1
|
Kazemzadeh A, Abedi I, Amouheidari A, Shirvany A. A radiobiological comparison of hypo-fractionation versus conventional fractionation for breast cancer 3D-conformal radiation therapy. ACTA ACUST UNITED AC 2021; 26:86-92. [PMID: 34046218 DOI: 10.5603/rpor.a2021.0015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 12/22/2020] [Indexed: 11/25/2022]
Abstract
Background The present research was aimed to compare the toxicity and effectiveness of conventional fractionated radiotherapy versus hypo-fractionated radiotherapy in breast cancer utilizing a radiobiological model. Materials and methods Thirty-five left-sided breast cancer patients without involvement of the supraclavicular and axillary lymph nodes (with the nodal stage of N0) that had been treated with conventional or hypo-fractionated were incorporated in this study. A radiobiological model was performed to foretell normal tissue complication probability (NTCP) and tumor control probability (TCP). Results The data represented that TCP values for conventional and hypo-fractionated regimens were 99.16 ± 0.09 and 95.96 ± 0.48, respectively (p = 0.00). Moreover, the NTCP values of the lung for conventional and hypo-fractionated treatment were 0.024 versus 0.13 (p = 0.035), respectively. Also, NTCP values of the heart were equal to zero for both regimens. Conclusion In summary, hypo-fractionated regimens had comparable efficacy to conventional fraction radiation therapy in the case of dosimetry parameters for patients who had left breast cancer. But, utilizing the radiobiological model, conventional fractionated regimens presented better results compared to hypo-fractionated regimens.
Collapse
Affiliation(s)
| | - Iraj Abedi
- Medical Physics Department, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | | |
Collapse
|
2
|
Nakano H, Tanabe S, Yamada T, Utsunomiya S, Takizawa T, Sakai M, Sasamoto R, Sakai H, Nakano T, Saito H, Ohta A, Kaidu M, Ishikawa H. Maximum distance in single-isocenter technique of stereotactic radiosurgery with rotational error using margin-based analysis. Radiol Phys Technol 2021; 14:57-63. [PMID: 33393057 DOI: 10.1007/s12194-020-00602-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 12/11/2022]
Abstract
Through geometrical simulation, we evaluated the effect of rotational error in patient setup on geometrical coverage and calculated the maximum distance between the isocenter and target, where the clinical PTV margin secures geometrical coverage with a single-isocenter technique. We used simulated spherical GTVs with diameters of 1.0 (GTV 1), 1.5 (GTV 2), 2.0 (GTV 3), and 3.0 cm (GTV 4). The location of the target center was set such that the distance between the target and isocenter ranged from 0 to 15 cm. We created geometrical coverage vectors so that each target was entirely covered by 100% of the prescribed dose. The vectors of the target positions were simultaneously rotated within a range of 0°-2.0° around the x-, y-, and z-axes. For each rotational error, the reduction in geometrical coverage of the targets was calculated and compared with that obtained for a rotational error of 0°. The tolerance value of the geometrical coverage reduction was defined as 5% of the GTV. The maximum distance that satisfied the 5% tolerance value for different values of rotational error at a clinical PTV margin of 0.1 cm was calculated. When the rotational errors were 0.5° for a 0.1 cm PTV margin, the maximum distances were as follows: GTV 1: 7.6 cm; GTV 2: 10.9 cm; GTV 3: 14.3 cm; and GTV 4: 21.4 cm. It might be advisable to exclude targets that are > 7.6 cm away from the isocenter with a single-isocenter technique to satisfy the tolerance value for all GTVs.
