatment options available to patients with gastric cancer. The aim of this study was to develop a preoperative nomogram based on the presence of comorbidities to predict the risk of perioperative mortality following gastric resections for malignancy.

Methods: The Nationwide Inpatient Sample (NIS) database was used to create a nomogram using SAS software. The training set (years 1993, 1996-97, 1999-2000, 2002, 2004-05) was used to develop the model which was further validated using the validation set (years 1994-95, 1998, 2001, and 2003).

Results: A total of 14,235 and 9,404 patients were included in the training and validation sets, respectively, with overall actual observed perioperative mortality rates of 5.9 % and 6.6 %, respectively. The decile-based calibration plots for the training and validation sets revealed a good agreement between the observed and nomogram-predicted probabilities. The accuracy of the nomogram was further reinforced by a concordance index of 0.75 (95 % confidence interval 0.73 to 0.77) which was calculated using the validation set.

Conclusion: This preoperative nomogram may accurately predict the risk of perioperative mortality following gastric resections for malignancy and may be used as an adjunctive clinical tool in the preoperative counseling of these patients.