Stereotactic body radiation therapy for metastases to the kidney in patients with non-small cell lung cancer: a new treatment paradigm for durable palliation.

BACKGROUND: Cancer metastasis to the kidney is a rare event; treatment must take into account the associated and unique anatomic and physiological challenges of treating the kidney. Stereotactic body radiation therapy (SBRT) is a widely emerging modality of radiotherapy touted for its ability to minimize irradiation to surrounding tissues and to provide a vastly shortened treatment course that is highly biologically potent. However, the use of SBRT to treat kidney neoplasms has been described in only a few case reports generally for primary renal malignancies. The role of SBRT in patients with renal metastasis, in providing durable local control and palliation of symptoms, is currently undefined.

METHODS: We conducted a retrospective study of patients with non-small cell lung cancer (NSCLC) and symptomatic renal metastases treated with SBRT. All patients meeting these criteria from a single institution were included.

RESULTS: Symptomatic relief and early tumor control was achieved in all patients. We demonstrate that SBRT is a safe and effective treatment for renal metastases, with ability to spare surrounding tissues and to be delivered in a convenient treatment course of no more than 5 fractions, which lends support to its use in palliative care and appropriate oligometastatic scenarios.

CONCLUSIONS: Further corroborative work is needed to assess kidney function after SBRT and to better characterize the expected duration of local control and palliative relief following SBRT.