The impact of inflammatory biomarkers on overall survival of patients with pancreatic cancer treated with chemoradiation
Authors: K. Holub, C. Conill
Journal: Annals of Oncology (2018)

Introduction: Systemic inflammation is a recognised feature of cancer progression and some inflammatory biomarkers such as Neutrophil-to-Lymphocytes Ratio (NLR) emerge as important prognostic factors of survival outcomes and several studies were carried out to explore NLR in pancreatic cancer. Despite the great interest in the role played by neutrophils in antitumour immunity, other subpopulations of leukocytes, such as eosinophils, seem to be overlooked in cancer setting. We evaluated the prognostic value of NLR in patients diagnosed with pancreatic carcinoma and treated with chemoradiation in our institution, and subsequently we proposed new eosinophil-based ratio expressed as Eosinophil-to-Lymphocyte Ratio (ELR), and we analysed its impact on overall survival of the same cohort of patients. Methods: A total of 60 consecutive patients diagnosed with pathologically-confirmed locally advanced pancreatic cancer in stage I-III and treated with chemo-radiotherapy in our institution from September 2010 to November 2017 were retrospectively evaluated. Three patients who did not complete radiotherapy were eliminated, hence the analysis was based on the data of 57 patients. We analysed the relation between overall survival (OS) and systemic inflammatory biomarkers in blood tests at cancer diagnosis. The ELR was calculated as follows: eosinophil count/lymphocyte count. All patients were divided into two groups using the most discriminative cut-off value of 1.9 for NLR and 0.11 for ELR according to the ROC curves. Statistics: Chi2, Kaplan-Meier test (SPSSv.23), p-value 0.1. Results: Median age at diagnosis was 66.0 years (range 43-83), 33 patients were males (57.9%). Cancer stage at diagnosis was IA in 5 patients (8.8%), IB-5 (8.8%), IIA-9 (15.8%), IIB-30 (52.6%), III-8 (13.5%). Main histology was adenocarcinoma 44 patients (77.2%), localised in the head of the pancreas (41 patients, 71.9%). All patients were treated with chemoradiation based on weekly gemcitabine and External Beam Radiotherapy (EBRT) at a dose of 45Gy (range 32 – 45Gy). Twenty six patients underwent surgery. After a median follow-up of 15.6 months (range 3.4 – 122.0, mean 18.9, SD 16.8), 47 patients (82.5%) were dead at the time of data collection. Kaplan-Meier analyses showed that a high NLR (≥ 1.90) correlated significantly with a shorter OS of cancer patients showing a median OS of 14.6 months in group with NLR ≥ 1.90 (IC 95% 10.8 – 18.4) vs. 26.2 months (IC 95% 13.4 – 38.9) in group with NLR < 1.9 (p = 0.033 Log Rank test, Chi2=4.3, p = 0.019 Breslow, Chi2=5.1). However, a high ELR (≥ 0.12) were associated with better OS, showing a median OS of 21.4 months (IC 95% 11.0 – 31.7) vs. 15.6 months (IC 95% 11.5 – 19.7) in a low ELR group (p = 0.067 Log Rank test, Chi2=3.4, p = 0.057 Breslow, Chi2=3.6). Conclusion: Increased value of NLR was related with worse OS but high ELR correlated with better survival outcome in pancreatic cancer treated with chemoradiation. These results could help identifying patients with higher risk of progression, with the additional benefit that both NLR and ELR are inexpensive and easy to get from the pre-treatment analysis. To our best knowledge, this is the first report evaluating the prognostic value of ELR in pancreatic cancer.