Mean Dose Constraint in Optimization Shells of a Lung SBRT Plan Helps further Reduce Normal Lung Dose
-
Tran Duc Hung
,
Nguyen Thi Van Anh
,
Le Manh Duc
,
Quach Ngoc Mai
,
Trinh Thi Mai
,
Tran Kim Thoa
,
Bui Quang Bieu
,
Hoang Huu Thai
,
Pham Hong Lam
,
Nguyen The Thuong
,
Quang Trung PHAM
Abstract
Purpose: This study aims to explore the effect of mean dose constraint in optimization shells on the reduction of normal lung dose in lung Stereotactic Body Radiation Therapy (SBRT) plans.
Materials and Methods: This study investigated 28 VMAT-based lung SBRT plans optimized with three artificial shells, which were re-generated with the same setup and an additional mean dose constraint besides the maximum dose limit. Dosimetric measurements of target volume and Organs At Risk (OARs) were compared between the original plans and re-generated ones using the Wilcoxon signed-rank test at 5% level significance (two-tailed).
Results: Replanning resulted in slight improvements in some parameters, such as R50% and the Gradient Measure (GM), which were reduced by 1.3% and 1.0%, respectively, with p < 0.05. However, there were slight increases in other parameters, such as D2cm and the maximum target dose, though these increases were not statistically significant. The Conformity Index (CI) remained nearly identical, with a mean value of 0.99 ± 0.03 for both original and re-optimized plans. Similarly, the V105% values were consistent, with mean values of 0.02 ± 0.13% in both groups. The parameters for dose deposited in normal lung tissue showed statistically significant reductions ranging from 1.0% to 1.7%. In addition, the mean dose to the spinal cord, esophagus, and skin was slightly reduced, but the mean dose to the heart showed a slight increase.
Conclusion: The study found that adding mean dose constraints to optimization shells in lung SBRT plans can reduce normal lung dose while maintaining dose conformity to the target. However, there may be slight changes in some OARs such as the spinal cord, esophagus, and skin. These changes were not statistically significant.
1- David Hoffman, Irena Dragojević, Jeremy Hoisak, David Hoopes, and Ryan Manger, "Lung Stereotactic Body Radiation Therapy (SBRT) dose gradient and PTV volume: a retrospective multi-center analysis." (in eng), Radiation oncology (London, England), Vol. 14 (No. 1), pp. 162-62, (2019).
2- M. Uematsu et al., "Computed tomography-guided frameless stereotactic radiotherapy for stage I non-small cell lung cancer: a 5-year experience." (in eng), International journal of radiation oncology, biology, physics, Vol. 51 (No. 3), pp. 666-70, (2001).
3- Marta Adamczyk, Marta Kruszyna-Mochalska, Anna Rucińska, and Tomasz Piotrowski, "Software simulation of tumour motion dose effects during flattened and unflattened ITV-based VMAT lung SBRT." Reports of Practical Oncology & Radiotherapy, Vol. 25 (No. 4), pp. 684-91, (2020).
4- Serena Badellino et al., "No differences in radiological changes after 3D conformal vs VMAT-based stereotactic radiotherapy for early stage non-small cell lung cancer." (in eng), The British journal of radiology, Vol. 90 (No. 1078), pp. 20170143-43, (2017).
5- C. Herbert et al., "Stereotactic body radiotherapy: volumetric modulated arc therapy versus 3D non-coplanar conformal radiotherapy for the treatment of early stage lung cancer." (in eng), Technology in Cancer Research & Treatment, Vol. 12 (No. 6), pp. 511-16, (2013).
6- Andrea Holt, Corine van Vliet-Vroegindeweij, Anton Mans, José S. Belderbos, and Eugène M. F. Damen, "Volumetric-modulated arc therapy for stereotactic body radiotherapy of lung tumors: a comparison with intensity-modulated radiotherapy techniques." (in eng), International journal of radiation oncology, biology, physics, Vol. 81 (No. 5), pp. 1560-67, (2011).
