Abstract Book

S679

ESTRO 37

Material and Methods A total of 64 patients with brain metastasis who were treated with whole brain radiation (WBRT) to a dose of 30 Gy in 10 fractions between January 2015 and January 2017 were analyzed retrospectively. The host, disease and treatment related factors including age, KPS (Karnofsky Performance Status), presence of extra- cranial metastases, timing of presentation of brain metastasis, symptoms, the site and status of primary disease were studied. Survival was estimated by Kaplan Meier method. Overall survival in the three RTOG Recursive Partitioning Analysis (RPA) classes were compared using log rank test. Data was analysed using SPSS version 19. Results In the study population, 42 (66%) were females and 22 (34%) were males. The median age of patients was 49.5 years. The common symptoms included headache (65.6%), vomiting (50%), nausea (46.9%) and motor deficits (31.3%). Among the 64 patients, 23(35.9%) of them had brain metastasis diagnosed upfront. Among the remaining 41 patients who developed brain metastasis later to treatment of the initial disease, 10 (18.8%) of them had no evidence of disease at the primary site. Thirty seven (57.8%) patients had extra-cranial metastases. Around 22 (34.4%) patients had KPS <70. The median survival of all patients was 5.0 months (95% CI= 3.2-6.7 months). Median survival of patients with lung primary (46.9%) was 4.0 months while those with breast primary (29.7%) was 6.5 months ( P =0.13). The median survival in RTOG RPA Class I, II and III were 8.0 months, 6.0 months and 3.0 months respectively ( P =0.03). Among the various RPA parameters, only KPS showed statistical significance in multivariate analysis, survival with KPS ≥70 and <70 were 6.1 months and 3.0 months respectively ( P <0.02). Patients who had brain metastases as first presentation of malignancy had a median survival of 4 months as compared to 6 months in those who developed brain metastases subsequent to management of primary disease ( P = 0.3). Patients with solitary brain metastases had a median overall survival of 5.3 months when compared to 4.6 months for patients with multiple brain metastases ( P = 0.7).

YES NO

4.0 6.0 5.3 4.6

BRAIN METASTASES AT PRESENTATION

0.30

SINGLE MULTIPLE

NO. OF LESSIONS

0.70

Conclusion RTOG RPA classes are valid in our study population and reliable for prognostically stratifying patients with brain metastases. Also, Karnofsky Performance Status has been found to be an independent prognostic factor hippocampal avoidance whole-brain radiotherapy for multiple brain metastases Y. Kim 1 , S.H. Kim 2 , J.H. Lee 2 , D.G. Kang 2 1 Kyung Hee University Medical Center, Radiation Oncology, Seoul, Korea Republic of 2 St. Vincent’s Hospital- The Catholic University of Korea College of Medicine, Radiation Oncology, Suwon, Korea Republic of Purpose or Objective To analyze the patterns of failure and survival outcome in patients with multiple brain metastases who received whole-brain radiotherapy (WBRT) with hippocampal avoidance (HA) using simultaneous integrated boost (SIB) on metastatic brain tumors. Material and Methods We retrospectively reviewed 37 patients treate d with HA-WBRT for multiple brain metastases. A total of 25 Gy for whole brain and 35-55 Gy for gross tumors were delivered with 10 fractionations. Local tumor and intracranial progression were defined as a recurrence or tumor progression in simultaneous integrated field and any recurrence or tumor progression within whole brain, respectively. Progression in HA zone was defined as the recurrence within the area expanded 5 mm from HA zone. Results Median follow-up duration was 8.2 months (range, 2.9- 48.5). Intracranial progression was observed in 10 patients (27.0%) and the median duration from the start of HA-WBRT to progression was 7.4 months (range, 0.9- 48.5). Local tumor progression and new metastasis outside SIB field occurred in 7 patients (18.4%) and 8 patients (21.6%), respectively. There was no isolated hippocampal metastasis, except only 1 patient (2.7%) with multiple metastases inside and outside HA zone simultaneously. Median survival time and intracranial PFS rate at 1 year were 19.3 months (95% CI, 10.7-28.1) and 69.5%, respectively, and those for OS were 27.6 months (95% CI, 3.8-48.5) and 72.6%, respectively. Conclusion HA-WBRT was associated with low risk of new metastasis in HA region in the patients with multiple brain metastases. These findings would serve as useful guidance on applying HA-WBRT in clinical practice. EP-1225 Treatment outcomes of 382 patients treated with upfront exclusive radiosurgery for brain metastases L. Schiappacasse 1 , R. Jumeau 1 , C. Tuleasca 2 , V. Vallet 3 , J. Biau 1 , H. Bouchaab 4 , N. Mederos 4 , V. Dunet 5 , M. Roux 5 , R. Meuli 5 , M. Levivier 2 , J. Bourhis 1 1 Centre Hospitalier Universitaire Vaudois, Department of Radiation Oncology, Lausanne Vaud, Switzerland 2 Centre Hospitalier Universitaire Vaudois, Department of Neurosurgery, Lausanne Vaud, Switzerland 3 Centre Hospitalier Universitaire Vaudois, Institut of Radiophysics, Lausanne Vaud, Switzerland 4 Centre Hospitalier Universitaire Vaudois, Department of Medical Oncology, Lausanne Vaud, Switzerland 5 Centre Hospitalier Universitaire Vaudois, Department of Radiology, Lausanne Vaud, Switzerland EP-1224 Treatment outcome of

MEDIAN OVERALL SURVIVAL [MONTHS]

P VALUE

PROGNOSTIC FACTORS

SUB GROUP

8.0 6.0 3.0 6.1 3.0 4.0 6.5

CLASS 1 CLASS 2 CLASS 3

0.03

RPA

≥70 <70

<0.02

KPS

LUNG BREAST

PRIMARY

0.13