A comparative dosimetric analysis of virtual stereotactic body radiotherapy to high-dose-rate monotherapy for intermediate-risk prostate cancer Journal Article

Authors: Spratt, D. E.; Scala, L. M.; Folkert, M.; Voros, L.; Cohen, G. N.; Happersett, L.; Katsoulakis, E.; Zelefsky, M. J.; Kollmeier, M. A.; Yamada, Y.
Article Title: A comparative dosimetric analysis of virtual stereotactic body radiotherapy to high-dose-rate monotherapy for intermediate-risk prostate cancer
Abstract: Purpose: Stereotactic body radiotherapy (SBRT) is being used with increasing frequency as definitive treatment of early stage prostate cancer. Much of the justification for its adoption was derived from earlier clinical results using high-dose-rate (HDR) brachytherapy. We determine whether HDR's dosimetry can be achieved by virtual SBRT. Methods and Materials: Patients with intermediate-risk prostate cancer on a prospective trial evaluating the efficacy of HDR monotherapy treated to dose of 9.5. Gy. ×. 4 fractions were used for this study. A total of 5 patients were used in this analysis. Virtual SBRT plans were developed to reproduce the planning target volume (PTV) HDR dose distributions. Both normal tissue- and PTV-prioritized plans were generated. Results: From the normal tissue-prioritized plan, HDR and virtual SBRT achieved similar PTV V100 (93.8% vs. 93.1%, p=0.20) and V150 (40.3% vs. 42.9%, p=0.69) coverage. However, the PTV V200 was not attainable with SBRT (15.2% vs. 0.0%, p<0.001). The rectal Dmax was significantly lower with HDR (94.2% vs. 99.42%, p=0.05). The rectal D2 cc was also lower (60.8% vs. 71.1%, p=0.07). Difference in D1 cc urethral dose was not significantly different (87.7% vs. 75.2%, p=0.33). Comparing the PTV-prioritized plans, the rectal Dmax (94.2% vs. 111.1%, p=0.05) and mean dose (27.1% vs. 33.3%, p=0.03) were significantly higher using SBRT, and the rectal D2 cc was higher using SBRT (60.8% vs. 81.8%, p=0.07). Conclusions: HDR achieves significantly higher intraprostatic doses while achieving a lower maximum rectal dose compared with our virtual SBRT treatment planning. Future studies should compare clinical outcomes and toxicity between these modalities. © 2013 American Brachytherapy Society.
Keywords: clinical article; controlled study; human tissue; monotherapy; radiation dose; prostate cancer; dosimetry; brachytherapy; stereotactic body radiotherapy; stereotactic body radiation therapy; radiation dose distribution; iridium 192; urethra; rectum; bladder; high-dose rate
Journal Title: Brachytherapy
Volume: 12
Issue: 5
ISSN: 1538-4721
Publisher: Elsevier Science, Inc.  
Date Published: 2013-10-01
Start Page: 428
End Page: 433
Language: English
DOI: 10.1016/j.brachy.2013.03.003
PROVIDER: scopus
PUBMED: 23622710
Notes: --- - "Export Date: 1 October 2013" - "CODEN: BRACC" - "Source: Scopus"
Altmetric Score
MSK Authors
  1. Michael J Zelefsky
    624 Zelefsky
  2. Yoshiya Yamada
    359 Yamada
  3. Michael Ryan Folkert
    36 Folkert
  4. Laszlo Voros
    13 Voros
  5. Gilad N Cohen
    132 Cohen
  6. Marisa A Kollmeier
    146 Kollmeier
  7. Lawrence Matthew Scala
    6 Scala
  8. Daniel Eidelberg Spratt
    83 Spratt