ESTRO 2020 Abstract Book

S556 ESTRO 2020

ulcer and 1: stenotic fibrosis). Responses were evaluated in 39 pts (1 lost): 24 pts (61.5%) had PD (7 distant, 8 local, 9 local and distant). Median TTLP and TTDP from end of RT were 18.4 and 13.7 months, respectively. At a median follow up of 36.6 months (7.33- 115.83 m) 20 pts (48%) were alive; 1, 3 and 5 years OS were 95%, 50% and 22.5%, respectively. Conclusion Postoperative intensity-modulated hypofractionated IGRT concomitant to capecitabine in pts with biliary tract carcinoma is feasible with a good toxicity profile and promising outcome. PO-1045 Addition of SBRT following TACE is associated with a survival benefit in Hepatocellular Carcinoma R. Kabarriti 1 , N.P. Brodin 1 , K. English 1 , N. Ohri 1 , A. Kaubisch 1 , M. Kinkhabwala 1 , S. Kalnicki 1 , C. Guha 1 , M.K. Garg 1 1 Montefiore Medical Center- Albert Einstein College, Radiation Oncology, New York, USA Purpose or Objective Most recent Barcelona Clinic Liver Cancer (BCLC) staging system recommends trans-arterial chemoembolization (TACE) or systemic therapy for patients with BCLC intermediate (stage B) or advanced (stage C) stage Hepatocellular Carcinoma. Whether the addition of Stereotactic Body Radiation therapy (SBRT) to TACE can improve outcomes including overall survival is not fully elucidated. In this study, we evaluate the impact of SBRT given after TACE on freedom from local progression (FFLP) Patients with non-metastatic, unresectable HCC receiving TACE as initial therapy between 2010-2018 at an urban medical center were identified. Kaplan-Meier survival analysis, multivariable Cox regression and landmark analysis were used to examine the association between FFLP and OS with TACE vs. TACE+SBRT. Results Of 216 patients identified, 167 (77.3%) received TACE only and 49 (22.7%) received TACE+SBRT. With a median follow- up of 14 months, 219/377 lesions progressed (58.1%), 204 in the group with TACE alone and 15 in the group with TACE+SBRT (p<0.001). Three-year FFLP was 22.1% for TACE alone vs. 66.3% for TACE+SBRT (p<0.001), and Table 1 shows addition of SBRT was associated with significantly better FFLP on multivariable analysis. Figure 1 illustrates the actuarial FFLP and OS benefit with the addition of SBRT as compared to TACE alone. The 3-year OS was 65.2% for patients with lesions treated with TACE alone vs. 93.0% for patients where any lesion received TACE+SBRT as the first ablative therapy (p<0.001), and this benefit was robust against immortal time bias on 6-month landmark analysis. On multivariable analysis, the addition of SBRT was a borderline independent predictor of OS for all patients (HR=0.50, 95%CI: 0.24-1.04, p=0.065) and a significant predictor for patients with BCLC stage B or C disease (HR=0.19, 95%CI: 0.04-0.87, p=0.032). and Overall survival. Material and Methods

Conclusion Adding SBRT following TACE improved FFLP and OS among patients with hepatocellular carcinoma, especially in those with BCLC stage B or C disease.