ESTRO 36 Abstract Book

S666 ESTRO 36 2017 _______________________________________________________________________________________________

11 University of Bologna, Department of Medical and Surgical Sciences - DIMEC, Bologna, Italy Purpose or Objective Prognosis of pancreatic adenocarcinoma (PAC) is so dismal that annual mortality and incidence rates overlap. Several studies suggested that preoperative CA19.9 (prCA19.9) could be a useful prognostic marker in patients treated with surgery +/- adjuvant therapies. The purpose of this study was to determine whether post-surgical CA19.9 (poCA19.9) or post-adjuvant CA19.9 (paCA19.9) or a change in prCA19.9 to poCA19.9 could predict pattern of failure in terms of local control (LC) and metastasis-free survival (DMFS). Material and Methods We performed a multicenter retrospective study and we selected for this analysis 67 pts Antigen Lewis positive (prCA19.9 > 5U/ml), judged to be secretors of CA19.9. We used the Kaplan-Meier method and the log-rank test to investigate differences in LC and DMFS between groups defined based on clinical and pathological factors, different poCA 19.9 cutoff (37, 100 U/mL), paCA 19.9 cutoff (37 U/mL), and differences (%) between prCA19.9 and poCA19.9 levels. Results Demographic data and results are shown in Table 1. Median follow-up (FU) was 18 months (2-225). At univariate analysis, levels of poCA19.9 >37 U/ml (p= 0.009) or >100 (p< 0.001) and levels of paCA19.9 >37 U/ml (p= 0.009) were significantly associated with a worse DMFS. A change in prCA19.9 to poCA19.9 did not impact LC and DMFS. CRT did not impact pattern of failure in the whole patients population. Only in patients with poCA19.9 > 37 U/ml CRT significantly affected LC (63.6% for patients treated with CRT vs 40.0% for patients not treated with CRT; p = 0.008).

calculated. Univariate analysis was perform out to determine impact of total dose, GTV at treatment, use of systemic chemotherapy, primary tumour type, baseline liver function status, age and viral marker status on normal liver volume and liver function during follow up. Reduction in liver volume at follow-ups were analysed with paired t-test. p value of <0.05 was considered significant. Results Thirteen patients received either SBRT or HDRT. Out of these 6/7 patients with HCC received TACE prior to RT initiation and all received sorafenib while 3/4 with CCA received gemcitabine and cisplatin concurrently with radiation. Another 2 were treated for LM. The Median BED was 59.5 Gy (48 - 85.5 Gy). The follow up scans were performed at 1 month and 4 monthly thereafter. The median normal liver volume at baseline, 1 st , 2 nd and 3 rd follow up was 1105 (423-2100) cc, 918 (614 - 1899) cc, 778 (490 - 1746) cc and 816 (576 - 2101) cc for the entire cohort and 1098 (423 – 2100) cc, 886 (614 – 1899) cc, 778 (490 - 1746) cc and 750 (576 – 1136) cc for patients with primary hepatic malignancy (PHM). The reduction in liver volume was statistically significant at 4 months (p=0.05) in entire cohort. In PHM cohort, at 4 and 8 months reduction in liver volume were found significant (p=0.05 and p=0.05, respectively). Deterioration of Childs score was presented in 2/13 patients. This loss in liver function could represent ongoing radiation effects on compensatory liver hypertrophy or hepatocyte regeneration. However no correlation was seen between child score deterioration and loss of liver volume. On univariate analysis, the higher normal liver volume at baseline irradiated shows statistically significantly higher loss of liver volume (p=0.005). None of other tumour or treatment related factors had impact on liver volume changes. Conclusion The reduction in liver volume at follow up does not correlate with any tumour or treatment parameters other than normal liver volume at baseline. This ongoing loss of hepatic function and reduced hepatocyte regeneration after hepatic radiation needs further investigation. EP-1250 Prognostic impact of post-surgery and post- adjuvant therapy in resected pancreatic adenocarcinoma G.C. Mattiucci 1 , A. Arcelli 2,3 , F. Bertini 2 , F.A. Calvo 4 , M. Falconi 5 , G.P. Frezza 3 , A. Guido 2 , J.M. Herman 6 , R.C. Miller 7 , V. Picardi 8 , G. Macchia 8 , W.F. Regine 9 , N. Sharma 9 , M. Reni 10 , A. Farioli 11 , A.G. Morganti 2 , V. Valentini 1 1 Policlinico Universitario "A. Gemelli"- Università Cattolica del Sacro Cuore, Department of Radiotherapy, Rome, Italy 2 University of Bologna, Radiation Oncology Center- Department of Experimental Diagnostic and Speciality Medicine - DIMES, Bologna, Italy 3 Ospedale Bellaria, Radiotherapy Department, Bologna, Italy 4 Hospital General Universitario Gregorio Maranon- Complutense University, Department of Oncology, Madrid, Spain 5 Università Politecnica delle Marche, Department of Surgery, Ancona, Italy 6 Johns Hopkins University School of Medicine, Department of Radiation Oncology and Molecular Radiation Sciences, Baltimore, USA 7 Univeristy of Virginia, Department of Radiation Oncology, Charlottesville, USA 8 Fondazione di Ricerca e Cura "Giovanni Paolo II", Radiotherapy Unit, Campobasso, Italy 9 University of Maryland Medical Center, Department of Radiation Oncology, Baltimore, USA 10 S. Raffaele Scientific Institute, Department of Oncology, Milan, Italy

Conclusion Monitoring CA19.9 seems a useful parameter to modulate the management of PAC patients in terms of choice of adjuvant treatment and follow-up intensity. EP-1251 Safety and Efficacy of Preoperative Chemoradiotherapy in Patients with Locally Advanced EGJ Cancer Y. Li 1 , X. Li 1 , Y. Zhang 1 , J. Geng 1 , Y. Cai 1 , Z. Li 2 , K. Hu 3 , J. Yu 4 , J. Jin 5 , D. Zhao 6 , B. Qu 7 , L. Chen 8 , J. JI 2 1 Key laboratory of Carcinogenesis and Translational