Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-10T12:19:22.296Z Has data issue: false hasContentIssue false

Radiotherapy treatment planning for prostate and nodes using variable planning ring

Published online by Cambridge University Press:  23 December 2019

Poonam Yadav*
Affiliation:
Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
Yue Yan
Affiliation:
Department of Radiation Oncology, St Jude Children’s Research Hospital, Memphis, TN, USA
Bhudatt R. Paliwal
Affiliation:
Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
*
Author for correspondence: Poonam Yadav, Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, K4/B74, Madison, WI, USA. Tel: 001 608-235-2594. Fax: 001 608-263-0990. E-mail: yadav@humonc.wisc.edu

Abstract

Background:

Prostate cancer is one of the most common solid malignancies and has a high morbidity rate. The uncertainty of the prostate location compromises the overall treatment plan optimisation. To account for the location uncertainty, the radiation oncologist needs to expand the margin of the planning target volume (PTV), which may increase the radiation toxicity to organs in proximity.

Materials and methods:

In this study, we investigated the quality of treatment plans for a patient with different ring sizes (2 and 3 cm). A small ring-shaped structure circumferentially around the PTV helps in defining the location of PTV. Prostate and pelvic node plans were analysed with dose prescription to 99% of PTV.

Results:

Additional ring-shaped structures led to more conformal dose coverage for target with reduced radiation side effects to nearby organ at risk (OAR). Expected treatment time was slightly higher for 2 cm ring compared to 3 cm ring. In case of prostate, expected duration was 4% higher, while for node plan, expected duration for 2 cm ring was 16% higher compared to 3 cm ring plan.

Conclusions:

It was observed that using a smaller size ring can lead to improved dose sparing to OAR with same target coverage as with larger dimension ring. The composite plans do not show any clinically significant difference in dose to OARs.

Type
Case Study
Copyright
© Cambridge University Press 2019

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Edwards, BK, Noone, AM, Mariotto, AB et al. Annual Report to the Nation on the status of cancer, 1975‐2010, featuring prevalence of comorbidity and impact on survival among persons with lung, colorectal, breast, or prostate cancer. Cancer 2014; 120 (9): 12901314.CrossRefGoogle ScholarPubMed
Walsh, PC, DeWeese, TL, Eisenberger, MA. Localized prostate cancer. N Engl J Med 2007; 357: 26962705.Google ScholarPubMed
Suzuki, K, Nishioka, T, Homma, A et al. Value of fluorodeoxyglucose positron emission tomography before radiotherapy for head and neck cancer: does the standardized uptake value predict treatment outcome? Jpn J Radiol 2009; 27: 237242.Google ScholarPubMed
Deloar, HM, Kunieda, E, Kawase, T et al. Investigations of different kilovoltage X-ray energy for three-dimensional converging stereotactic radiotherapy system: Monte Carlo simulations with CT data. Med Phys 2006; 33: 46354642.CrossRefGoogle ScholarPubMed
Hamamoto, Y, Inata, H, Sodeoka, N et al. Observation of intrafraction prostate displacement through the course of conventionally fractionated radiotherapy for prostate cancer. Jpn J Radiol 2015; 33: 187193.CrossRefGoogle ScholarPubMed
Sze, HC, Lee, MC, Hung, WM, Yau, TK, Lee, AW. RapidArc radiotherapy planning for prostate cancer: single-arc and double-arc techniques vs. intensity-modulated radiotherapy. Med Dosim 2012; 37: 8791.Google ScholarPubMed
Yoshimura, R, Iwata, M, Shibuya, H, Sakai, Y, Kihara, K. Acute and late genitourinary toxicity of conformal radiotherapy for prostate cancer. Radiat Med 2006; 24: 553559.CrossRefGoogle ScholarPubMed
Wojcieszynski, AP, Olson, AK, Rong, Y, Kimple, RJ, Yadav, P. Acute toxicity from breast cancer radiation using helical tomotherapy with a simultaneous integrated boost. Technol Cancer Res Treat 2015; 15 (2): 257265.CrossRefGoogle ScholarPubMed
Nagashima, T, Sakakibara, M, Sangai, T, Kazama, T, Fujimoto, H, Miyazaki, M. Surrounding rim formation and reduction in size after radiofrequency ablation for primary breast cancer. Jpn J Radiol 2009; 27: 197204.CrossRefGoogle ScholarPubMed
Guckenberger, M, Sweeney, RA. Reduced normal tissue doses through advanced technology. In: Nieder, C, Langendijk, J (eds). Re-irradiation: New Frontiers. Berlin Heidelberg: Springer-Verlag, 2011; 5984.Google Scholar