ESTRO 2020 Abstract Book

S478 ESTRO 2020

toxicity were headache (n=21; 26.9%), subjective visual impairment (n=16; 20.5%), and fatigue (n=32, 41.0%). Conclusion Radiotherapy of meningioma provides excellent local control especially in WHO°I meningioma. Further follow up and investigations are needed to analyze patients with recurrent WHO°I or any WHO°II and °III meningioma. PO-0894 Survival in patients with NSCLC with brain metastases treated with WBRT F. Sundbye 1 , G. Persson 1 , K. Skougaard 1 1 Herlev Hospital, Oncology, Copenhagen, Denmark Purpose or Objective Up to 30% of patients with NSCLC develop brain metastases (BM). The prognosis for this patient group is poor. In case of five or less BM, guidelines recommend stereotactic radiosurgery, if more WBRT. Multiple studies have shown WBRT to be associated with progressing neurocognitive side effects and to reduce quality of life significantly. For patients with a short life expectancy it is important to consider treatment with supportive care alone. In a non- inferiority study (QUARTZ) 538 patients with metastatic NSCLC were randomized between WBRT and best supportive care. Primary endpoint was quality-adjusted life-years. In the study there was no difference between the two groups and a median survival of approx. 9 weeks. The study group was criticized for including patients in a poor performance status. In this retrospective study we want to examine if the median overall survival of patients treated with WBRT in our institution is at the same level as in the QUARTZ study. Furthermore, we want to examine how many patients receive futile WBRT and characterize the patients in this group. Material and Methods Patients with NSCLC and BM referred to WBRT in 2016 to 2018 at Herlev Hospital are included. Clinical information regarding patient and disease characteristics, treatment and survival are retrieved. Overall survival was estimated using Kaplan-Meier from WBRT start. Variables possibly influencing overall survival are calculated using Cox proportional hazards regression model. Results 97 patients are included in the study. Thirty-two (33%) of the patients presented with BM at diagnosis. Median overall survival was 86 days (95% CI 72-110). Overall survival rates at 6 months and 1 year were 28.9% (95% CI 21.1-39.5) and 18.6 (95% CI 12.2-28.2), respectively. Survival based on type of systemic treatment (immune checkpoint inhibitors, targeted agents, chemotherapy or no treatment) is shown in the figure.

impact on overall survival. Extracranial control, systemic treatment with both immune checkpoint inhibitors (p<0.0001) and targeted agents (p=0.040) as well as local treatment of BM with stereotactic radiosurgery (p=0.015) were significantly associated with better overall survival. On multivariate analysis (see table), high performance status (p<0.0001), extracranial control (p=0.0007), treatment with immune checkpoint inhibitors (p=0.0001) and stereotactic radiosurgery (p=0.014) were significantly correlated with overall survival.

Conclusion Median overall survival after WBRT was less than 3 months. Patients receiving systemic treatment with immune checkpoint inhibitors and local therapy with stereotactic radiosurgery had a significantly improved survival. Treatment with supportive care alone should be considered for patients with a poor performance status. PO-0895 GPA in brain metastases treated with Stereotactic Radiosurgery M.A. Rodriguez Medizabal 1 , M. Rico Oses 1 , S. Flamarique Andueza 1 , M. Campo Vargas 1 , A. Martin Martinez 1 , L.O. Rosas 1 , E. Martinez Lopez 1 , M. Barrado 1 , S. Pellejero 2 , F. Mañeru 2 1 Complejo hospitalario de Navarra, Radiation Oncology, Pamplona, Spain ; 2 Complejo hospitalario de Navarra, Radiophysics, Pamplona, Spain Purpose or Objective The Graded Prognostic Assessment (GPA), is a prognostic index widely used for patients with brain metastases that has evolved since the initial reports. We wonder if it would be useful to estimate the survival after Stereotactic Radiosurgery (SRS). Our Hypothesis was that the overall survival (OS) of our patients correlates with the GPA.And our main objective to estimate the prognostic as OS of patients with brain metastases treated with RS in our center (CHN) and We retrospectively reviewed patients treated with SRS for brain metastasis between January 2011 and December 2018. We used a multivariate analysis to find association between possible risk factors ( age, size, dose, previous whole brain radiotherapy (WBRT) and previous surgery) and OS. We use intraclass correlation coefficient (ICC), Bland- altman method and survival-agreement plots to measure the agreement between GPA and OS. compare it with GPA. Material and Methods

A performance status of 2 or higher (p<0.0001) and shorter WBRT fractionation schedule (p<0.0001) had a negative