"Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has."

Margaret Mead
Case report
peer-reviewed

A Dosimetric Comparison of Intensity-Modulated Proton Therapy, Volumetric-Modulated Arc Therapy, and 4π Non-Coplanar Intensity-Modulated Radiation Therapy for a Patient with Parameningeal Rhabdomyosarcoma



Abstract

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and manifests as two major histological subtypes: embryonal and alveolar. The five-year local failure rate for RMS at parameningeal sites (middle ear, mastoid region, nasal cavity, etc.) is around 17% despite multiple Intergroup Rhabdomyosarcoma Study Group (IRS) trials conducted to determine the optimal radiation treatment regimen. This case report explores the use of intensity-modulated proton therapy (IMPT) for a 10-year-old child who presented with left eye irritation, facial pain, and headaches and was found to have an alveolar parameningeal rhabdomyosarcoma. He received systemic therapy as well as radiation therapy to 5,640 cGy and 4,320 cGy over 24 fractions, prescribed for gross tumor extension and adjacent high-risk involved sites, respectively, via simultaneous integrated boost. Approximately two years following treatment, the patient has had no recurrence of his RMS with no distant metastases. In addition, his presenting symptom of left eye irritation has improved. His only side effect from radiation at this point is short stature, possibly due to growth hormone deficiency. The patient’s IMPT plan was compared with volumetric-modulated arc therapy (VMAT) and 4π non-coplanar intensity-modulated radiation therapy (IMRT) plans, and comparisons of isodose lines show decreased dose to the distal brain tissue with preserved target conformality by IMPT. IMPT also allowed for increased sparing of the patient's retina, lens, and lacrimal gland. All radiation plans achieved conformal dose coverage to the planning/scanning target volumes, while the IMPT plan is potentially better at sparing the patient from developing long-term optic apparatus side effects and neurocognitive defects. In this case, IMPT is comparable, if not favorable, when long-term side effects can be reduced while maintaining dose conformality and local control.



Want to read more?

Create a free account to continue reading this article.

Already a member? Login.



Case report
peer-reviewed

A Dosimetric Comparison of Intensity-Modulated Proton Therapy, Volumetric-Modulated Arc Therapy, and 4π Non-Coplanar Intensity-Modulated Radiation Therapy for a Patient with Parameningeal Rhabdomyosarcoma


Author Information

Tiffany W. Chen

Department of Radiation Oncology, UT Health San Antonio Cancer Center

Julian Sison Corresponding Author

Robert Wood Johnson Medical School

Becky Lee

David Geffen School of Medicine, UCLA

Arthur J. Olch

Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA

Andrew Chang

Department of Radiation Oncology, Scripps Proton Therapy Center

Annelise Giebeler

Radiation Oncology, Scripps Proton Therapy Center

Kenneth Wong

Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA


Ethics Statement and Conflict of Interest Disclosures

Human subjects: Consent was obtained by all participants in this study. Conflicts of interest: The authors have declared that no conflicts of interest exist.


Case report
peer-reviewed

A Dosimetric Comparison of Intensity-Modulated Proton Therapy, Volumetric-Modulated Arc Therapy, and 4π Non-Coplanar Intensity-Modulated Radiation Therapy for a Patient with Parameningeal Rhabdomyosarcoma


Figures etc.

Share
Case report
peer-reviewed

A Dosimetric Comparison of Intensity-Modulated Proton Therapy, Volumetric-Modulated Arc Therapy, and 4π Non-Coplanar Intensity-Modulated Radiation Therapy for a Patient with Parameningeal Rhabdomyosarcoma

  • Author Information
    Tiffany W. Chen

    Department of Radiation Oncology, UT Health San Antonio Cancer Center

    Julian Sison Corresponding Author

    Robert Wood Johnson Medical School

    Becky Lee

    David Geffen School of Medicine, UCLA

    Arthur J. Olch

    Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA

    Andrew Chang

    Department of Radiation Oncology, Scripps Proton Therapy Center

    Annelise Giebeler

    Radiation Oncology, Scripps Proton Therapy Center

    Kenneth Wong

    Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA


    Ethics Statement and Conflict of Interest Disclosures

    Human subjects: Consent was obtained by all participants in this study. Conflicts of interest: The authors have declared that no conflicts of interest exist.

