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Radiobiologically optimized couch shift: A new localization paradigm using cone-beam CT for prostate radiotherapy
1.M. J. Zelefsky, D. Crean, G. S. Mageras, O. Lyass, L. Happersett, C. C. Ling, S. A. Leibel, Z. Fuks, S. Bull, H. M. Kooy, M. van Herk, and G. J. Kutcher, “Quantification and predictors of prostate position variability in 50 patients evaluated with multiple CT scans during conformal radiotherapy,” Radiother. Oncol. 50, 225–234 (1999).
2.M. van Herk, P. Remeijer, C. Rasch, and J. V. Lebesque, “The probability of correct target dosage: Dose-population histograms for deriving treatment margins in radiotherapy,” Int. J. Radiat. Oncol., Biol., Phys. 47, 1121–1135 (2000).
3.J. C. O’Daniel, L. Dong, L. Zhang, R. de Crevoisier, H. Wang, A. K. Lee, R. Cheung, S. L. Tucker, R. J. Kudchadker, M. D. Bonnen, J. D. Cox, R. Mohan, and D. A. Kuban, “Dosimetric comparison of four target alignment methods for prostate cancer radiotherapy,” Int. J. Radiat. Oncol., Biol., Phys. 66, 883–891 (2006).
4.E. J. Rijkhorst, A. Lakeman, J. Nijkamp, J. de Bois, M. van Herk, J. V. Lebesque, and J. J. Sonke, “Strategies for online organ motion correction for intensity-modulated radiotherapy of prostate cancer: Prostate, rectum, and bladder dose effects,” Int. J. Radiat. Oncol., Biol., Phys. 75, 1254–1260 (2009).
5.T. F. Mutanga, H. C. de Boer, G. J. van der Wielen, M. S. Hoogeman, L. Incrocci, and B. J. Heijmen, “Margin evaluation in the presence of deformation, rotation, and translation in prostate and entire seminal vesicle irradiation with daily marker-based setup corrections,” Int. J. Radiat. Oncol., Biol., Phys. 81, 1160–1167 (2011).
6.D. Yan, D. Lockman, D. Brabbins, L. Tyburski, and A. Martinez, “An off-line strategy for constructing a patient-specific planning target volume in adaptive treatment process for prostate cancer,” Int. J. Radiat. Oncol., Biol., Phys. 48, 289–302 (2000).
7.R. Mohan, X. Zhang, H. Wang, Y. Kang, X. Wang, H. Liu, K. K. Ang, D. Kuban, and L. Dong, “Use of deformed intensity distributions for on-line modification of image-guided IMRT to account for interfractional anatomic changes,” Int. J. Radiat. Oncol., Biol., Phys. 61, 1258–1266 (2005).
8.E. E. Ahunbay, C. Peng, G. P. Chen, S. Narayanan, C. Yu, C. Lawton, and X. A. Li, “An on-line replanning scheme for interfractional variations,” Med. Phys. 35, 3607–3615 (2008).
9.X. A. Li, Q. Wu, and C. G. Orton, “Point/counterpoint. Online adaptive planning for prostate cancer radiotherapy is necessary and ready now,” Med. Phys. 41, 080601 (3pp.) (2014).
10.S. J. Gardner, N. Wen, J. Kim, C. Liu, D. Pradhan, I. Aref, R. Cattaneo, S. Vance, B. Movsas, I. J. Chetty, and M. A. Elshaikh, “Contouring variability of human- and deformable-generated contours in radiotherapy for prostate cancer,” Phys. Med. Biol. 60, 4429–4447 (2015).
11.J. O. Deasy, A. I. Blanco, and V. H. Clark, “ cerr: A computational environment for radiotherapy research,” Med. Phys. 30, 979–985 (2003).
12.A. Niemierko, “Reporting and analyzing dose distributions: A concept of equivalent uniform dose,” Med. Phys. 24, 103–110 (1997).
13.J. M. Michalski, H. Gay, A. Jackson, S. L. Tucker, and J. O. Deasy, “Radiation dose-volume effects in radiation-induced rectal injury,” Int. J. Radiat. Oncol., Biol., Phys. 76, S123–S129 (2010).
14.M. R. Cheung, S. L. Tucker, L. Dong, R. de Crevoisier, A. K. Lee, S. Frank, R. J. Kudchadker, H. Thames, R. Mohan, and D. Kuban, “Investigation of bladder dose and volume factors influencing late urinary toxicity after external beam radiotherapy for prostate cancer,” Int. J. Radiat. Oncol., Biol., Phys. 67, 1059–1065 (2007).
15.Q. Wu, D. Djajaputra, H. H. Liu, L. Dong, R. Mohan, and Y. Wu, “Dose sculpting with generalized equivalent uniform dose,” Med. Phys. 32, 1387–1396 (2005).
17.N. Wen, C. Glide-Hurst, T. Nurushev, L. Xing, J. Kim, H. Zhong, D. Liu, M. Liu, J. Burmeister, B. Movsas, and I. J. Chetty, “Evaluation of the deformation and corresponding dosimetric implications in prostate cancer treatment,” Phys. Med. Biol. 57, 5361–5379 (2012).
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To present a novel positioning strategy which optimizes radiation delivery by utilizing radiobiological response knowledge and evaluate its use during prostate external beam radiotherapy.
Five patients with low or intermediate risk prostate cancer were evaluated retrospectively in this IRB-approved study. For each patient, a VMAT plan with one 358° arc was generated on the planning CT (PCT) to deliver 78 Gy in 39 fractions. Five representative pretreatment cone beam CTs (CBCT) were selected for each patient. The CBCT
images were registered to PCT by a human observer, which consisted of an initial automated registration with three degrees-of-freedom, followed by manual adjustment for agreement at the prostate/rectal wall interface. To determine the optimal treatment position for each CBCT, a search was performed centering on the observer-matched position (OM-position) utilizing a score function based on radiobiological and dosimetric indices (EUDprostate, D99prostate, NTCPrectum, and NTCPbladder) for the prostate, rectum, and bladder. We termed the optimal treatment position the radiobiologically optimized couch shift position (ROCS-position).
The dosimetric indices, averaged over the five patients’ treatment plans, were (mean ± SD) 79.5 ± 0.3 Gy (EUDprostate), 78.2 ± 0.4 Gy (D99prostate), 11.1% ± 2.7% (NTCPrectum), and 46.9% ± 7.6% (NTCPbladder). The corresponding values from CBCT at the OM-positions were 79.5 ± 0.6 Gy (EUDprostate), 77.8 ± 0.7 Gy (D99prostate), 12.1% ± 5.6% (NTCPrectum), and 51.6% ± 15.2% (NTCPbladder), respectively. In comparison, from CBCT at the ROCS-positions, the dosimetric indices were 79.5 ± 0.6 Gy (EUDprostate), 77.3 ± 0.6 Gy (D99prostate), 8.0% ± 3.3% (NTCPrectum), and 46.9% ± 15.7% (NTCPbladder). Excessive NTCPrectum was observed on Patient 5 (19.5% ± 6.6%) corresponding to localization at OM-position, compared to the planned value of 11.7%. This was mitigated with radiobiologically optimized localization, resulting in a reduced NTCPrectum value of 11.3% ± 3.5%. Overall, the treatment position optimization resulted in similar target dose coverage with reduced risk to rectum.
These encouraging results illustrate the potential advantage of applying radiobiologically optimized correction for online image-guided radiotherapy of prostate patients.
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