7- Chin Loon Ong, Wilko F. A. R. Verbakel, Johan P. Cuijpers, Ben J. Slotman, Frank J. Lagerwaard, and Suresh Senan, "Stereotactic radiotherapy for peripheral lung tumors: a comparison of volumetric modulated arc therapy with 3 other delivery techniques." (in eng), Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, Vol. 97 (No. 3), pp. 437-42, (2010).
8- Masahide Saito et al., "Evaluation of the target dose coverage of stereotactic body radiotherapy for lung cancer using helical tomotherapy: A dynamic phantom study." Reports of Practical Oncology & Radiotherapy, Vol. 25 (No. 2), pp. 200-05, (2020).
9- Liza I. Ndrayani, Choirul A. Nam, Heri S. Utanto, and Rinarto S. Ubroto, "Normal tissue objective ( NTO ) tool in Eclipse treatment planning system for dose distribution optimization." Polish Journal of Medical Physics And Engineering, Vol. 28 (No. June), pp. 99-106, (2022).
10- Daniel Buergy et al., "Fully automated treatment planning of spinal metastases - A comparison to manual planning of Volumetric Modulated Arc Therapy for conventionally fractionated irradiation." (in eng), Radiation oncology (London, England), Vol. 12 (No. 1), pp. 33-33, (2017).
11- Yangsen Cao et al., "Optimization of dose distributions of target volumes and organs at risk during stereotactic body radiation therapy for pancreatic cancer with dose-limiting auto-shells." (in eng), Radiation oncology (London, England), Vol. 13 (No. 1), pp. 11-11, (2018).
12- Dharmin Desai et al., "Cleaning the dose falloff in lung SBRT plan." (in eng), Journal of applied clinical medical physics, Vol. 22 (No. 1), pp. 100-08, (2021).
13- Yanhua Duan et al., "On the optimal number of dose-limiting shells in the SBRT auto-planning design for peripheral lung cancer." (in eng), Journal of applied clinical medical physics, Vol. 21 (No. 9), pp. 134-42, (2020).
14- Abdul Wahab M. Sharfo, Peter W. J. Voet, Sebastiaan Breedveld, Jan Willem M. Mens, Mischa S. Hoogeman, and Ben J. M. Heijmen, "Comparison of VMAT and IMRT strategies for cervical cancer patients using automated planning." (in eng), Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, Vol. 114 (No. 3), pp. 395-401, (2015).
15- Osamu Tanaka et al., "Stereotactic body radiation therapy to the spine: contouring the cauda equina instead of the spinal cord is more practical as the organ at risk." Reports of Practical Oncology and Radiotherapy, Vol. 28 (No. 3), pp. 407-15, (2023).
16- Peter W. J. Voet, Maarten L. P. Dirkx, Sebastiaan Breedveld, and Ben J. M. Heijmen, "Automated generation of IMRT treatment plans for prostate cancer patients with metal hip prostheses: comparison of different planning strategies." (in eng), Medical physics, Vol. 40 (No. 7), pp. 71704-04, (2013).
17- Kirk Luca et al., "A lung SBRT treatment planning technique to focus high dose on gross disease." Medical Dosimetry, 2024/09/10/ (2024).
18- X. Qian et al., "The optimal stereotactic body radiotherapy dose with immunotherapy for pulmonary oligometastases: a retrospective cohort study." (in eng), J Thorac Dis, Vol. 16 (No. 10), pp. 7072-85, Oct 31 (2024).
19- Andrea Bezjak et al., "Safety and Efficacy of a Five-Fraction Stereotactic Body Radiotherapy Schedule for Centrally Located Non-Small-Cell Lung Cancer: NRG Oncology/RTOG 0813 Trial." (in eng), Journal of clinical oncology : official journal of the American Society of Clinical Oncology, Vol. 37 (No. 15), pp. 1316-25, (2019).
20- Gregory M. M. Videtic et al., "A Randomized Phase 2 Study Comparing 2 Stereotactic Body Radiation Therapy Schedules for Medically Inoperable Patients With Stage I Peripheral Non-Small Cell Lung Cancer: NRG Oncology RTOG 0915 (NCCTG N0927)." (in eng), International journal of radiation oncology, biology, physics, Vol. 93 (No. 4), pp. 757-64, (2015).
