Back to Search
Start Over
Trend analysis of the dosimetric impact of anatomical changes during proton therapy for maxillary sinus carcinoma
- Source :
- Journal of Applied Clinical Medical Physics
- Publication Year :
- 2021
- Publisher :
- Wiley, 2021.
-
Abstract
- Purpose Anatomical changes, such as shrinkage and aeration, can affect dose distribution in proton therapy (PT) for maxillary sinus carcinoma (MSC). These changes can affect the dose to the target and organs at risk (OARs); however, when these changes occur during PT is unclear. This study aimed to investigate the dosimetric impact of anatomical changes during PT. Materials and Methods Fifteen patients with MSC were enrolled in this study. Initial PT plans were generated based on initial computed tomography (CT) images. Several repeat CT images were obtained to confirm anatomical changes during PT. Evaluation PT plans were generated by copying initial PT plans to repeat CT images. The dose differences of the target and OARs were evaluated by comparing both the plans. Results At 3–4 weeks after the initiation of PT, the target volume reduced by approximately 10% as compared with the initial volume. Consequently, the target volumes gradually varied until the end of treatment. The value of V95 (volume that received 95% of the prescription dose) in the clinical target volume of the evaluation PT plan was similar to that of the initial PT plan. However, the dose to OARs, such as the contralateral optic nerve, contralateral eyeball, brainstem, and optic chiasm, increased significantly from the middle to the later phases of the treatment course. In contrast, there was a slight dose difference in the ipsilateral optic apparatus. Conclusion The trend analysis in this study showed that anatomical changes appeared 3–4 weeks after the start of PT, and the dose to the OARs tended to increase. Therefore, it is recommended to check the status of tumor 3–4 weeks after the start of treatment to avoid the deterioration of dose distribution due to these changes.
- Subjects :
- Planning target volume
Optic chiasm
Computed tomography
Dose distribution
anatomical change
Disease course
Proton Therapy
medicine
Radiation Oncology Physics
maxillary sinus carcinoma
Humans
Radiology, Nuclear Medicine and imaging
Instrumentation
Proton therapy
Radiation
medicine.diagnostic_test
business.industry
Radiotherapy Planning, Computer-Assisted
Carcinoma
Radiotherapy Dosage
Maxillary Sinus
Maxillary Sinus Carcinoma
medicine.anatomical_structure
adaptive radiotherapy
Optic nerve
sense organs
business
Nuclear medicine
Subjects
Details
- ISSN :
- 15269914
- Volume :
- 22
- Database :
- OpenAIRE
- Journal :
- Journal of Applied Clinical Medical Physics
- Accession number :
- edsair.doi.dedup.....6cbd2812137f085309cb3f1141720910
- Full Text :
- https://doi.org/10.1002/acm2.13391