Stereotactic Body Radiotherapy for Adrenal Gland Metastases: Single-Center Experience
Gökhan YAPRAK1,Naciye IŞIK1,Cengiz GEMİCİ1,Harun DEMİR1,Melike PEKYÜREK1
1Departmet of Radiation Oncology, University of Health Sciences Dr. Lütfi Kırdar Kartal Training and Research Hospital, Istanbul-Turkey DOI : 10.5505/tjo.2019.2104 OBJECTIVE
In this study, we aimed to analyze the results of stereotactic body radiotherapy (SBRT) in patients with adrenal gland metastasis due to different primary tumors.

26 patients with 29 adrenal gland metastases who were treated between 2011-2018 with Cyberknife Robotic System were evaluated retrospectively.

The origin of adrenal gland metastasis was lung in 22 patients, breast in 1 patient, parotid gland in 1 patient, and sarcoma in 2 patients. Fifteen patients (58 %) had other organ metastasis in addition to the adrenal metastases. Six patients were treated for synchronous metastasis and 20 patients for metachronous metastasis. SBRT was performed in median 3 fractions (3?5 fractions), and the median prescription dose to PTV was 30 Gy (18- 45 Gy), with a BED10 (Biological Equivalent Dose) value of 60 Gy (28.8-112,5 Gy). The median follow-up time was 11 months (1-34 months), and median overall survival was 12 months after SBRT, 1,2-years survival rates were 49,7%, 21% respectively. Median time to local failure was not reached, and the 6-months, 1 and 2-years local failure free survival rates were 78,6%, 66,5% and 66,5% respectively. The presence of metastatic disease outside the adrenal gland was found to be a significant prognostic factor on survival after SBRT in both univariate and multivariate analyzes, (HR:3; 95% CI 1,06-8,55 p:0,04). In general treatment was well tolerated and no major acute toxicities were observed.

SBRT provides high local control rates and a well tolerated treatment in patients with adrenal gland metastases. Survival is particularly encouraging for patients with solitary adrenal metastasis. Keywords : Adrenal metastasis; cyberknife; stereotactic body radiotherapy