Consensus Guidelines for Delineation of Clinical Target Volumes for Intensity-Modulated Radiotherapy for Intact Cervical Cancer: An Update

Emma C Fields; Walter R Bosch; Kevin V Albuquerque; Rohini Bhatia; Junzo Chino; Brandon Dyer; Beth Erickson; Denise Fabian; David Gaffney; Scott Glaser; Kathy Han; Lara Hathout; I-Chow Hsu; Naresh Jegadeesh; Jenna Kahn; Elizabeth Kidd; Ann Klopp; Eric Leung; Lilie Lin; Michelle Ludwig; Tianjun Ma; Loren Mell; Jyoti Mayadev; Ivy Petersen; Lorraine Portelance; Dominique Rash; Neil Taunk; Akila Viswanathan; Aaron Wolfson; Catheryn Yashar; Anamaria Yeung; Emi Yoshida; Christine M Fisher

doi:10.1016/j.prro.2024.11.004

Consensus Guidelines for Delineation of Clinical Target Volumes for Intensity-Modulated Radiotherapy for Intact Cervical Cancer: An Update

Pract Radiat Oncol. 2024 Nov 13:S1879-8500(24)00305-9. doi: 10.1016/j.prro.2024.11.004. Online ahead of print.

Authors

Emma C Fields¹, Walter R Bosch², Kevin V Albuquerque³, Rohini Bhatia⁴, Junzo Chino⁵, Brandon Dyer⁶, Beth Erickson⁷, Denise Fabian⁸, David Gaffney⁹, Scott Glaser¹⁰, Kathy Han¹¹, Lara Hathout¹², I-Chow Hsu¹³, Naresh Jegadeesh¹⁴, Jenna Kahn¹⁵, Elizabeth Kidd¹⁶, Ann Klopp¹⁷, Eric Leung¹¹, Lilie Lin¹⁷, Michelle Ludwig¹⁸, Tianjun Ma¹⁹, Loren Mell²⁰, Jyoti Mayadev²⁰, Ivy Petersen²¹, Lorraine Portelance²², Dominique Rash²⁰, Neil Taunk²³, Akila Viswanathan⁴, Aaron Wolfson²², Catheryn Yashar²⁰, Anamaria Yeung²⁴, Emi Yoshida¹³, Christine M Fisher²⁵

Affiliations

¹ Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia, USA. Electronic address: [email protected].
² Department of Radiation Oncology, Washington University, St. Louis, Missouri, USA.
³ Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas, USA.
⁴ Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins, Baltimore, Maryland, USA.
⁵ Department of Radiation Oncology, Duke University, Durham, North Carolina, USA.
⁶ Department of Radiation Oncology, University of Washington, Seattle, Washington, USA.
⁷ Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
⁸ Department of Radiation Oncology, University of Kentucky, Lexington, Kentucky, USA.
⁹ Department of Radiation Oncology, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, USA.
¹⁰ Department of Radiation Oncology, City of Hope, Duarte, California, USA.
¹¹ Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada.
¹² Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA.
¹³ Department of Radiation Oncology, University of California San Francisco, San Francisco, California, USA.
¹⁴ Department of Radiation Oncology, Cook County Health, Chicago, Illinois, USA.
¹⁵ Department of Radiation Oncology, Kaiser Permanente NW Region, Portland, Oregon, USA.
¹⁶ Department of Radiation Oncology, Stanford University, Palo Alto, California, USA.
¹⁷ Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
¹⁸ Department of Radiation Oncology, Baylor College of Medicine, Houston, Texas, USA.
¹⁹ Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia, USA.
²⁰ Department of Radiation Oncology, University of California San Diego, San Diego, California, USA.
²¹ Department of Radiation Oncology, Mayo Clinic Comprehensive Cancer Center, Rochester, Minnesota, USA.
²² Department of Radiation Oncology, University of Miami Health System, Miami, Florida, USA.
²³ Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
²⁴ Department of Radiation Oncology, University of Florida, Gainesville, Florida, USA.
²⁵ Department of Radiation Oncology, University of Colorado, Aurora, Colorado, USA.

PMID: 39547646
DOI: 10.1016/j.prro.2024.11.004

Abstract

Purpose: Accurate target delineation is essential when using intensity-modulated radiotherapy (IMRT) for intact cervical cancer. In 2011, the Radiation Therapy Oncology Group (RTOG) published a consensus guideline using magnetic resonance imaging (MRI). The current project expands on the previous atlas by including computed tomography (CT)-based contours, contours with MRI and positron- emission- tomography (PET) registrations, the addition of common and complex scenarios, and to incorporate information on simulation and treatment planning techniques.

Methods and materials: Twenty-eight experts in gynecologic radiation oncology contoured three cases, first on a non-contrast CT simulation scan, then with registered diagnostic scans. The cases included (1) FIGO IIIC1 with a bulky tumor and vaginal metastasis, (2) FIGO IIB with calcified uterine fibromas, and (3) FIGO IIIC2 with large lymph nodes. The contours on all six datasets (three CT simulations without diagnostic images and three with registered images) were analyzed for consistency of delineation using an expectation-maximization algorithm for simultaneous truth and performance level estimation (STAPLE) with kappa statistics as a measure of agreement. The contours were reviewed, discussed, and edited in a group meeting prior to finalizing.

Results: Contours showed considerable agreement between experts in each of the cases with kappa statistics of 0.67-0.72. For each case, diagnostic PET±MRI was associated with an increase in volume. The largest increase was the CTV primary for Case 2 with a 20% increase in volume and 54% increase in STAPLE estimate volume, which may be due to variance in registration priorities. For the third case, 92.9% increased their CTVs based on the addition of the diagnostic PET scan. The main areas of variance were in determining the superior extent of CTV coverage, coverage of the mesorectum, and simulation and planning protocols.

Conclusions: This study shows the value as well as the challenges of using co-registered diagnostic imaging, with an average increase in volumes when incorporating MRI and PET.