Renal atrophy after stereotactic body radiotherapy for renal cell carcinoma

Takaya Yamamoto, Noriyuki Kadoya, Ken Takeda, Haruo Matsushita, Rei Umezawa, Kiyokazu Sato, Masaki Kubozono, Kengo Ito, Yojiro Ishikawa, Maiko Kozumi, Noriyoshi Takahashi, Yu Katagiri, Hiroshi Onishi, Keiichi Jingu

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Background: Renal atrophy is observed in an irradiated kidney. The aim of this study was to determine dose-volume histogram parameters and other factors that predict renal atrophy after 10-fraction stereotactic bodyradiotherapy (SBRT) for primary renal cell carcinoma (RCC). Methods: A total of 14 patients (11 males, 3 females) who received SBRT for RCC at Tohoku University Hospital between April 2010 and February 2014 were analyzed. The median serum creatinine level was 1.1mg/dl and two patients had a single kidney. Nine patients were implanted with fiducial markers. The median tumor diameter was 30mm. SBRT was delivered at 70Gy in 10 fractions for 7 tumors, at 60Gy in 10 fractions for 2 tumors, and at 50Gy in 10 fractions for 5 tumors with 6 and/or 15 MV X-ray using 5 to 8 multi-static beams. Renal atrophy was assessed using post-SBRT CT images after 12-24 months intervals. Correlations were examined by Spearman rank correlation analysis. Differences between two groups were evaluated by the Mann-Whitney test, and pairwise comparisons were made by the Wilcoxon signed-rank test. Results: The median tumor volume shrunk from 14.8cc to 10.6cc (p=0.12), and the median irradiated kidney volume changed from 160.4cc to 137.1cc (p<.01). The median peak creatinine level was 1.6mg/dl after treatment (p<.01). Percentage volumes of the irradiated kidney receiving at least 10Gy (V10, p=0.03), V20 (p<.01), V30(p<.01), V40 (p=0.01), mean irradiated kidney dose (p<.01), and magnitude of overlap between PTV and kidney volume (p=0.03) were significantly correlated with post-treatment irradiated kidney volume in percent, and V20-V30 had strong correlation (r<0.70, p<.01). Patients with implanted fiducial markers showed a significantly lower ratio of renal atrophy (p=0.02). Conclusions: Significant renal atrophic change was observed. Dose distribution of SBRT at 20-30Gy had a strong correlation with renal atrophy when irradiation was performed in 10 fractions.

Original languageEnglish
Article number72
JournalRadiation Oncology
Volume11
Issue number1
DOIs
Publication statusPublished - 2016 May 26

Keywords

  • Renal atrophy
  • Renal cell cancer
  • Renal remodeling
  • SRT
  • Stereotactic radiotherapy

ASJC Scopus subject areas

  • Oncology
  • Radiology Nuclear Medicine and imaging

Fingerprint Dive into the research topics of 'Renal atrophy after stereotactic body radiotherapy for renal cell carcinoma'. Together they form a unique fingerprint.

  • Cite this