21- Ganesh Narayanasamy, Dharmin Desai, Sanjay Maraboyina, Jose Penagaricano, Robert Zwicker, and Ellis Lee Johnson, "A Dose Falloff Gradient Study in RapidArc Planning of Lung Stereotactic Body Radiation Therapy." (in eng), Journal of medical physics, Vol. 43 (No. 3), pp. 147-54, (2018).
22- Houda Bahig et al., "Excellent Cancer Outcomes Following Patient-adapted Robotic Lung SBRT But a Case for Caution in Idiopathic Pulmonary Fibrosis." (in eng), Technology in Cancer Research & Treatment, Vol. 14 (No. 6), pp. 667-76, (2015).
23- Ryan Baker et al., "Clinical and dosimetric predictors of radiation pneumonitis in a large series of patients treated with stereotactic body radiation therapy to the lung." (in eng), International journal of radiation oncology, biology, physics, Vol. 85 (No. 1), pp. 190-95, (2013).
24- Guillaume Dupic et al., "Significant Correlation Between Overall Survival and Mean Lung Dose in Lung Stereotactic Body Radiation Therapy (SBRT)." (in eng), Frontiers in oncology, Vol. 10pp. 1577-77, (2020).
25- Eileen M. Harder, Henry S. Park, Zhe Chen, and Roy H. Decker, "Pulmonary dose-volume predictors of radiation pneumonitis following stereotactic body radiation therapy." Practical Radiation Oncology, Vol. 6 (No. 6), pp. e353-e59, (2016).
26- Jing Zhao et al., "Simple Factors Associated With Radiation-Induced Lung Toxicity After Stereotactic Body Radiation Therapy of the Thorax: A Pooled Analysis of 88 Studies." (in eng), International journal of radiation oncology, biology, physics, Vol. 95 (No. 5), pp. 1357-66, (2016).
27- Dharmin D. Desai, Ivan L. Cordrey, and E. L. Johnson, "A physically meaningful relationship between R50% and PTV surface area in lung SBRT." (in eng), Journal of applied clinical medical physics, Vol. 21 (No. 9), pp. 47-56, (2020).
28- Dharmin D. Desai, E. L. Johnson, and Ivan L. Cordrey, "An analytical expression for R50% dependent on PTV surface area and volume: a lung SBRT comparison." (in eng), Journal of applied clinical medical physics, Vol. 21 (No. 11), pp. 278-82, (2020).
29- B. T. Huang, Z. Lin, P. X. Lin, J. Y. Lu, and C. Z. Chen, "Monitor unit optimization in stereotactic body radiotherapy for small peripheral non-small cell lung cancer patients." (in eng), Sci Rep, Vol. 5p. 18453, Dec 18 (2015).
2- M. Uematsu et al., "Computed tomography-guided frameless stereotactic radiotherapy for stage I non-small cell lung cancer: a 5-year experience." (in eng), International journal of radiation oncology, biology, physics, Vol. 51 (No. 3), pp. 666-70, (2001).
3- Marta Adamczyk, Marta Kruszyna-Mochalska, Anna Rucińska, and Tomasz Piotrowski, "Software simulation of tumour motion dose effects during flattened and unflattened ITV-based VMAT lung SBRT." Reports of Practical Oncology & Radiotherapy, Vol. 25 (No. 4), pp. 684-91, (2020).
4- Serena Badellino et al., "No differences in radiological changes after 3D conformal vs VMAT-based stereotactic radiotherapy for early stage non-small cell lung cancer." (in eng), The British journal of radiology, Vol. 90 (No. 1078), pp. 20170143-43, (2017).
5- C. Herbert et al., "Stereotactic body radiotherapy: volumetric modulated arc therapy versus 3D non-coplanar conformal radiotherapy for the treatment of early stage lung cancer." (in eng), Technology in Cancer Research & Treatment, Vol. 12 (No. 6), pp. 511-16, (2013).
