ESTRO 38 Abstract book

S775 ESTRO 38

between November 2011 and April 2018 were enrolled. Radiation treatment was delivered after surgery with or without neoadjuvant chemotherapy with doses ranging between 45 and 56Gy, concurrently with radiosensitizing chemotherapy. Clinical and pathological characteristics of all patients are reported in Table 1. Prognostic impact of surgical margin status were estimated by the Kaplan-Meier method. Log-rank test was used to compare survival between groups.

Conclusion Although a positive surgical margin status may be suggestive of high local recurrence rate, in our small series of patients affected by locally advanced pancreatic cancer treated with adjuvant chemo-radiotherapy there were no DFS or OS difference between PSM and NSM groups. EP-1427 Prognostic role of neutrophil-to-lymphocytes ratio in pancreatic cancer M. Caroprese 1 , I.R. Scognamiglio 1 , M. Tirozzi 1 , F. Piccolo 1 , E. Scipilliti 1 , A. Roscigno 1 , J. De Robbio 1 , M.V. Agbaje Olufemi 1 , M. Sorrentino 1 , A. Farella 1 , C. Oliviero 1 , M. Conson 1 , R. Pacelli 1 1 University “Federico II” School of Medicine, Department of Advanced Biomedical Sciences, Napoli, Italy Purpose or Objective Pancreatic cancer is one of the most aggressive malignancy with dismal 1‐ and 5‐year survival rates of 21% and 3% respectively. Although a high neutrophil-to- lymphocyte ratio (NLR) has been reported to be a predictor of poor survival in patients with pancreatic cancers, its prognostic role in patients with locally advanced pancreatic cancer undergoing radiotherapy remains unclear. The aim of the present study was to determine the prognostic role of NLR in patients with locally advanced pancreatic cancer undergoing radiotherapy. Material and Methods Fifty-three consecutive patients treated by radiotherapy for M0 pancreatic adenocarcinoma at the Radiotherapy Department of the University “Federico II” (Naples, Italia) between January 2011 and April 2018 were enrolled. Radiation treatment was delivered with a dose range between 45 and 56Gy, after a neoadjuvant chemotherapy or after neoadjuvant chemotherapy and surgery, concurrently with radiosensitizing chemotherapy. Two different contexts were defined with regard to target extension, namely tumor site only (T) irradiation, tumor site + prophylactic regional nodes irradiation (T+N). Univariate and multivariate analyses were performed to identify clinicopathological predictors of disease free survival and overall survival, including pre-radiotherapy NLR. NLR was defined as the absolute neutrophil count divided by absolute lymphocyte count. A low-NLR was defined as NLR<1.2 and a high-NLR was defined as NLR≥ 1.20. Results Clinical and pathological characteristics of all patients are reported in Table 1. Median follow-up was 18 months. 47

Results Of 32 total patients, 11 (34.4%) had positive surgical margin (PSM) status and 21 (65.6%) negative surgical margin (NSM) status. The median follow-up period was 28.5 (IQR: 17.25–35.75) months; of the 20 (62.5%) observed deaths, all of these were directly tumor-related. Only six patients (18.8%) resulted free of recurrent disease. First recurrence was loco-regional for 9 patients (29.0%) and distant for 10 (32.3%) patients; 7 patients (22.6%) presented both. Median DFS among the PSM and NSM groups was 11 versus 13 months, respectively ( P =.965); no differences in OS were also seen between the two groups ( P =.550). The results are reported in Figure 1.