Safety and Efficacy of Stereotactic Ablative Radiation Therapy for Renal Cell Carcinoma Extracranial Metastases

Journal Article · Mon May 01 00:00:00 EDT 2017 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2017.01.032· OSTI ID:22649911

Wang, Chiachien Jake ^[1]; Christie, Alana ^[1]; Lin, Mu-Han; Jung, Matthew; Weix, Derek; Huelsmann, Lorel; Kuhn, Kristin; Meyer, Jeffrey; Desai, Neil; Kim, D. W. Nathan ^[2]; Pedrosa, Ivan ^[3]; Margulis, Vitaly; Cadeddu, Jeffrey; Sagalowsky, Arthur; Gahan, Jeffrey ^[4]; Laine, Aaron ^[2]; Xie, Xian-Jin ^[1]; Choy, Hak ^[2]; Brugarolas, James ^[1]; Timmerman, Robert ^[2] ; others, and

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1. Kidney Cancer Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas (United States)
2. Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)
3. Department of Radiology, Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas (United States)
4. Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)

Purpose: Renal cell carcinoma is refractory to conventional radiation therapy but responds to higher doses per fraction. However, the dosimetric data and clinical factors affecting local control (LC) are largely unknown. We aimed to evaluate the safety and efficacy of stereotactic ablative radiation therapy (SAbR) for extracranial renal cell carcinoma metastases. Methods and Materials: We reviewed 175 metastatic lesions from 84 patients treated with SAbR between 2005 and 2015. LC and toxicity after SAbR were assessed with Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Predictors of local failure were analyzed with χ{sup 2}, Kaplan-Meier, and log-rank tests. Results: In most cases (74%), SAbR was delivered with total doses of 40 to 60 Gy, 30 to 54 Gy, and 20 to 40 Gy in 5 fractions, 3 fractions, and a single fraction, respectively. The median biologically effective dose (BED) using the universal survival model was 134.5 Gy. The 1-year LC rate after SAbR was 91.2% (95% confidence interval, 84.9%-95.0%; median follow-up, 16.7 months). Local failures were associated with prior radiation therapy (hazard ratio [HR], 10.49; P<.0001), palliative-intent radiation therapy (HR, 4.63; P=.0189), spinal location (HR, 5.36; P=.0041), previous systemic therapy status (0-1 vs >1; HR, 3.52; P=.0217), and BED <115 Gy (HR, 3.45; P=.0254). Dose received by 99% of the target volume was the strongest dosimetric predictor for LC. Upon multivariate analysis, dose received by 99% of the target volume greater than BED of 98.7 Gy and systemic therapy status remained significant (HR, 0.12 and 3.64, with P=.0014 and P=.0472, respectively). Acute and late grade 3 toxicities attributed to SAbR were observed in 3 patients (1.7%) and 5 patients (2.9%), respectively. Conclusions: SAbR demonstrated excellent LC of metastatic renal cell carcinoma with a favorable safety profile when an adequate dose and coverage were applied. Multimodality treatment with surgery should be considered for reirradiation or vertebral metastasis. A higher radiation dose may be required in patients who received previous systemic therapies.

• OSTI ID: 22649911
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 98, Issue 1; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CARCINOMAS
DOSIMETRY
GY RANGE 100-1000
GY RANGE 10-100
KIDNEYS
MULTIVARIATE ANALYSIS
PATIENTS
RADIATION DOSES
RADIOTHERAPY