Systemic Inflammation and Nutritional Index as a prognostic marker in endometrial cancer

The clinical course of endometrial cancer exhibits substantial variability, underscoring the need for additional biomarkers to enhance risk stratification accuracy. This study aimed to evaluate the prognostic utility of a novel composite index, integrating systemic inflammatory and nutritional parameters, herein termed the Systemic Inflammation and Nutritional Index (SINI), in patients diagnosed with endometrial cancer. This retrospective study included 104 patients with histologically confirmed endometrial cancer. Clinical, pathological, and laboratory data were extracted from institutional medical records. SINI was computed using the formula: platelet count × neutrophil count / lymphocyte count × serum albumin. Receiver operating characteristic (ROC) curve analysis was employed to ascertain the optimal cut-off value, thereby stratifying patients into low and high SINI cohorts. Survival outcomes were evaluated using Kaplan-Meier analysis, and prognostic factors were identified via Cox regression analysis. In multivariable Cox regression analysis, treating SINI as a continuous variable, SINI remained significantly associated with overall survival (HR: 1.656; 95% CI: 1.203-2.279; p = 0.002). Exploratory ROC analysis identified a potential cutoff value of 159.3 for patient stratification. In subsequent cutoff-based analyses, patients with SINI >159.3 demonstrated significantly worse overall survival in multivariable analysis (HR: 2.89; 95% CI: 1.30-6.43; p = 0.009). Kaplan-Meier analysis further corroborated these findings, revealing significantly diminished overall survival in the high SINI group compared with the low SINI group (log-rank p = 0.006). The SINI was associated with survival outcomes in endometrial cancer. As a novel composite biomarker derived from routinely available and cost-effective clinical parameters, SINI offers a potentially practical and accessible tool for refined risk stratification in endometrial cancer patients.