6- Andrea Holt, Corine van Vliet-Vroegindeweij, Anton Mans, José S. Belderbos, and Eugène M. F. Damen, "Volumetric-modulated arc therapy for stereotactic body radiotherapy of lung tumors: a comparison with intensity-modulated radiotherapy techniques." (in eng), International journal of radiation oncology, biology, physics, Vol. 81 (No. 5), pp. 1560-67, (2011).
7- Chin Loon Ong, Wilko F. A. R. Verbakel, Johan P. Cuijpers, Ben J. Slotman, Frank J. Lagerwaard, and Suresh Senan, "Stereotactic radiotherapy for peripheral lung tumors: a comparison of volumetric modulated arc therapy with 3 other delivery techniques." (in eng), Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, Vol. 97 (No. 3), pp. 437-42, (2010).
8- Masahide Saito et al., "Evaluation of the target dose coverage of stereotactic body radiotherapy for lung cancer using helical tomotherapy: A dynamic phantom study." Reports of Practical Oncology & Radiotherapy, Vol. 25 (No. 2), pp. 200-05, (2020).
9- Liza I. Ndrayani, Choirul A. Nam, Heri S. Utanto, and Rinarto S. Ubroto, "Normal tissue objective ( NTO ) tool in Eclipse treatment planning system for dose distribution optimization." Polish Journal of Medical Physics And Engineering, Vol. 28 (No. June), pp. 99-106, (2022).
10- Daniel Buergy et al., "Fully automated treatment planning of spinal metastases - A comparison to manual planning of Volumetric Modulated Arc Therapy for conventionally fractionated irradiation." (in eng), Radiation oncology (London, England), Vol. 12 (No. 1), pp. 33-33, (2017).
11- Yangsen Cao et al., "Optimization of dose distributions of target volumes and organs at risk during stereotactic body radiation therapy for pancreatic cancer with dose-limiting auto-shells." (in eng), Radiation oncology (London, England), Vol. 13 (No. 1), pp. 11-11, (2018).
12- Dharmin Desai et al., "Cleaning the dose falloff in lung SBRT plan." (in eng), Journal of applied clinical medical physics, Vol. 22 (No. 1), pp. 100-08, (2021).
13- Yanhua Duan et al., "On the optimal number of dose-limiting shells in the SBRT auto-planning design for peripheral lung cancer." (in eng), Journal of applied clinical medical physics, Vol. 21 (No. 9), pp. 134-42, (2020).
14- Abdul Wahab M. Sharfo, Peter W. J. Voet, Sebastiaan Breedveld, Jan Willem M. Mens, Mischa S. Hoogeman, and Ben J. M. Heijmen, "Comparison of VMAT and IMRT strategies for cervical cancer patients using automated planning." (in eng), Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, Vol. 114 (No. 3), pp. 395-401, (2015).
15- Osamu Tanaka et al., "Stereotactic body radiation therapy to the spine: contouring the cauda equina instead of the spinal cord is more practical as the organ at risk." Reports of Practical Oncology and Radiotherapy, Vol. 28 (No. 3), pp. 407-15, (2023).
16- Peter W. J. Voet, Maarten L. P. Dirkx, Sebastiaan Breedveld, and Ben J. M. Heijmen, "Automated generation of IMRT treatment plans for prostate cancer patients with metal hip prostheses: comparison of different planning strategies." (in eng), Medical physics, Vol. 40 (No. 7), pp. 71704-04, (2013).
17- Kirk Luca et al., "A lung SBRT treatment planning technique to focus high dose on gross disease." Medical Dosimetry, 2024/09/10/ (2024).
18- X. Qian et al., "The optimal stereotactic body radiotherapy dose with immunotherapy for pulmonary oligometastases: a retrospective cohort study." (in eng), J Thorac Dis, Vol. 16 (No. 10), pp. 7072-85, Oct 31 (2024).
