ESTRO 37 Abstract book

ESTRO 37

S396

12 Keimyung University School of Medicine, Radiation Oncology, Daegu, Korea Republic of 13 Uijeongbu St. Mary’s Hospital- The Catholic University of Korea, Radiation Oncology, Uijeongbu, Korea Republic of Purpose or Objective To evaluate the efficacy and toxicity in patients with Child-Pugh B (CP-B) hepatocellular carcinoma (HCC) treated with radiotherapy (RT). Material and Methods We retrospectively reviewed 184 HCC patients with CP-B were treated with RT between 2009 and 2014 at 13 institutions in Korea. The majority (88%) received 3- dimensional conformal RT; intensity modulated RT was applied in 12%. The total dose ranged from 31.5 Gy to 64 Gy (median 44 Gy) with the fraction size of 1.5 Gy to 5 Gy. The biologically effective dose (BED) (α/β=10 Gy) was 40.4 to 89.6 Gy 10 (median 56 Gy 10 ). To examine the incidence of hepatic toxicity, we defined a decline in CP score by ≥2 points and the occurrence of the classic radiation induced liver disease (RILD) or nonclassic RILD within 3 months after RT as significant adverse events. Local progression free survival (LPFS), intrahepatic progression free survival (IHPFS), and overall survival (OS) rated were calculated from RT start dates using the Kaplan-Meier method. Log-rank analysis was used for group comparisons. Multivariate analysis were performed using Cox proportional hazard models. Results Patients were 39 to 85 years of age (median 58 years), and 86% were male. Eastern Cooperative Oncology Group performance scores were 0 in 54 patients, 1 in 80, 3 in 47, and 3 in 3. The most common underlying liver disease was hepatitis B (73%), followed by hepatitis C (14%), and alcoholic hepatitis (7%). Initial CP score was 7 in 114 patients, 8 in 57 patients, and 9 in 13 patients. According to mUICC stage, T1, T2, T3, and T4 was 10, 21, 61, and 92 patients. Twenty six patients had nodal involvement. The HCC size was 1 to 21 cm (median 5 cm). The number of HCCs ranged from 1 to 10. Portal vein tumor thrombosis (PVTT) was presented in 122 patients. The median OS was 9 months. The 1-year OS, LPFS, and IFPFS rates were 35%, 57%, and 18%, respectively. Within 3 months after RT, a decline in CP score by ≥2 points occurred in 59 patients (31%). Twenty-one patients (12%) experienced classic RILD and 17 patients (9%) experienced non-classic RILD. On univariate analysis, hepatitis, HCC size >5cm, advanced T stage, nodal involvement, numbers of HCC ≥4, the presence of PVTT, pre_RT AFP >200 ug/L , AFP reduction ≤50% at 1 month, a decline in CP score by ≥2 points, BED ≤53 Gy 10 , and no adjuvant treatment were associated with poor OS. On multivariate analysis, a decline in CP score by ≥2 points and no adjuvant treatment were negative prognostic factors on OS (both p <0.001). Conclusion Although patients had impaired liver function and most was advanced stage, our study demonstrated that the application of RT is effective in HCC patients with CP-B. PO-0767 Local tumor control in patients with HCC treated with SBRT or TACE: a propensity score analysis E. Gkika 1 , D. Bettinger 2 , M. Schultheiss 3 , N. Glaser 4 , S. Lange 2 , L. Maruschke 5 , N. Buettner 3 , S. Kirste 1 , U. Nestle 1,6 , A.L. Grosu 1 , R. Thimme 2 , T. Brunner 1 1 Medical Center University of Freiburg- Faculty of Medicine- University of Freiburg, Department of Radiation Oncology, Freiburg, Germany 2 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg-, Department of Medicine II-, Freiburg, Germany 3 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg-, Department of

Medicine II, Freiburg, Germany 4 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg, Department of Medicine II, Freiburg, Germany 5 Medical Center University Freiburg- Faculty of Medicine, Department of Radiology, Freiburg, Germany 6 Kliniken Maria Hilf- Moenchengladbach- Germany, Department of Radiation Oncology, Moenchengladbach, Germany Purpose or Objective Stereotactic body radiation therapy (SBRT) has shown to be effective and safe in patients with hepatocellular carcinoma (HCC). However, there is no consensus in which setting SBRT should be used in patients with HCC. Therefore, the aim of our propensity score matched analysis was to analyze the efficacy of SBRT in comparison to transarterial chemoembolization in intermediate and advanced HCC Material and Methods Patients treated with first TACE between 2003 and 2015 were retrospectively enrolled and analyzed. Further, HCC patients who were allocated to SBRT treatment between 2013 and 2016 were prospectively analyzed by reviewing medical records, laboratory parameters and imaging studies. Propensity score matching was performed to adjust for differences in baseline and tumor characteristics of TACE and SBRT patients. The primary endpoint was the disease control rate (DCR) one year after treatment, overall survival (OS) and 1-year mortality. Results Patients treated with SBRT (n=35) presented with advanced HCC and significantly impaired liver function compared to patients treated with TACE (n=367) in the unmatched cohort. The DCR one year after treatment in the unmatched cohort was 74.4% for patients treated with TACE compared to 84.8% in the SBRT group. However, patients treated with TACE showed significantly improved OS compared to SBRT patients (17.0 months vs. 9.0 months, p=0.016). After propensity score matching, the DCR in the TACE (n=70) and SBRT (n=35) group was comparable (82.9% vs. 84.8%, p=0.805) and OS did not differ significantly in both groups (11.0 months vs. 9.0 months, p=0.492). Conclusion SBRT in selected HCC patients is effective and safe and may show comparable DCR at one year, OS and 1-year mortality compared to patients treated with TACE. PO-0768 Patterns of nodal relapse after D2 dissection in gastric cancer: rethinking the target volume Y. Wang 1 , H. Ran 1 , Z. Menglong 1 , L. Guichao 1 , W. Yan 1 , Z. Zhen 1 1 Fudan University Cancer Hospital, Department of Radiation Oncology, Shanghai, China Purpose or Objective The goal of the study was to map the location of regional nodal recurrence in patients with gastric cancer who performed radical gastrectomy and D2 dissection, and rethink the clinical target volume (CTV) in adjuvant radiotherapy. Material and Methods Between January 2004 and October 2015, 129 patients with gastric cancer following D2 resection and experienced regional recurrence were retrospectively examined according to the criteria of Japanese Classification of Gastric Carcinoma (JCGC). All diagnostic images including CT, MR or PET-CT were reevaluated by two experienced radiation oncologists with gastrointestinal specialty. The lymph nodes were hand- drew proportionally on the template CT images of a standard patient by referencing surrounding anatomic