PMID- 36523809
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20221221
IS  - 1507-1367 (Print)
IS  - 2083-4640 (Electronic)
IS  - 1507-1367 (Linking)
VI  - 27
IP  - 5
DP  - 2022
TI  - Improved biological dosimetric margin model for different PTV margins with 
      stereotactic body radiation therapy in homogeneous and nonhomogeneous tumor 
      regions.
PG  - 768-777
LID - 10.5603/RPOR.a2022.0086 [doi]
AB  - BACKGROUND: The purpose of this study was to improve the biological dosimetric 
      margin (BDM) corresponding to different planning target volume (PTV) margins in 
      homogeneous and nonhomogeneous tumor regions using an improved biological 
      conversion factor (BCF) model for stereotactic body radiation therapy (SBRT). 
      MATERIALS AND METHODS: The PTV margin was 5-20 mm from the clinical target 
      volume. The biologically equivalent dose (BED) was calculated using the 
      linear-quadratic model. The biological parameters were alpha/beta = 10 Gy, and the dose 
      per fraction (DPF) was d = 3-20 Gy/fr. The isocenter was offset at intervals of 1 
      mm; 95% of the clinical target volume covered more than 90% of the prescribed 
      physical dose, and BED was defined as biological and physical DMs. The BCF 
      formula was defined as a function of the DPF. RESULTS: The difference in the BCF 
      caused by the DPF was within 0.05 for the homogeneous and nonhomogeneous 
      phantoms. In the virtual nonhomogeneous phantom, the data with a PTV margin of 
      10-20 mm were not significantly different; thus, these were combined to fit the 
      BCF. In the virtual homogeneous phantom, the BCF was fitted to each PTV margin. 
      CONCLUSIONS: The current study improved a scheme to estimate the BDM considering 
      the size of the PTV margin and homogeneous and nonhomogeneous regions. This 
      technique is expected to enable BED-based treatment planning using treatment 
      systems based on physical doses for SBRT.
CI  - (c) 2022 Greater Poland Cancer Centre.
FAU - Kawahara, Daisuke
AU  - Kawahara D
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Hiroshima, Japan.
FAU - Saito, Akito
AU  - Saito A
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Hiroshima, Japan.
FAU - Nagata, Yasushi
AU  - Nagata Y
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Hiroshima, Japan.
AD  - Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan.
LA  - eng
PT  - Journal Article
DEP - 20221031
PL  - Poland
TA  - Rep Pract Oncol Radiother
JT  - Reports of practical oncology and radiotherapy : journal of Greatpoland Cancer 
      Center in Poznan and Polish Society of Radiation Oncology
JID - 100885761
PMC - PMC9746637
OTO - NOTNLM
OT  - SBRT
OT  - biological equivalent dose
OT  - dosimetric margin
OT  - photon therapy
COIS- Conflict of interest None declared.
EDAT- 2022/12/17 06:00
MHDA- 2022/12/17 06:01
PMCR- 2022/10/31
CRDT- 2022/12/16 02:27
PHST- 2022/05/31 00:00 [received]
PHST- 2022/07/05 00:00 [accepted]
PHST- 2022/12/16 02:27 [entrez]
PHST- 2022/12/17 06:00 [pubmed]
PHST- 2022/12/17 06:01 [medline]
PHST- 2022/10/31 00:00 [pmc-release]
AID - rpor-27-5-768 [pii]
AID - 10.5603/RPOR.a2022.0086 [doi]
PST - epublish
SO  - Rep Pract Oncol Radiother. 2022 Oct 31;27(5):768-777. doi: 
      10.5603/RPOR.a2022.0086. eCollection 2022.