19- Andrea Bezjak et al., "Safety and Efficacy of a Five-Fraction Stereotactic Body Radiotherapy Schedule for Centrally Located Non-Small-Cell Lung Cancer: NRG Oncology/RTOG 0813 Trial." (in eng), Journal of clinical oncology : official journal of the American Society of Clinical Oncology, Vol. 37 (No. 15), pp. 1316-25, (2019).
20- Gregory M. M. Videtic et al., "A Randomized Phase 2 Study Comparing 2 Stereotactic Body Radiation Therapy Schedules for Medically Inoperable Patients With Stage I Peripheral Non-Small Cell Lung Cancer: NRG Oncology RTOG 0915 (NCCTG N0927)." (in eng), International journal of radiation oncology, biology, physics, Vol. 93 (No. 4), pp. 757-64, (2015).
21- Ganesh Narayanasamy, Dharmin Desai, Sanjay Maraboyina, Jose Penagaricano, Robert Zwicker, and Ellis Lee Johnson, "A Dose Falloff Gradient Study in RapidArc Planning of Lung Stereotactic Body Radiation Therapy." (in eng), Journal of medical physics, Vol. 43 (No. 3), pp. 147-54, (2018).
22- Houda Bahig et al., "Excellent Cancer Outcomes Following Patient-adapted Robotic Lung SBRT But a Case for Caution in Idiopathic Pulmonary Fibrosis." (in eng), Technology in Cancer Research & Treatment, Vol. 14 (No. 6), pp. 667-76, (2015).
23- Ryan Baker et al., "Clinical and dosimetric predictors of radiation pneumonitis in a large series of patients treated with stereotactic body radiation therapy to the lung." (in eng), International journal of radiation oncology, biology, physics, Vol. 85 (No. 1), pp. 190-95, (2013).
24- Guillaume Dupic et al., "Significant Correlation Between Overall Survival and Mean Lung Dose in Lung Stereotactic Body Radiation Therapy (SBRT)." (in eng), Frontiers in oncology, Vol. 10pp. 1577-77, (2020).
25- Eileen M. Harder, Henry S. Park, Zhe Chen, and Roy H. Decker, "Pulmonary dose-volume predictors of radiation pneumonitis following stereotactic body radiation therapy." Practical Radiation Oncology, Vol. 6 (No. 6), pp. e353-e59, (2016).
26- Jing Zhao et al., "Simple Factors Associated With Radiation-Induced Lung Toxicity After Stereotactic Body Radiation Therapy of the Thorax: A Pooled Analysis of 88 Studies." (in eng), International journal of radiation oncology, biology, physics, Vol. 95 (No. 5), pp. 1357-66, (2016).
27- Dharmin D. Desai, Ivan L. Cordrey, and E. L. Johnson, "A physically meaningful relationship between R50% and PTV surface area in lung SBRT." (in eng), Journal of applied clinical medical physics, Vol. 21 (No. 9), pp. 47-56, (2020).
28- Dharmin D. Desai, E. L. Johnson, and Ivan L. Cordrey, "An analytical expression for R50% dependent on PTV surface area and volume: a lung SBRT comparison." (in eng), Journal of applied clinical medical physics, Vol. 21 (No. 11), pp. 278-82, (2020).
29- B. T. Huang, Z. Lin, P. X. Lin, J. Y. Lu, and C. Z. Chen, "Monitor unit optimization in stereotactic body radiotherapy for small peripheral non-small cell lung cancer patients." (in eng), Sci Rep, Vol. 5p. 18453, Dec 18 (2015).
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| Issue | Vol 13 No 3 (2026) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/fbt.v13i3.22746 | |
| Keywords | ||
| Lung Stereotactic Body Radiation Therapy Dose Falloff Dose Gradient Normal Lung Dose Optimization Shells Mean Dose Constraints | ||
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How to Cite
1.
Hung T, Van Anh N, Duc L, Mai Q, Mai T, Thoa T, Bieu B, Thai H, Lam P, Thuong N, PHAM QT. Mean Dose Constraint in Optimization Shells of a Lung SBRT Plan Helps further Reduce Normal Lung Dose. Frontiers Biomed Technol. 2026;13(3):744-754.