    Acknowledgements


    Article Information

    Published: September 10, 2017

    DOI

    10.7759/cureus.1673

    Cite this article as:

    Chen T W, Sison J, Lee B, et al. (September 10, 2017) A Dosimetric Comparison of Intensity-Modulated Proton Therapy, Volumetric-Modulated Arc Therapy, and 4π Non-Coplanar Intensity-Modulated Radiation Therapy for a Patient with Parameningeal Rhabdomyosarcoma . Cureus 9(9): e1673. doi:10.7759/cureus.1673

    Publication history

    Received by Cureus: August 08, 2017
    Peer review began: August 16, 2017
    Peer review concluded: September 07, 2017
    Published: September 10, 2017

    Copyright

    © Copyright 2017
    Chen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 3.0., which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

    License

    This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and manifests as two major histological subtypes: embryonal and alveolar. The five-year local failure rate for RMS at parameningeal sites (middle ear, mastoid region, nasal cavity, etc.) is around 17% despite multiple Intergroup Rhabdomyosarcoma Study Group (IRS) trials conducted to determine the optimal radiation treatment regimen. This case report explores the use of intensity-modulated proton therapy (IMPT) for a 10-year-old child who presented with left eye irritation, facial pain, and headaches and was found to have an alveolar parameningeal rhabdomyosarcoma. He received systemic therapy as well as radiation therapy to 5,640 cGy and 4,320 cGy over 24 fractions, prescribed for gross tumor extension and adjacent high-risk involved sites, respectively, via simultaneous integrated boost. Approximately two years following treatment, the patient has had no recurrence of his RMS with no distant metastases. In addition, his presenting symptom of left eye irritation has improved. His only side effect from radiation at this point is short stature, possibly due to growth hormone deficiency. The patient’s IMPT plan was compared with volumetric-modulated arc therapy (VMAT) and 4π non-coplanar intensity-modulated radiation therapy (IMRT) plans, and comparisons of isodose lines show decreased dose to the distal brain tissue with preserved target conformality by IMPT. IMPT also allowed for increased sparing of the patient's retina, lens, and lacrimal gland. All radiation plans achieved conformal dose coverage to the planning/scanning target volumes, while the IMPT plan is potentially better at sparing the patient from developing long-term optic apparatus side effects and neurocognitive defects. In this case, IMPT is comparable, if not favorable, when long-term side effects can be reduced while maintaining dose conformality and local control.



Want to read more?

Create a free account to continue reading this article.

Already a member? Login.



Tiffany W. Chen, Medical Student

Department of Radiation Oncology, UT Health San Antonio Cancer Center

Julian Sison, Medical Student

Robert Wood Johnson Medical School

For correspondence:
js2217@rwjms.rutgers.edu

Becky Lee

David Geffen School of Medicine, UCLA

Arthur J. Olch

Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA

Andrew Chang

Department of Radiation Oncology, Scripps Proton Therapy Center

Annelise Giebeler

Radiation Oncology, Scripps Proton Therapy Center

Kenneth Wong

Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA

Tiffany W. Chen, Medical Student

Department of Radiation Oncology, UT Health San Antonio Cancer Center

Julian Sison, Medical Student

Robert Wood Johnson Medical School

For correspondence:
js2217@rwjms.rutgers.edu

Becky Lee

David Geffen School of Medicine, UCLA

Arthur J. Olch

Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA

Andrew Chang

Department of Radiation Oncology, Scripps Proton Therapy Center

Annelise Giebeler

Radiation Oncology, Scripps Proton Therapy Center

Kenneth Wong

Department of Radiation Oncology, Keck School of Medicine of the University of Southern California, Los Angeles, CA