EP-1250: Prognostic impact of post-surgery and postadjuvant therapy in resected pancreatic adenocarcinoma

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Table 1. The median follow-up time was 26.87 months. Regional lymph node recurrence alone was only noted in one patient who didn’t undergo RT. Distant metastases (DM) were noted in 17 patients (with RT: 8; without RT: 9). Out of those nine patients who developed DM and didn’t undergo RT, five had been given chemotherapy. Age is significantly related to worse OS (Pearson correlation coefficient=-0.248, p=.037) but not to DFS (-0.191, p=0.111). Positive LNs number is significantly related to both worse OS (-0.244, p=0.041) and DFS (-0.261, p=0.028). Adjuvant RT didn’t significantly improve OS (median: 34.3 vs. 19.7 months, p=0.123) and DFS (median: 30 vs. 17.7 months, p=0.86) (Fig. 1). The patients received adjuvant chemotherapy were with significantly longer OS (median: 31.9 vs. 14.7 months, p=0.007) but not DFS (median: 28.6 vs. 14 months, p=0.42). Conclusion Although the patients who underwent adjuvant CRT were significantly younger, they were also with more advanced diseases. Most of the recurrent events were distant metastases in our study, indicating that D2 dissection might have largely decreased the locoregional failure rate. Adjuvant RT didn’t show significant benefit prolonging OS or DFS. On the other hand, the patients received adjuvant chemotherapy were observed to have significantly longer OS but not DFS. It is possible that the prolonged OS is correlated to the age of patients, rather than a result of chemotherapy. Further randomized controlled trials are required to draw a concrete conclusion. EP-1249 Changes in normal liver volume after high dose radiation in cancer of the liver K. Rajamanickam1, S. Chopra1, R. Engineer1, V. Ostwal1, P. Patil2, S. Mehta2, E. Dhandpani3, K. Joshi3, S.K. Shrivastava1 1 Tata Memorial Hospital, Radiation Oncology, Mumbai, India 2 Tata Memorial Hospital, Digestive Diseases and Clinical Nutrition, Mumbai, India 3 Tata Memorial Hospital, Medical Physics, Mumbai, India Purpose or Objective To report liver volume changes and its impact on liver function following hepatic radiation in patients with primary or secondary hepatic malignancies. Material and Methods From Jan 2015 - April 2016, consecutive patients with unresectable hepatic lesions (hepatocellular cancer (HCC), Cholangiocarcinoma (CCA) or liver metastasis (LM)) who received either high dose radiation (HDRT) or stereotactic radiation (SBRT) and without disease progression were included. All patients were required to have Child Pugh status A-B6 prior to radiation. Total liver volume, gross tumour volume (GTV), normal liver volume (total liver volume- GTV) was determined. Follow up scans were used to determine changes, if any, in normal liver volume. As the dose prescription of each patient was individualised, biologically equivalent dose (BED) were 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, 1st, 2nd and 3rd 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 postadjuvant therapy in resected pancreatic adenocarcinoma G.C. Mattiucci1, A. Arcelli2,3, F. Bertini2, F.A. Calvo4, M. Falconi5, G.P. Frezza3, A. Guido2, J.M. Herman6, R.C. Miller7, V. Picardi8, G. Macchia8, W.F. Regine9, N. Sharma9, M. Reni10, A. Farioli11, A.G. Morganti2, V. Valentini1 1 Policlinico Universitario "A. Gemelli"- Università Cattolica del Sacro Cuore, Department of Radiotherapy, Rome, Italy 2 University of Bologna, Radiation Oncology CenterDepartment of Experimental Diagnostic and Speciality Medicine - DIMES, Bologna, Italy 3 Ospedale Bellaria, Radiotherapy Department, Bologna, Italy 4 Hospital General Universitario Gregorio MaranonComplutense 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 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

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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).

