Markers of Systemic Inflammatory Response are Prognostic Factors in Patients with Pancreatic Neuroendocrine Tumors (PNETs): A Prospective Analysis

The prognosis and behavior of pancreatic neuroendocrine tumors (PNETs) vary and may be divergent even at the same stage or tumor grade. Markers of systemic inflammatory response are readily available and are inexpensive, and have been shown to be prognostic factors in several cancers. The aim of this study was to evaluate the prognostic utility of markers of systemic inflammatory response in patients with PNETs. A prospective study of 97 patients with PNETs was performed (median follow-up of 15 months, range 12-73 months). Neutrophil-to-lymphocyte ratios (NLRs) and lymphocyte-to-monocyte ratios (LMRs) were calculated at baseline and preoperatively. The primary outcome measures were progression-free survival (PFS) and recurrence-free survival (RFS) after curative resection. Among all patients, an NLR > 2.3 [hazard ratio (HR) 2.53, 95% confidence interval (CI) 1.05-6.08, p = 0.038] and the presence of distant metastases (HR 2.8, 95% CI 1.26-6.21, p = 0.012) were independent predictors of disease progression. Among patients who did not undergo surgery during the study period, both platelet-to-lymphocyte ratio (PLR) > 160.9 (HR 5.86, 95% CI 1.27-27.08, p = 0.023) and mean platelet volume > 10.75 fL (HR 6.63, 95% CI 1.6-27.48, p = 0.009) were independently associated with worse PFS on multivariable analysis. Among patients who underwent complete resection, an LMR < 3.46 was associated with a worse RFS (HR 9.72, 95% CI 1.19-79.42, p = 0.034). PLR > 160.9 and an MPV > 10.75 fL at baseline are independent predictors of disease progression, while an LMR < 3.46 is an independent predictor of tumor recurrence after complete resection in patients with PNETs.