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Interfraction variation and dosimetric changes during image-guided radiation therapy in prostate cancer patients

  • Fuchs, Frederik (Department of Radiation Oncology, Technical University of Munich (TUM)) ;
  • Habl, Gregor (Department of Radiation Oncology, Technical University of Munich (TUM)) ;
  • Devecka, Michal (Department of Radiation Oncology, Technical University of Munich (TUM)) ;
  • Kampfer, Severin (Department of Radiation Oncology, Technical University of Munich (TUM)) ;
  • Combs, Stephanie E. (Department of Radiation Oncology, Technical University of Munich (TUM)) ;
  • Kessel, Kerstin A. (Department of Radiation Oncology, Technical University of Munich (TUM))
  • Received : 2018.11.20
  • Accepted : 2019.03.15
  • Published : 2019.06.30

Abstract

Purpose: The aim of this study was to identify volume changes and dose variations of rectum and bladder during radiation therapy in prostate cancer (PC) patients. Materials and Methods: We analyzed 20 patients with PC treated with helical tomotherapy. Daily image guidance was performed. We re-contoured the entire bladder and rectum including its contents as well as the organ walls on megavoltage computed tomography once a week. Dose variations were analyzed by means of Dmedian, Dmean, Dmax, V10 to V75, as well as the organs at risk (OAR) volume. Further, we investigated the correlation between volume changes and changes in Dmean of OAR. Results: During treatment, the rectal volume ranged from 62% to 223% of its initial volume, the bladder volume from 22% to 375%. The average Dmean ranged from 87% to 118% for the rectum and 58% to 160% for the bladder. The Pearson correlation coefficients between volume changes and corresponding changes in Dmean were -0.82 for the bladder and 0.52 for the rectum. The comparison of the dose wall histogram (DWH) and the dose volume histogram (DVH) showed that the DVH underestimates the percentage of the rectal and bladder volume exposed to the high dose region. Conclusion: Relevant variations in the volume of OAR and corresponding dose variations can be observed. For the bladder, an increase in the volume generally leads to lower doses; for the rectum, the correlation is weaker. Having demonstrated remarkable differences in the dose distribution of the DWH and the DVH, the use of DWHs should be considered.

