162P - Hypofractionated radiotherapy for pulmonary metastases from hepatocellular carcinoma: Treatment response and prognostic factors affecting survival

Abstract

BackgroundTo evaluate clinical usefulness of hypofractionated radiotherapy (HRT) for pulmonary metastases from hepatocellular carcinoma (HCC) and investigate the prognostic factors affecting treatment outcome. MethodsFrom March 2006 to May 2018, 58 patients with less than five pulmonary metastases from HCC who underwent HRT were analyzed retrospectively. Primary endpoint was treatment response rate. Secondary endpoints were progression-free survival, overall survival, prognostic factors affecting treatment outcomes and treatment-related side effects. ResultsThe treatment response (complete and partial response) rate was 77.6 %, and the maximum treatment response was presented between 1 to 3 months after completion of HRT. The local control rate was 63.8 %. The median survival time was 16.3 months for all patients. The 1-year and 3-year overall survival rates were 79.3 % and 37.9 %, respectively. The median progression-free survival time was about 5 months and eighty-six percent of the patients (n = 50) showed post-treatment disease progression. Multivariate analysis identified the common prognostic factors for both OS and PFS as the planning target volume and maximal treatment response after HRT. The progression-free survival period was also a prognostic factor for OS in multivariate analysis. The grade 3 and 4 severe toxicities were reported in 4 and 3 patients, respectively. ConclusionsThe considerable treatment outcome and acceptable toxicity may indicate clinical usefulness of HRT for patients who have less than five pulmonary metastases from HCC.Table162P Prognostic factorsTableOSPFSMedian±SD*p value†Median±SD*p value†Variable(mo)UVAMVA(mo)UVAMVAAge0.6500.0300.012< 6016.2±4.63.7±3.7≥ 6021.4±7.94.9±1.3ECOG0.0970.401044.3±17.28.0±3.01, 216.3±4.53.7±1.3PTV size0.0170.0030.0270.003< 19 cc30.3±8.55.7±2.0≥ 19 cc11.5±2.13.0±0.3Type I max response0.0130.0000.029CR+PR20.1±4.35.1±1.6SD+PD6.0±1.21.3±1.1Type II max response0.0060.0140.018CR+PR+SD20.1±3.55.1±1.3PD4.6±1.81.2±0.1PFS period0.0010.003< 5 mon10.6±3.5≥ 5 mon44.3±11.7Overall16.3±4.44.9±1.2 Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.