PMID- 23531301
OWN - NLM
STAT- MEDLINE
DCOM- 20131231
LR  - 20211021
IS  - 1748-717X (Electronic)
IS  - 1748-717X (Linking)
VI  - 8
DP  - 2013 Mar 25
TI  - Evaluation and comparison of New 4DCT based strategies for proton treatment 
      planning for lung tumors.
PG  - 73
LID - 10.1186/1748-717X-8-73 [doi]
AB  - PURPOSE: To evaluate different strategies for proton lung treatment planning 
      based on four-dimensional CT (4DCT) scans. METHODS AND MATERIALS: Twelve cases, 
      involving only gross tumor volumes (GTV), were evaluated. Single image sets of 
      (1) maximum intensity projection (MIP3) of end inhale (EI), middle exhale (ME) 
      and end exhale (EE) images; (2) average intensity projection (AVG) of all phase 
      images; and (3) EE images from 4DCT scans were selected as primary images for 
      proton treatment planning. Internal target volumes (ITVs) outlined by a clinician 
      were imported into MIP3, AVG, and EE images as planning targets. Initially, 
      treatment uncertainties were not included in planning. Each plan was imported 
      into phase images of 4DCT scans. Relative volumes of GTVs covered by 95% of 
      prescribed dose and mean ipsilateral lung dose of a phase image obtained by 
      averaging the dose in inspiration and expiration phases were used to evaluate the 
      quality of a plan for a particular case. For comparing different planning 
      strategies, the mean of the averaged relative volumes of GTVs covered by 95% of 
      prescribed dose and its standard deviation for each planning strategy for all 
      cases were used. Then, treatment uncertainties were included in planning. Each 
      plan was recalculated in phase images of 4DCT scans. Same strategies were used 
      for plan evaluation except dose-volume histograms of the planning target volumes 
      (PTVs) instead of GTVs were used and the mean and standard deviation of the 
      relative volumes of PTVs covered by 95% of prescribed dose and the ipsilateral 
      lung dose were used to compare different planning strategies. RESULTS: MIP3 plans 
      without treatment uncertainties yielded 96.7% of the mean relative GTV covered by 
      95% of prescribed dose (standard deviations of 5.7% for all cases). With 
      treatment uncertainties, MIP3 plans yielded 99.5% of mean relative PTV covered by 
      95% of prescribed dose (standard deviations of 0.7%). Inclusion of treatment 
      uncertainties improved PTV dose coverage but also increased the ipsilateral mean 
      lung dose in general, and reduced the variations of the PTV dose coverage among 
      different cases. Plans based on conventional axial CT scan (CVCT) gave the 
      poorest PTV dose coverage (about 96% of mean relative PTV covered by 95% isodose) 
      compared to MIP3 and EE plans, which resulted in 100% of PTV covered by 95% 
      isodose for tumors with relatively large motion. AVG plans demonstrated PTV dose 
      coverage of 89.8% and 94.4% for cases with small tumors. MIP3 plans demonstrated 
      superior tumor coverage and were least sensitive to tumor size and tumor 
      location. CONCLUSION: MIP3 plans based on 4DCT scans were the best planning 
      strategy for proton lung treatment planning.
FAU - Wang, Ning
AU  - Wang N
AD  - Department of Radiation Medicine, Loma Linda University Medical Center, Loma 
      Linda, CA 92354, USA. NIWANG@llu.edu
FAU - Patyal, Baldev
AU  - Patyal B
FAU - Ghebremedhin, Abiel
AU  - Ghebremedhin A
FAU - Bush, David
AU  - Bush D
LA  - eng
PT  - Comparative Study
PT  - Journal Article
DEP - 20130325
PL  - England
TA  - Radiat Oncol
JT  - Radiation oncology (London, England)
JID - 101265111
SB  - IM
MH  - Four-Dimensional Computed Tomography/*methods
MH  - Humans
MH  - Lung Neoplasms/diagnostic imaging/*radiotherapy
MH  - Proton Therapy/*methods
MH  - Radiotherapy Planning, Computer-Assisted/*methods
PMC - PMC3652762
EDAT- 2013/03/28 06:00
MHDA- 2014/01/01 06:00
PMCR- 2013/03/25
CRDT- 2013/03/28 06:00
PHST- 2012/11/13 00:00 [received]
PHST- 2013/03/18 00:00 [accepted]
PHST- 2013/03/28 06:00 [entrez]
PHST- 2013/03/28 06:00 [pubmed]
PHST- 2014/01/01 06:00 [medline]
PHST- 2013/03/25 00:00 [pmc-release]
AID - 1748-717X-8-73 [pii]
AID - 10.1186/1748-717X-8-73 [doi]
PST - epublish
SO  - Radiat Oncol. 2013 Mar 25;8:73. doi: 10.1186/1748-717X-8-73.