Verificação Geométrica dos Erros de Setup em Tratamentos Radioterápicos de Cabeça e Pescoço no Hospital Erasto Gaertner
DOI:
https://doi.org/10.29384/rbfm.2023.v17.19849001705Keywords:
Radiotherapy, Head and neck, Geometric verification, setup error, PTV marginAbstract
Setup errors correspond to a group of systematic and random errors that are inherent to radiotherapy treatment and relative to the difference between the planning and actual treatment position. Verification by imaging techniques allows the orientation and magnitude of the treatment position to be determined in relation to the plane, allowing corrections to be made to ensure that the entire target is within the treated volume. This study evaluated the configuration errors of four linear accelerators systems (which use EPID and CR imaging systems) of the Hospital Erasto Gaertner, located in Curitiba-PR. Displacement data from 75 head and neck patients was collected between December, 2021 and August, 2022. From these shifts, the individual and population errors were calculated and the systematic and random components were derived. Thus, the margin from CTV to PTV was estimated using Van Herk formula. The population mean error found was close to zero, and the CTV-PTV average margin was 0.5 cm, which is in accordance with the literature and margins used in the department. This shows that all sector members are following the established protocols and the accessories used can achieve the desired reproducibility, allowing treatments to be done within the margins adopted by the service.
Downloads
References
Perez CA, Brady LW, Halperin EC, Wazer DE. Principles and Practice of Radiation Oncolog. 2013.
Patrízio, RMQ. Avaliação dos desvios no posicionamento dos tumores de cabeça e pescoço. Porto (PT): Instituto Politécnico do Porto; 2015.
ICRU. Report 50: International Commission on Radiation Units and Measurements ICRU Report 50. Prescribing, recording and reporting photon beam therapy. ICRU. Bethesda. MD. 1993.
ICRU. Report 62: Prescribing, recording and reporting photon beam therapy: (supplement to ICRU report 50). Bethesda. MD. 1999.
McGarry CK, Cosgrove VP, Fleming VA, O'Sullivan JM, Hounsell AR. An analysis of geometric uncertainty calculations for prostate radiotherapy in clinical practice. The British Journal of Radiology. 2009; 140-147.
Van Lin EN, Van der Vight L, Huizenga H, Kaanders JH, Visser AG. Set-up improvement in head and neck radiotherapy using a 3D off-line EPID-based correction protocol and s customized head and neck support. Radiotherapy & Oncology. 2003; 137-48.
Hoskin P, et al. On target: ensuring geometric accuracy in radiotherapy. Londres (GB): The Royal College of Radiologist; 2008.
De Boer HCJ, Heijmen BJM. A protocol for the reduction of systematic patient setup erros with minimal portal imaging workload. Radiotherapy & Oncology. 2001; 1350-1365.
Van Herk M. Different styles of image-guided radiotherapy. In:Seminars in radiation oncology. WB Saunders. 2007; 258-267.
Van Asselen B, Dehnad H, Raaijmakers CP, Lagendijk JJ, Terhaard CH. Implanted gold markers for position verification during irradiation of head-and-neck cancers: a feasibility study. Internatinal Journal of Radiation Oncology Biology Physics. 2004; 1011-1017.
Nadalin W. Reprodutibilidade de posicionamento em radioterapia. Revista Brasileira. 2010; 155-162.
Boer HC, Koste JRS, Creutzberg CL, Visser AG, Levendag PC, Heimen BJ. Eletronic portal image assisted reduction of systematic set-up erros in head and neck irradiation. Radiotherapy & Oncology. 2001; 299-307.
Sharp L, Lewin F, Johansson H, Payne D, Gerhardsson A, Rutqvist LE. Randomized trial on two types of thermoplastic masks for patient immobilization during radiationtherapy for head-and-neck câncer. Internatinal Journal of Radiation Oncology Biology Physics. 2005; 250-6.
Zhang L, et al. Multiple regions-of-interes tanalysis of setup uncertainties for head-and-neck câncer radiotherapy. Internatinal Journal of Radiation Oncology Biology Physics. 2006; 1559-6.
De Boer HCJ, Heijmen BJM. eNAL: na extension of the NAL setup correction protocol for effective use of weekly follow-up measurements. International Journal of Radiation Oncology Biology Physycs. 2007; 1586-1565.
Moura, FC. Análise do erro em radioterapia: Impacto dos protocolos de verificação na variabilidade e margem de tratamento. Lisboa (PT): Instituto Politécnico de Lisboa; 2017.
Van Herk M, et al. The probability of correct target dosage: Dose population histograms for deriving treatment margins in radiotherapy. International Journal of Radiation Oncology Biology Physics. 2000; (47):1121-1135.
GuptaT, et al. Assessment of three-dimensional set-up erros in contional head and neck radiotherapy using electronic portal imaging device. International Journal of Radiation Oncology Biology Physics. 2007; 1-8.
Donato K, Leszczynski K, Fleming K. A comparative evaluation of two head and neck immobilization devices using
electronic portal imaging. The British Journal of Radiology. 2006; 158 -161.
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2023 Amanda Pereira Ikeda
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
The submission of original articles to the Brazilian Journal of Medical Physics implies the transfer, by the authors, of the rights of print and digital publication. Copyright for published articles remains with the author, with journal rights on first publication. Authors may only use the same results in other publications by clearly indicating this journal as the original publisher. As we are an open access journal, free use of articles in educational, scientific, non-commercial applications is allowed, as long as the source is cited.
The Brazilian Journal of Medical Physics is under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).