Collapse
Affiliation(s)
- Hisashi Nakano
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan.
| | - Satoshi Tanabe
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Takumi Yamada
- Section of Radiology, Department of Clinical Support, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Satoru Utsunomiya
- Department of Radiological Technology, Niigata University Graduate School of Health Sciences, 2-746 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Takeshi Takizawa
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan.,Department of Radiation Oncology, Niigata Neurosurgical Hospital, Yamada, Nishi-ku, Niigata, 3057, Japan
| | - Madoka Sakai
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Ryuta Sasamoto
- Department of Radiological Technology, Niigata University Graduate School of Health Sciences, 2-746 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Hironori Sakai
- Section of Radiology, Department of Clinical Support, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Toshimichi Nakano
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Hirotake Saito
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Atsushi Ohta
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Motoki Kaidu
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Hiroyuki Ishikawa
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| |
Collapse
|
3
|
Nakano H, Tanabe S, Utsunomiya S, Yamada T, Sasamoto R, Nakano T, Saito H, Takizawa T, Sakai H, Ohta A, Abe E, Kaidu M, Aoyama H. Effect of setup error in the single-isocenter technique on stereotactic radiosurgery for multiple brain metastases. J Appl Clin Med Phys 2020; 21:155-165. [PMID: 33119953 PMCID: PMC7769381 DOI: 10.1002/acm2.13081] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 08/25/2020] [Accepted: 10/06/2020] [Indexed: 01/22/2023] Open
Abstract
In conventional stereotactic radiosurgery (SRS), treatment of multiple brain metastases using multiple isocenters is time‐consuming resulting in long dose delivery times for patients. A single‐isocenter technique has been developed which enables the simultaneous irradiation of multiple targets at one isocenter. This technique requires accurate positioning of the patient to ensure optimal dose coverage. We evaluated the effect of six degrees of freedom (6DoF) setup errors in patient setups on SRS dose distributions for multiple brain metastases using a single‐isocenter technique. We used simulated spherical gross tumor volumes (GTVs) with diameters ranging from 1.0 to 3.0 cm. The distance from the isocenter to the target's center was varied from 0 to 15 cm. We created dose distributions so that each target was entirely covered by 100% of the prescribed dose. The target's position vectors were rotated from 0°–2.0° and translated from 0–1.0 mm with respect to the three axes in space. The reduction in dose coverage for the targets for each setup error was calculated and compared with zero setup error. The calculated margins for the GTV necessary to satisfy the tolerance values for loss of GTV coverage of 3% to 10% were defined as coverage‐based margins. In addition, the maximum isocenter to target distance for different 6DoF setup errors was calculated to satisfy the tolerance values. The dose coverage reduction and coverage‐based margins increased as the target diameter decreased, and the distance and 6DoF setup error increased. An increase in setup error when a single‐isocenter technique is used may increase the risk of missing the tumor; this risk increases with increasing distance from the isocenter and decreasing tumor size.
Collapse
Affiliation(s)
- Hisashi Nakano
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, Chuo-ku, Niigata, Japan
| | - Satoshi Tanabe
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, Chuo-ku, Niigata, Japan
| | - Satoru Utsunomiya
- Department of Radiological Technology, Niigata University Graduate School of Health Sciences, Chuo-ku, Niigata, Japan
| | - Takumi Yamada
- Section of Radiology, Department of Clinical Support, Niigata University Medical and Dental Hospital, Chuo-ku, Niigata, Japan
| | - Ryuta Sasamoto
- Department of Radiological Technology, Niigata University Graduate School of Health Sciences, Chuo-ku, Niigata, Japan
| | - Toshimichi Nakano
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata, Japan
| | - Hirotake Saito
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, Chuo-ku, Niigata, Japan
| | - Takeshi Takizawa
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata, Japan.,Department of Radiation Oncology, Niigata Neurosurgical Hospital, Nishi-ku, Niigata, Japan
| | - Hironori Sakai
- Section of Radiology, Department of Clinical Support, Niigata University Medical and Dental Hospital, Chuo-ku, Niigata, Japan
| | - Atsushi Ohta
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, Chuo-ku, Niigata, Japan
| | - Eisuke Abe
- Department of Radiology, Nagaoka Chuo General Hospital, Nagaoka, Japan
| | - Motoki Kaidu
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata, Japan
| | - Hidefumi Aoyama
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata, Japan.,Department of Radiation Oncology, Faculty of Medicine, Hokkaido University, Kita-ku, Sapporo, Japan
| |
Collapse
|