Topics to be Discussed
description
Transcript of Topics to be Discussed
![Page 1: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/1.jpg)
Innovative Computerized Innovative Computerized Treatment Planning System for Treatment Planning System for Permanent Prostate ImplantsPermanent Prostate Implants
Eva K. Lee, Radiation Oncology, Emory University; Eva K. Lee, Radiation Oncology, Emory University; Industrial & Systems Engineering, Georgia Institute of Technology.Industrial & Systems Engineering, Georgia Institute of Technology.
![Page 2: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/2.jpg)
Topics to be Discussed
• Automated Treatment Planning System for Automated Treatment Planning System for Brachytherapy in Permanent Prostate Brachytherapy in Permanent Prostate ImplantsImplants
• MRS-image guided Dose-Escalation MRS-image guided Dose-Escalation Planning Planning
• Extended-time Dose Control and Planning Extended-time Dose Control and Planning Taking Edema Shrinkage and Seed Taking Edema Shrinkage and Seed Displacement into AccountDisplacement into Account
![Page 3: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/3.jpg)
Brachytherapy for Prostate Carcinoma
• Radiation therapy that involves the placement of radioactive sources permanently inside the prostate.
![Page 4: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/4.jpg)
Transperineal Implantation of Radionuclides using Transrectal
Ultrasound (TRUS) Device
![Page 5: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/5.jpg)
Part I:Part I:Automated Treatment Planning Automated Treatment Planning
System for BrachytherapySystem for Brachytherapy
![Page 6: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/6.jpg)
Computerized Optimization Approach
• Include strict dose bounds for different anatomies• Impose clinically desired properties • Superior plans / Time savings
– Can generate a plan within 5 minutes
• Allow intra-operative planning for clinicians– overcome current pre-planning problems– allow real-time alteration of plans due to unforeseen
implantation problems
• First-of-its-kind• Research tool to push frontier of understanding
![Page 7: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/7.jpg)
Manual Plan shows poor post-implant coverage & conformity (white curve represents contour of prostate
slice, green curve represents the 100% isodose curve)
![Page 8: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/8.jpg)
Optimized Plan from Automated System showssuperior coverage & conformity (white curve represents contour of prostate slice, green curve
represents the 100% isodose curve)
![Page 9: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/9.jpg)
Part II:Part II:MRS-image guided Dose-MRS-image guided Dose-
Escalation PlanningEscalation Planning
![Page 10: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/10.jpg)
MRS-Image Guided Planning
• Explore feasibility of designing treatment plans with localized escalated dose in identifiable tumor regions of the prostate and gauge the biological significance of doing so.
• Escalate dose in tumor regions within prostate identified by MRS-images
• Case study of a patient shows drastic improvement of tumor control probability from 65% to 95% in dose escalated plans
![Page 11: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/11.jpg)
Example of dose escalation around the tumor regionExample of dose escalation around the tumor region::
![Page 12: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/12.jpg)
Here the tumor spot is in the vicinity of the urethra: the Here the tumor spot is in the vicinity of the urethra: the dose received by the urethra is kept within strict pre-set dose received by the urethra is kept within strict pre-set levels and reasonable escalation is observed in the tumor levels and reasonable escalation is observed in the tumor area.area.
![Page 13: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/13.jpg)
Estimated Tumor Control Probability (TCP) Estimated Tumor Control Probability (TCP) values for 3 different tumor volumes: MRS-values for 3 different tumor volumes: MRS-
guided and standard plansguided and standard plans
MRS-guided plan appears consistently superior to MRS-guided plan appears consistently superior to the non-dose-escalated (standard) plan.the non-dose-escalated (standard) plan.
Table 3: Estimated TCP values (n = 1.36 109 cells, Prostate volume = 38.1 cm3)
Tumor volume
(cm3)
Standard plan
(Plan A)
MRS-guided plan
(Plan B)
Ratio of Plan B to
Plan A
1.36 0.649 0.943 1.45
2.35 0.650 0.965 1.48
3.71 0.761 0.948 1.25
![Page 14: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/14.jpg)
Part III:Part III:Extended-time Dose Control and Extended-time Dose Control and
Planning Taking Edema Planning Taking Edema Shrinkage and Seed Shrinkage and Seed
Displacement into AccountDisplacement into Account
![Page 15: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/15.jpg)
Automated Planning with Extended Dose Control
• Patient case studies reveal excessive irradiation to prostate exterior, urethra and rectum when no extended dosimetric constraints, seed displacement or gland shrinkage information are included in the planning process.
• Dosimetric control of irradiation to the prostate, urethra and rectum; seed displacement; and gland shrinkage information are incorporated into planning over the entire 30 day period.
