A dosimetry study of post-mastectomy radiation therapy with AeroForm tissue expander
| Autor: | Hsiang Chi Kuo, Beryl McCormick, Simon N. Powell, Guang Li, Oren Cahlon, Li Cheng Kuo, Linda X. Hong, Seng Boh Lim |
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| Rok vydání: | 2020 |
| Předmět: |
Thorax
Materials science Film Dosimetry medicine.medical_treatment Breast Neoplasms Imaging phantom 030218 nuclear medicine & medical imaging 03 medical and health sciences breast cancer 0302 clinical medicine Post mastectomy medicine Radiation Oncology Physics post‐mastectomy radiation therapy Dosimetry Humans Radiology Nuclear Medicine and imaging Irradiation Radiometry Instrumentation Mastectomy Tissue expander Radiation Dosimeter business.industry Phantoms Imaging Radiotherapy Planning Computer-Assisted Tissue Expansion Devices Radiotherapy Dosage OLSD dosimetry Radiation therapy 030220 oncology & carcinogenesis AeroForm tissue expander Female Nuclear medicine business Algorithms |
| Zdroj: | Journal of Applied Clinical Medical Physics |
| ISSN: | 1526-9914 |
| Popis: | Purpose To evaluate the dosimetric effects of the AeroFormTM (AirXanpders®, Palo Alto, CA) tissue expander in‐situ for breast cancer patients receiving post‐mastectomy radiation therapy. Methods and Materials A film phantom (P1) was constructed by placing the metallic canister of the AeroForm on a solid water phantom with EBT3 films at five depths ranging from 2.6 mm to 66.2 mm. A breast phantom (P2), a three‐dimensional printed tissue‐equivalent breast with fully expanded AeroForm in‐situ, was placed on a thorax phantom. A total of 21 optical luminescent dosimeters (OLSDs) were placed on the anterior skin–gas interface and the posterior chest wall–metal interface of the AeroForm. Both phantoms were imaged with a 16‐bit computed tomography scanner with orthopedic metal artifact reduction. P1 was irradiated with an open field utilizing 6 MV and 15 MV photon beams at 0°, 90°, and 270°. P2 was irradiated using a volumetric modulated arc therapy plan with a 6 MV photon beam and a tangential plan with a 15 MV photon beam. All doses were calculated using Eclipse (Varian, Palo Alto, CA) with AAA and AcurosXB (AXB) algorithms. Results The average dose differences between film measurements and AXB in the region adjacent to the canister in P1 were within 3.1% for 15 MV and 0.9% for 6 MV. Local dose differences over 10% were also observed. In the chest wall region of P2, the median dose of OLSDs in percentage of prescription dose were 108.4% (range 95.4%–113.0%) for the 15MV tangential plan and 110.4% (range 99.1%–113.8%) for the 6MV volumetric modulated arc therapy plan. In the skin–gas interface, the median dose of the OLSDs were 102.3% (range 92.7%–107.7%) for the 15 MV plan and 108.2% (range 97.8–113.5%) for the 6 MV plan. Measured doses were, in general, higher than calculated doses with AXB calculations. The AAA dose algorithms produced results with slightly larger discrepancies between measurements compared with AXB. Conclusions The AeroForm creates significant dose uncertainties in the chest wall–metal interface. The AcurosXB dose calculation algorithm is recommended for more accurate calculations. If possible, post‐mastectomy radiation therapy should be delivered after the permanent implant is in place. |
| Databáze: | OpenAIRE |
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