THE EFFECT OF PRETREATMENT NEUTROPHIL/LEUCOCYTE RATIO ON SURVIVAL IN PATIENTS WITH LOCALLY ADVANCED ESOPHAGEAL CANCER RECEIVING CHEMORADIOTHERAPY

FERYAL KARACA¹, ÇIĞDEM USUL AFŞAR², NECAT ALMALI³, SENEM KARABULUT⁴, MEHMET KARABULUT⁵, SIDDIK KESKIN⁶, SERKAN AKBULUT⁷

¹Adana Numune Education and Research Hospital, Department of Radiation Oncology - ²Acibadem Bakirkoy Hospital, Department of Medical Oncology- ³Van YüzüncüYil University Medical Faculty, Department of General Surgery - ⁴Bakirkoy Dr Sadi Konuk Education and Research Hospital, Clinic of Medical Oncology - ⁵Bakirkoy Dr. Sadi Konuk Education and Research Hospital, Department of General Surgery - ⁶Van YüzüncüYıl University Medical Faculty, Department of Biostatistics - ⁷Adana Numune Education and Research Hospital, Department of General Surgery

Introduction: Esophageal cancer (EC) is a highly lethal malignancy. The majority of esophageal cancers are squamous cell or adenocarcinomas. Although the incidence of squamous cell carcinoma (SCC) is decreasing in the United States, the incidence of ade- nocarcinoma arising out of Barrett's esophagus is rising dramatically, although less so in the last few years. Treatment in locally advanced EC (LA-EC) must be multidisciplinary. There are only few factors which affects the prognosis. Our aim was to investigate the prognostic and predictive roles of pretreatment neutrophil/leucocyte (neu/leu) ratios in LA-EC patients receiving chemoradiothe- rapy (CRT).

Materials and methods: Sixty patients with non-metastatic EC (youngest 31 years old) who applied to our hospital between 2011 and 2015 were included in this study. Neu/leu ratios were calculated before CRT and after CRT. The Kaplan-Meier method was used for estimating the survival function from lifetime data. In addition, Cox regression model was also used to explore the relation- ship between the survival of a patient and several explanatory variables.

Results: There was statistical significance between neu/leu ratio before CRT and OS (p= 0.047). One unit increase in neu/leu ratio, increases the probability of being alive 2.725 times (1/0.367). There was statistical significance between neu/leu ratio before CRT and progression-free survival (PFS) (p= 0.046). One unit increase in neu/leu ratio, increases the probability of no relapse 3.559 (1/0.281) times. This means that the patients with higher neu/leu ratio before CRT have a lower risk of relapse.

Discussion and conclusion: Multimodal therapeutic strategies combining chemotherapy, radiation therapy and surgery have been shown to be feasible and to have a positive impact on outcomes by decreasing the risk of locoregional recurrence and often by increasing overall survival. The overall survival (OS) and disease-free survival (DFS) of patients is too short in patients with LA-EC. Our study shows that patients with LA-EC who had higher pretreatment neu/leu ratios have better OS and PFS.