Abstract
BACKGROUND: The impact of the stage of cancer on perioperative mortality remains obscure. The purpose of this study was to investigate whether cancer stage influences 30-d mortality for gastric, pancreatic, and colorectal cancers. METHODS: Data were collected from the National Cancer Database for patients undergoing resections for cancers of the stomach, pancreas, colon, or rectum between 2004 and 2015. The main analysis was conducted among patients with cancer stages 1-3. A sensitivity analysis also included cancer stage 4. Descriptive statistics were used to compare the patients' baseline characteristics. Generalized linear mixed models were used to evaluate the relationship between stage and 30-d mortality, controlling for other disease-, patient- and hospital-level factors. Pseudo R2 statistics (%Δ pseudo R(2)) were used to quantify the relative explanatory capacity of the variables to the model for 30-d mortality. All analyses were performed using SAS 9.4. RESULTS: The cohort included 24,468, 28,078, 176,285, and 64,947 patients with stomach, pancreas, colon, and rectal cancers, respectively. After adjusting for other variables, 30-d mortality was different by stage for all cancer types examined. The factor most strongly associated with 30-d mortality was age (%Δ pseudo R(2) range 14%-39%). The prognostic impact of cancer stage (Stages 1, 2, or 3) on 30-d mortality was comparable to that of the Charlson comorbidity index. CONCLUSIONS: Cancer stage contributes to explaining differences observed in short-term mortality for gastrointestinal cancers. Short-term mortality models would benefit by including more granular cancer stage, beyond disseminated status alone.