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. Li1, X. Li1, Y. Zhang1, J. Geng1, Y. Cai1, Z. Li2, K. Hu3, J. Yu4, J. Jin5, D. Zhao6, B. Qu7, L. Chen8, J. JI2 1 Key laboratory of Carcinogenesis and Translational Research Ministry of Educati Peking University Cancer Hospital & Institute, Department of Radiation Oncology, Beijing, China 2 Key laboratory of Carcinogenesis and Translational Research Ministry of Educati Peking University Cancer Hospital & Institute, Gastrointestinal Cancer Center, Beijing, China 3 Peking Union Medical College Hospital-Chinese Academy of Medical Sciences and Peking Union Medical College, Department of Radiation Oncology, Beijing, China 4 Peking Union Medical College Hospital-Chinese Academy

of Medical Sciences and Peking Union Medical College, Department of General Surgery, Beijing, China 5 Cancer Hospital-Chinese Academy of Medical Sciences, Department of Radiation Oncology, Beijing, China 6 Cancer Hospital-Chinese Academy of Medical Sciences, Department of Pancrea-gastric Surgery, Beijing, China 7 Chinese People's Liberation Army General Hospital, Department of Radiation Oncology, Beijing, China 8 Chinese People's Liberation Army General Hospital, Department of General Surgery, Beijing, China Purpose or Objective To evaluate the safety and efficacy of preoperative chemoradiotherapy and D2 radical resection in patients with locally advanced gastroesophageal junction carcinoma Material and Methods Gastroesophageal junction carcinomapatients withadenocarcinoma, clinical stage T3-4N0 or any TN13M0, Siewert type II and III were enrolled. After exclusion of peritoneal metastasis with laparoscopic exploration, patients were randomly assigned into surgery group and preoperative chemoradiotherapy plus surgery group. The preoperative chemoradiotherapy group received intensity modulated radiation therapy (IMRT) and concurrent chemotherapyS-1 combined with oxaliplatin weekly plan. The prescription dose was GTV 50Gy/CTV 45Gy/25f/35d with concomitant boost. For the concurrent chemotherapy, S-1 was 30mg/m2 bid, five days a week; oxaliplatin was 40mg/m2 per week, with a total of 5 weeks.Laparoscopic exploration was needed 6 weeks after the end of the preoperative chemoradiotherapy. Patients with no peritoneal metastasis underwent D2 radical resection.Postoperative patients received SOX chemotherapy for 6-8 cycles. This trial (PAPER) is a multicenter randomized controlled studyin Beijing, Tianjin and Hebei Province. Primary endpoint is 3-year DFS, the secondary endpointsare safety and effectivity Results From Sep. 2014 to Jul. 2016,40 cases of 4 centers were enrolled. There were 20 patients in surgery group and 15 cases in the preoperative chemoradiotherapy group. The median age was 61 years (range 33-73).28 were male and 7 were female. Clinical staging were as follows: 20 cT3, 15 cT4; 4 cN0, 8 cN1, 19 cN2, 13 cN3. In the preoperative chemoradiotherapy group ,All patients completed radiotherapy. Six patients cannot tolerate concurrent chemotherapy due to toxicity.There was no grade 4 toxicity.The incidence of grade 3 toxicities were 13.3%: neutropenia. The incidence of grade 2 toxicities were 80%, including: thrombocytopenia (26.7%), neutropenia (6.7%) ,esophagitis and nausea(13.3%). All patients underwent radical D2 resection. Pathological complete response occurred in 13.3% (2/15) of patients. The T and N downstaging rate were 86.7% (13/15) and 100% (11/11). respectively. The tumor regression grade (TRG) were1 case of Grade 0, 2cases of Grade 1 and 3 cases of Grade 2, respectively. Surgery-related complications consisted of anastomotic leakage in 2 (13.3%), infection in 1 (6.7%) and hemorrhage in 1 (6.7%) patients. The perioperative mortality was nil. In the surgery group, Surgery-related complications consisted of anastomotic leakage in1 (6.7%), infection in 1 (6.7%) and hemorrhage in 1 (6.7%) patients. The perioperative mortality was nil Postoperative complications had no significant differences between two groupsConclusion Preoperative Chemoradiotherapy for patients with locally advanced gastroesophageal junction adenocarcinoma showed an acceptable toxicity, promising efficacy and safety for D2 resection. Further conclusions need to be verified by the mid-term results after the completion of