Stereotactic body radiotherapy in the treatment of adrenal metastases

OBJECTIVES:: To evaluate the dosimetry, clinical outcomes, and toxicity of patients treated with stereotactic body radiotherapy (SBRT) for adrenal metastases. MATERIALS AND METHODS:: From February 2009 to February 2011, a total of 13 patients were treated with SBRT for metastases to the adrenal glands. Median age was 71 years (range, 60.8 to 83.2). Primary sites included lung (n=6), kidney (n=2), skin (n=2), bladder (n=1), colon (n=1), and liver (n=1). Nine patients had metastases to the left adrenal gland and 4 to the right. The median prescribed total dose was 45 Gy (range, 33.75 to 60 Gy), all in 5 fractions. RESULTS:: Median follow-up for living patients was 12.3 months (range, 3.1 to 18 mo). Twelve of the 13 patients (92.3%) were evaluable for local control (LC). The crude LC rate was 100%, with no cases of local or marginal failure. Two patients had a complete response to treatment, 9 patients had a partial response, and 1 patient displayed stable disease. One-year overall survival and distant control were 62.9% and 55%, respectively. Median OS was 7.2 months (range, 2 to 18 mo). Grade 2 nausea was noted in 2 patients. CONCLUSIONS:: SBRT seems to be a safe and effective measure to achieve LC for adrenal metastases.