References

  1. Kupelian PA, Langen KM, Zeidan OA, et al. Daily variations in delivered doses in patients treated with radiotherapy for localized prostate cancer. Int J Radiat Oncol Biol Phys 2006;66:876-82. https://doi.org/10.1016/j.ijrobp.2006.06.011
  2. Chen L, Paskalev K, Xu X, et al. Rectal dose variation during the course of image-guided radiation therapy of prostate cancer. Radiother Oncol 2010;95:198-202. https://doi.org/10.1016/j.radonc.2010.02.023
  3. Roeske JC, Forman JD, Mesina CF, et al. Evaluation of changes in the size and location of the prostate, seminal vesicles, bladder, and rectum during a course of external beam radiation therapy. Int J Radiat Oncol Biol Phys 1995;33:1321-9. https://doi.org/10.1016/0360-3016(95)00225-1
  4. Tsai CL, Wu JK, Wang CW, Hsu FM, Lai MK, Cheng JC. Using cone-beam computed tomography to evaluate the impact of bladder filling status on target position in prostate radiotherapy. Strahlenther Onkol 2009;185:588-95. https://doi.org/10.1007/s00066-009-1987-7
  5. Langen KM, Jones DT. Organ motion and its management. Int J Radiat Oncol Biol Phys 2001;50:265-78. https://doi.org/10.1016/S0360-3016(01)01453-5
  6. Verma V, Chen S, Zhou S, Enke CA, Wahl AO. Prostate bed target interfractional motion using RTOG consensus definitions and daily CT on rails: does target motion differ between superior and inferior portions of the clinical target volume? Strahlenther Onkol 2017;193:38-45. https://doi.org/10.1007/s00066-016-1077-6
  7. Huang E, Dong L, Chandra A, et al. Intrafraction prostate motion during IMRT for prostate cancer. Int J Radiat Oncol Biol Phys 2002;53:261-8. https://doi.org/10.1016/S0360-3016(02)02738-4
  8. Zelefsky MJ, Fuks Z, Hunt M, et al. High-dose intensity modulated radiation therapy for prostate cancer: early toxicity and biochemical outcome in 772 patients. Int J Radiat Oncol Biol Phys 2002;53:1111-6. https://doi.org/10.1016/S0360-3016(02)02857-2
  9. Zelefsky MJ, Kollmeier M, Cox B, et al. Improved clinical outcomes with high-dose image guided radiotherapy compared with non-IGRT for the treatment of clinically localized prostate cancer. Int J Radiat Oncol Biol Phys 2012;84:125-9. https://doi.org/10.1016/j.ijrobp.2011.11.047
  10. Sanda MG, Dunn RL, Michalski J, et al. Quality of life and satisfaction with outcome among prostate-cancer survivors. N Engl J Med 2008;358:1250-61. https://doi.org/10.1056/NEJMoa074311
  11. Ting JY, Wu X, Fiedler JA, Yang C, Watzich ML, Markoe A. Dosevolume histograms for bladder and rectum. Int J Radiat Oncol Biol Phys 1997;38:1105-11. https://doi.org/10.1016/S0360-3016(97)00312-X
  12. Tucker SL, Dong L, Cheung R, et al. Comparison of rectal dosewall histogram versus dose-volume histogram for modeling the incidence of late rectal bleeding after radiotherapy. Int J Radiat Oncol Biol Phys 2004;60:1589-601. https://doi.org/10.1016/j.ijrobp.2004.07.712
  13. Huang TC, Chou KT, Yang SN, Chang CK, Liang JA, Zhang G. Fractionated changes in prostate cancer radiotherapy using cone-beam computed tomography. Med Dosim 2015;40:222-5. https://doi.org/10.1016/j.meddos.2014.12.003
  14. Chen Z, Yang Z, Wang J, Hu W. Dosimetric impact of different bladder and rectum filling during prostate cancer radiotherapy. Radiat Oncol 2016;11:103. https://doi.org/10.1186/s13014-016-0681-z
  15. Jameson MG, De Leon J, Windsor AA, et al. Endorectal balloons in the post prostatectomy setting: do gains in stability lead to more predictable dosimetry? Radiother Oncol 2013;109:493-7. https://doi.org/10.1016/j.radonc.2013.08.024
  16. de Leon JF, Jameson MG, Windsor A, et al. Superior target volume and organ stability with the use of endorectal balloons in post-prostatectomy radiotherapy. J Med Imaging Radiat Oncol 2015;59:507-13. https://doi.org/10.1111/1754-9485.12300
  17. Scaife J, Harrison K, Romanchikova M, et al. Random variation in rectal position during radiotherapy for prostate cancer is two to three times greater than that predicted from prostate motion. Br J Radiol 2014;87:20140343. https://doi.org/10.1259/bjr.20140343
  18. Maggio A, Carillo V, Cozzarini C, et al. Impact of the radiotherapy technique on the correlation between dosevolume histograms of the bladder wall defined on MRI imaging and dose-volume/surface histograms in prostate cancer patients. Phys Med Biol 2013;58:N115-23. https://doi.org/10.1088/0031-9155/58/7/N115
  19. Guckenberger M, Meyer J, Baier K, Vordermark D, Flentje M. Distinct effects of rectum delineation methods in 3D-conformal vs. IMRT treatment planning of prostate cancer. Radiat Oncol 2006;1:34. https://doi.org/10.1186/1748-717X-1-34
  20. Carillo V, Cozzarini C, Chietera A, et al. Correlation between surrogates of bladder dosimetry and dose-volume histograms of the bladder wall defined on MRI in prostate cancer radiotherapy. Radiother Oncol 2012;105:180-3. https://doi.org/10.1016/j.radonc.2012.10.001