![Page 16: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/16.jpg)
Automated Planning with Extended Dose Control: Findings
• Multi-period planning provides conformal dosimetry to the gland over a period of 30 days, and a reduction of over 21% of external normal tissue receiving excessive irradiation.
• Multi-period planning demonstrates the potential for urethra and rectum morbidity reduction without compromising local tumor control.
![Page 17: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/17.jpg)
The figure below shows a plot of coverage and conformity scores over the 30-day horizon for several multi-period plans. For comparison, the single-period EPV[0] plan's 30-day coverage and conformity plot is also shown. Note that while initial coverage is somewhat better for EPV[0] than for the multi-period plans, overall conformity for EPV[0] is much worse.The lines with values above (below) 1.0 on the vertical axis correspond to the conformity (coverage) indices for the six plans.
![Page 18: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/18.jpg)
Statistics over 30 day horizon for a signle-period model with urethra and rectum dose imposed at multiple times Urethra Dose Statistics Day (t) 0 6 12 18 24 30 % < 1.2D(t) 100 100 100 100 100 100 Max dose / (1.2 D(t))
0.94 0.99 0.99 1.0 0.99 1.0
Rectum Dose Statistics Day (t) 0 6 12 18 24 30 % < 0.8 D(t) 100 100 100 100 100 100 Max dose / (0.8 D(t))
0.94 0.94 0.95 0.96 0.97 1.0
.
Statistics over 30 day horizon for a single-period model with urethra and rectum dose imposed at time 0 Urethra Dose Statistics Day (t) 0 6 12 18 24 30 % < 1.2D(t) 100 33.33 22.22 22.22 22.22 11.11 Max dose / (1.2 D(t))
0.98 1.03 1.07 1.11 1.15 1.18
Rectum Dose Statistics Day (t) 0 6 12 18 24 30 % < 0.8 D(t) 100 70 60 60 60 60 Max dose / (0.8 D(t))
0.99 1.04 1.08 1.12 1.15 1.16
![Page 19: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/19.jpg)
References• E.K. Lee, M. Zaider, Intra-Operative Iterative Treatment-Plan Optimization
for Prostate Permanent Implants. 2nd International Innovative Solutions for Prostate Cancer Care meeting, 32-33, 2001.
• M. Zaider, E.K. Lee, MRS-guided Dose-Escalation Treatment Planning Optimization for Permanent Prostate Implants. 2nd International Innovative Solutions for Prostate Cancer Care meeting, 36, 2001.
• E.K. Lee, M. Zaider, Determining an Effective Planning Volume for Permanent Prostate Implants. International Journal of Radiation Oncology, Biology and Physics, 49(5) (2001), in print.
• M. Zaider, M. Zelefsky, E.K. Lee, K. Zakian, H.A. Amols, J. Dyke, J. Koutcher. Treatment Planning for Prostate Implants Using MR Spectroscopy Imaging. International Journal of Radiation Oncology, Biology and Physics, 47(4): 1085-96 (2000)
• E.K. Lee, R. Gallagher, M. Zaider, Planning implants of radionuclides for the treatment of prostate cancer: an application of mixed integer programming. Optima (Mathematical Programming Society Newsletter), feature article, 1999; 61: 1 – 10.
![Page 20: Topics to be Discussed](https://reader035.fdocuments.us/reader035/viewer/2022070404/56813c71550346895da6069f/html5/thumbnails/20.jpg)
References• C.S. Wuu, R.D. Ennis, P.B. Schiff, E.K. Lee, M. Zaider, Dosimetric and
Volumetric Criteria for Selecting a Source Type I-125 or Pd-103 and Source Activity in the Presence of Irregular Seed Placement in Permanent Prostate Implants. International Journal of Radiation Oncology, Biology and Physics, 47: 815-820 (2000).
• E.K. Lee, R. Gallagher, D. Silvern, C.S. Wuu, and M. Zaider, Treatment Planning for Brachytherapy: An Integer Programming Model, Two Computational Approaches and Experiments with Permanent Prostate Implant Planning. Physics in Medicine and Biology Vol. 44 (1), pp.~145-165, 1999.
• D. Silvern, E.K. Lee, R. Gallagher, L.G. Stabile, R.D. Ennis, C.R. Moorthy, and M. Zaider, Treatment Planning for Permanent Prostate Implants: Genetic Algorithm versus Integer Programming. Medical & Biological Engineering & Computing, vol.~35, Supplement Part 2, 1997.
• R. Gallagher, E.K. Lee, Mixed Integer Programming Optimization Models for Brachytherapy Treatment Planning. In: Daniel R. Masys, Ed. Proceedings of the 1997 American Medical Informatics Association Annual Fall Symposium, 278-282, 1997.