PMID- 35106384
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20220430
IS  - 2405-6316 (Electronic)
IS  - 2405-6316 (Linking)
VI  - 21
DP  - 2022 Jan
TI  - Reduction of systematic dosimetric uncertainties in volumetric modulated arc 
      therapy triggered by patient-specific quality assurance.
PG  - 6-10
LID - 10.1016/j.phro.2022.01.001 [doi]
AB  - BACKGROUND AND PURPOSE: Dosimetric patient-Specific Quality Assurance (PSQA) data 
      contain in addition to cases with alerts, many cases without alerts. The aim of 
      this study was to present a procedure to investigate long-term trend analysis of 
      the complete set of PSQA data for the presence of site-specific deviations to 
      reduce underlying systematic dose uncertainties. MATERIALS AND METHODS: The 
      procedure started by analysing a large set of prostate Volumetric Modulated Arc 
      Therapy (VMAT) PSQA data obtained by comparing 3D electronic portal image device 
      (EPID)_based in vivo dosimetry measurements with dose values predicted by the 
      Treatment Planning System (TPS). If systematic deviations were present, several 
      actions were required. These included confirmation of these deviations with an 
      independent dose verification system for which a 2D detector array in a phantom 
      was used, and analysing calculated with measured PSQA data, or delivery machine 
      characteristics. Further analysis revealed that the under-dosage correlated with 
      plan complexity and coincided with changes in clinically applied planning 
      techniques. RESULTS: Prostate VMAT PSQA data showed an under-dosage gradual 
      increasing to about 2% in 3 years, which was confirmed by the measurements with 
      the 2D detector array in a phantom. The implementation of new beam fits in the 
      TPS led to a reduction of the observed deviations. CONCLUSION: Long-term analysis 
      of site-specific PSQA data is a useful method to monitor incremental changes in a 
      radiotherapy department due to various changes in the treatment planning and 
      delivery of prostate VMAT, and may lead to a reduction of systematic dose 
      uncertainties in complex treatments.
CI  - (c) 2022 The Authors.
FAU - Mans, Anton
AU  - Mans A
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
FAU - Rozendaal, Roel
AU  - Rozendaal R
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
FAU - Janssen, Tomas
AU  - Janssen T
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
FAU - Damen, Eugene
AU  - Damen E
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
FAU - Kaas, Jochem
AU  - Kaas J
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
FAU - van Mourik, Anke
AU  - van Mourik A
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
FAU - Mijnheer, Ben
AU  - Mijnheer B
AD  - Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, 
      The Netherlands.
LA  - eng
PT  - Journal Article
DEP - 20220120
PL  - Netherlands
TA  - Phys Imaging Radiat Oncol
JT  - Physics and imaging in radiation oncology
JID - 101704276
PMC - PMC8789528
OTO - NOTNLM
OT  - 3D EPID dosimetry
OT  - Detector array
OT  - Patient-specific QA
OT  - Plan complexity
OT  - Time-trends
OT  - VMAT
COIS- The authors declare that they have no known competing financial interests or 
      personal relationships that could have appeared to influence the work reported in 
      this paper.
EDAT- 2022/02/03 06:00
MHDA- 2022/02/03 06:01
PMCR- 2022/01/20
CRDT- 2022/02/02 05:35
PHST- 2021/02/22 00:00 [received]
PHST- 2021/12/24 00:00 [revised]
PHST- 2022/01/07 00:00 [accepted]
PHST- 2022/02/02 05:35 [entrez]
PHST- 2022/02/03 06:00 [pubmed]
PHST- 2022/02/03 06:01 [medline]
PHST- 2022/01/20 00:00 [pmc-release]
AID - S2405-6316(22)00001-X [pii]
AID - 10.1016/j.phro.2022.01.001 [doi]
PST - epublish
SO  - Phys Imaging Radiat Oncol. 2022 Jan 20;21:6-10. doi: 10.1016/j.phro.2022.01.001. 
      eCollection 2022 Jan.