PMID- 32467675
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20220414
IS  - 1507-1367 (Print)
IS  - 1507-1367 (Linking)
VI  - 24
IP  - 6
DP  - 2019 Nov-Dec
TI  - Biological dose-enhancement analysis with Monte Carlo simulation for Lipiodol for 
      photon beams.
PG  - 681-687
LID - 10.1016/j.rpor.2019.10.006 [doi]
AB  - BACKGROUND: Previously, the physical dose-enhancement factor (D(phys)EF) 
      enhancement was introduced. However, the dose enhancement considering the 
      biological effectiveness was not shown. PURPOSE: The aim of the current study was 
      to evaluate the biological dose-enhancement factor (D(bio)EF) by the dose rate 
      and to compare the D(phys)EF and the D(bio)EF in Lipiodol for liver Stereotactic 
      Body Radiation Therapy (SBRT). MATERIALS AND METHODS: Flattening-filter-free 
      (FFF) 6-MV (6MVX) and 10MVX beams were delivered by TrueBeam. A virtual 
      inhomogeneity phantom and a liver SBRT patient-treatment plan were used. The 
      D(phys)EF and lineal energy distribution ( y ) distribution was calculated from 
      Monte Carlo simulations. Using a microdosimetric-kinetic (MK) model that is 
      estimated based on the linear-quadratic formula for Lipiodol using human liver 
      hepatocellular cells (HepG2), the biological dose and biological dose enhancement 
      factor (D(bio)EF) were calculated. The dose rate in the simulation was changed 
      from 0.1 to 24 Gy/min. RESULTS: The D(bio)EF (DR:2Gy/min) and D(phys)EF with 
      10MVX FFF beam were 23.2% and 19.1% at maximum and 12.8% and 11.1% on average in 
      the Lipiodol. In the comparison of the D(bio)EF between 0.1-24 Gy/min, the 
      D(bio)EF was 21.2% and 11.1% with 0.1 Gy/min for 6MVX and 10 MVX, respectively. 
      The D(bio)EF was larger than DEF for the 6MVX and 10MVX FFF beams. In clinical 
      cases with the 10MVX FFF beam, the D(bio)EF and D(phys)EF in the Lipiodol region 
      can increase the in-tumor dose by approximately 11% and 10%, respectively, 
      without increasing the dose to normal tissue. CONCLUSIONS: The lower-energy and 
      higher-dose-rate beams were contributed to the biological dose. The Lipiodol 
      caused the enhancement of the physical dose and biological effectiveness. 
      ADVANCES IN KNOWLEDGE: The biological dose enhancement (D(bio)EF) should be 
      considered in the high-density material such as the Lipiodol.
CI  - (c) 2019 Greater Poland Cancer Centre. Published by Elsevier B.V. All rights 
      reserved.
FAU - Kawahara, Daisuke
AU  - Kawahara D
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Japan.
FAU - Ozawa, Shuichi
AU  - Ozawa S
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Japan.
AD  - Hiroshima High-Precision Radiotherapy Cancer Center, Japan.
FAU - Nakano, Hisashi
AU  - Nakano H
AD  - Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 
      Japan.
FAU - Kubo, Katsumaro
AU  - Kubo K
AD  - Department of Radiation Oncology, Hiroshima Prefectural Hospital, Japan.
FAU - Shiinoki, Takehiro
AU  - Shiinoki T
AD  - Department of Radiation Oncology, Graduate School of Medicine, Yamaguchi 
      University, Japan.
FAU - Kimura, Tomoki
AU  - Kimura T
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Japan.
FAU - Nagata, Yasushi
AU  - Nagata Y
AD  - Department of Radiation Oncology, Institute of Biomedical & Health Sciences, 
      Hiroshima University, Japan.
AD  - Hiroshima High-Precision Radiotherapy Cancer Center, Japan.
LA  - eng
PT  - Journal Article
DEP - 20191108
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 - PMC7239937
OTO - NOTNLM
OT  - Lipiodol
OT  - MK model
OT  - Monte Carlo calculation
OT  - Radiobiological dose enhancement
EDAT- 2020/05/30 06:00
MHDA- 2020/05/30 06:01
CRDT- 2020/05/30 06:00
PHST- 2018/12/05 00:00 [received]
PHST- 2019/08/01 00:00 [revised]
PHST- 2019/10/07 00:00 [accepted]
PHST- 2020/05/30 06:00 [entrez]
PHST- 2020/05/30 06:00 [pubmed]
PHST- 2020/05/30 06:01 [medline]
AID - S1507-1367(19)30090-2 [pii]
AID - 10.1016/j.rpor.2019.10.006 [doi]
PST - ppublish
SO  - Rep Pract Oncol Radiother. 2019 Nov-Dec;24(6):681-687. doi: 
      10.1016/j.rpor.2019.10.006. Epub 2019 Nov 8.