The systemic inflammation response index: An independent predictive factor for survival outcomes of bladder cancer stronger than other inflammatory markers

Purpose: We aimed to evaluate the prognostic value of the preoperative systemic inflammation response index (SIRI) to predict the outcomes after open radical cystectomy (RC).

Materials and methods: We conducted a retrospective analysis of the institutional cystectomy database and identified 241 consecutive RC patients. Patient demographics and oncologic outcomes were noted. We calculated the SIRI as previously described (NeutrophilxMonocytes/Lymphocytes), based on the blood-tests at the day before surgery and a minimum >30-day later.

Results: Median follow-up time was 20 months (interquartile range 9-52). Two, 3 and 5 years recurrence free (RFS) and overall survival (OS) rates were 60.6%, 57.1%, 48.9%, and 54.7%, 47.0%, 37.2%, respectively. Patients with preoperative SIRI >1.91 had significantly higher recurrence rates (P < 0.001) and lower OS (P < 0.001). For internal validation, we evaluated postoperative SIRI >1.91 (repeatability testing), and again found significantly higher recurrence rates (P < 0.001) and lower OS (P = 0.004). Persistently high SIRI increased the recurrence and death risk 5.79 and 2.87 fold, respectively. SIRI was also a significant independent predictive factor for RFS and OS in the multivariable cox regression analyses (P < 0.05). SIRI improved the discriminative ability of the models 1.5% to 4.2% and this was quite higher than other inflammatory markers (NLR, MLR, PLR, SII) in all models.

Conclusions: Patients with SIRI >1.91 had significantly higher recurrence and lower OS rates. The cut-off value is validated internally. SIRI is an independent predictive factor for RFS and OS. The contribution of SIRI in the cox models is higher than other inflammatory markers.