3277 - A Systemic Inflammation Response Index (SIRI) correlates with survival and could be a Predictive Factor for mFOLFIRINOX in Metastatic Pancreatic Cancer (PC)

Background

Cancer-related inflammation is a distinctive feature of the development and progression of PC. However, the relationship between the systemic inflammatory response and survival has not been evaluated as a predictive factor of chemotherapy. The aim of this study was to evaluate the prognostic and predictive value of a baseline SIRI based on peripheral neutrophil, monocyte, and lymphocyte counts in metastatic PC.

Methods

Retrospective review of 178 metastatic pancreatic cancer patients. Associations between overall survival (OS), time to progression (TTP), chemotherapy schedule and SIRI at diagnosis were analyzed.

Results

Median age 67 years, 52% were male. First line chemotherapy regimens: 41% Gemcitabine, 31% Gemcitabine plus Nab-Paclitaxel and 17% mFOLFIRINOX. Patients with SIRI<2.3x10⁹ showed a statistically significant improvement in OS compared to SIRI≥2.3x10⁹ [16 months versus 4.8 months, Hazard Ratio (HR) 2.87, Confidence Interval (CI) 95% 2.02-4.07, p < 0.0001] that was confirmed in multivariate analysis. In addition, patients with SIRI<2.3x10⁹ showed a longer TTP (12 versus 6 months, HR 1.92, IC 95% 1.314-2.800, P = 0.001). Furthermore, we observed that patients with SIRI ≥2.3x10⁹ are more likely to benefit from mFOLFIRINOX therapy. Patients with an elevated SIRI treated with mFOLFIRINOX versus Gemcitabine plus Nab-Paclitaxel and Gemcitabine showed a clinically and statistically significant difference in median OS of 17 months compared to 6 and 4 months respectively (p < 0.001). Conversely, the difference was not clinically significant in the SIRI<2.3x10⁹ subgroup: 15.9 months versus 16.5 and 16, respectively.

Conclusions

An elevated SIRI (≥2.3x10⁹) is an independent prognostic factor for survival in patients with metastatic pancreatic cancer. Patients with an elevated SIRI (≥2.3x10⁹) show an increased benefit from mFOLFIRINOX in comparison to other first line chemotherapy regimens. These results raise the issue of appropriately selecting patients who would benefit of a more intensive first-line chemotherapy regimen.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.