ESTRO 36 Abstract Book

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S612 ESTRO 36 2017
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2 UF Health Cancer Center-Orlando Health, Radiation
Oncology, Orlando, USA
Purpose or Objective
We examined the impact of patient and tumor-specific
factors on overall survival in patients with brain
metastases from non-small cell lung cancer (NSCLC)
treated with stereotactic radiosurgery (SRS).
Material and Methods
We undertook an institutional review board-approved
retrospective analysis of patients treated with LINAC-
based SRS for brain metastases from non-small cell lung
cancer between November 2008 and July 2016 at our
institution. We identified 418 metastatic brain lesions
treated in 136 non-small cell lung cancer (NSCLC)
patients. Out of the 418 treated brain metastases, 376 had
at least one follow up study. Patients were followed with
serial brain MRIs with contrast to assess for local
progression and recurrence every 2-3 months. Patient
characteristics collected included: extracranial disease
(ECD) status, Karnofsky performance status (KPS), tumor
histology, history of whole brain radiation therapy, history
of IMRT, history of craniotomy, date of death or last
clinical contact, and age at initial SRS
treatment. Treatment characteristics were obtained from
the treatment plans, including tumor volume, prescription
dose, prescription isodose, and maximum dose. Actuarial
patient survival was defined as the time in months from
initial SRS treatment to date of death or date of last
clinical contact. The overall survival was calculated from
date of first SRS treatment session to date of death or
progression via the Kaplan-Meier method. At the time of
initial treatment, 14% of patients were categorized as RPA
class I, 71% as RPA class II, and 15% as RPA class III. Five
patients were ALK positive,43 were ALK-negative.
Nineteen patients were EGFR positive and 44 were EGFR
negative.
Results
The median overall survival was 13.2 months. The Kaplan-
Meier overall survival estimates at 6 and 12 months were
81.4% and 52.8%, respectively. There was a significant
difference in survival between adenocarcinoma vs.
squamous histology, 14.3 months vs. 8.1 months (p-value
= 0.013). Patient pre-treatment RPA class was predictive
of survival (p-value = 0.047). The median survival was 39.8
months for RPA class I, 12.8 months for RPA class II, and
7.5 months for RPA class III. The median survival for
inactive ECD was 15.3 months and 11.5 months for inactive
ECD (p-value= 0.034). Concurrent or prior WBRT, age, ALK
mutation status, EGFR status, and KPS did not have a
significant impact on survival following SRS.
Conclusion
SRS is an important modality in the management of
discrete brain metastatic disease. Survival following SRS
for NSCLC brain metastases varies widely, and the
prognosis may depend on a broad range of tumor and
patient parameters. Among our patient group, those with
adenocarcinoma versus squamous histology, inactive
extracranial disease status, and favorable RPA class had
the longest overall survival. Prior or concurrent WBRT,
age, ALK mutation status, EGFR status, and KPS were not
predictive of survival.
EP-1132 Hypofractionated Stereotactic Reirradiation
for Recurrent High-grade Glioma
L. Hynkova1, P. Slampa1 , T. Kazda1, J. Garcic1, M. Vrzal1,
P. Fadrus2, R. Belanova3, I. Sikova4, D. Dvorak 1, H.
Dolezelova1, P. Pospisil1
1 Masaryk Memorial Cancer Institute, Clinic of Radiation
Oncology, Brno, Czech Republic
2 The University Hospital Brno, Department of
Neurosurgery, Brno, Czech Republic
3 Masaryk Memorial Cancer Institute, Department of
Radiology, Brno, Czech Republic
4Masaryk Memorial Cancer Institute, Department of
Neurology, Brno, Czech Republic
Purpose or Objective
The treatment for recurrent high-grade glioma is
diversified. In this retrospective analysis, we evaluated
outcomes of stereotactic hypofractionated radiotherapy
(SRT) in patients re-treated for reccurent high-grade
glioma.
Material and Methods
From July 2004 to April 2013, 27 patients were
treated. At the initial diagnosis, all patients underwent
open-surgery resections to remove maximum of their
tumors. SRT was performed with multileaf
microcollimator systems (BrainLab) for linear accelerator.
The dose given ranged from 16–25 Gy in a median
five fractions (range, 1–5 fractions). The median volume
of the tumor was 5,1 cm3 (range, 0,03–33,7 cm3). All the
patients were treated with radiotherapy previously (range
dose 50–60 Gy). Only patients with Karnofsky performance
Status (KPS) > 60 were re-irradiated. The median age was
46 years (21–58). 9 patients (33 % ) had a glioblastoma
diagnosis and 18 patients (67 %) were affected by grade III
glioma (anaplastic astrocytoma/anaplastic
oligoastrocytoma). After reirradiation 18 patients (67 %)
received chemotherapy and 8 patients (30 %) received
study of dendritic cells.
Results
The median overall survival from the date of salvage
stereotactic radiotherapy was 13,9 months (95% CI 7,7–
20,5 months) with the range of follow-up from 2,9 to 128,9
months and the median overall survival following initial
treatment was 46,8 months (95% CI 32–121,4). The survival
was significantly shorter in the subgroup of patients with
grade IV gliomas (p < 0,0036, HR 7,45, 95% CI: 1,62–34,31).
From the date of stereotactic radiotherapy, the 1-year, 3-
year and 5-year overall survival was 50,2 % (95% CI 33,7–
77,4%), 20,9 % (95% CI 9,6–45,6 %) and 12,5 % (95% CI 4,4–
36,1 %), respectively. The patients who underwent
resection of subsequent post-stereotactic radiotherapy
recurrence had better survival (p < 0,0142, HR 4,377, 95%
CI:1,23-15,55). The increased survival was also observed
in patients with longer intervals between initial treatment
and stereotactic reirradiation (p < 0,0205, HR 0,984 95%
CI: 0,07–1,0). The radiological response to reirradiation
evaluated by MRI has not been a predictor of survival. No
severe toxicity was recorded (any case of radionecrosis).
Conclusion
In our experience, hypofractionated stereotactic radiation
therapy could be a safe and feasible option for recurrent
high grade glioma.
EP-1133 Multifraction Radiosurgery for Large Brain
Metastasis: Initial Results from Brazilian Experience.
A. Borges1, L. Ercolin1, M. De Mattos1, J. Alexandre1, M.
Giglioli1, A. Camargo1, D. Marconi1, D. Fonseca1, T.
Kaprealian2
1Barretos Cancer Hospital, Radiation Oncology, Barretos,
Brazil
2UCLA, Radiation Oncology, Los Angeles, USA
Purpose or Objective
To evaluate the clinical outcomes with linear accelerator-
based multifraction stereotactic radiosurgery (mSRS), 3
fractions, to treatment of the large Brain Metastasis in
Brazilian Population.
Material and Methods
Patients with brain metastases were included with 30 days
or more of the end of the mSRS, between May 2015 to
August 2016.
The primary endpoint was acute toxicity and the
secondary endpoints were overall survival, local control
(in field) and Regional recurrence free survival. Prognostic
factors were analyzed, as Ds-GPA, RPA, the number of
treated lesions, the major lesion, time between the last