PMID- 20831498
OWN - NLM
STAT- MEDLINE
DCOM- 20110207
LR  - 20161125
IS  - 1651-226X (Electronic)
IS  - 0284-186X (Linking)
VI  - 49
IP  - 7
DP  - 2010 Oct
TI  - A comparison of three different adaptive strategies in image-guided radiotherapy 
      of bladder cancer.
PG  - 1069-76
LID - 10.3109/0284186X.2010.501813 [doi]
AB  - The urinary bladder shows considerable individual variation in shape and position 
      during a course of radiotherapy (RT). In this study we have developed and 
      compared three different adaptive RT (ART) strategies for bladder cancer 
      involving daily cone beam CT (CBCT) imaging and plan selection. MATERIAL AND 
      METHODS: Ten patients treated for bladder cancer had daily CBCTs acquired that 
      were registered online using bony anatomy registration. Seven patients received 
      intensity modulated RT (IMRT) with a simultaneous integrated boost (SIB) 
      technique to the bladder and pelvic lymph nodes. Three patients received 
      treatment to the bladder only. Retrospectively, we compared three ART strategies 
      that were all based on daily selection of the most suitable plan from a library 
      consisting of three IMRT-plans corresponding to a small, medium and large target 
      volume. ART method A utilised population-based margins while methods B and C used 
      the bladder as seen on CBCT-scans from the first week of treatment; method B 
      without delineation of the bladder on CBCT and method C with delineation of the 
      bladder. Total dose distributions were calculated using the planning CT. For each 
      patient, we calculated ratios of the dose volume histograms (DVHs) for the three 
      ART strategies relative to non-adaptive therapy. RESULTS: The inter-patient 
      variation was large for all three ART strategies. The mean ratios of the volumes 
      receiving 57 Gy or more (corresponding to 95% of prescribed dose) for methods A, 
      B and C were 0.66 (SD: 0.11), 0.67 (SD: 0.13) and 0.67 (SD: 0.16) respectively 
      when compared to the non-adaptive plan. CONCLUSION: When using any of the ART 
      strategies, it is possible to reduce significantly the volumes receiving high 
      doses compared to the use of a standard non-adaptive plan. The differences in 
      dose volume parameters between the three methods were small compared with the 
      differences from the standard plan.
FAU - Vestergaard, Anne
AU  - Vestergaard A
AD  - Department of Medical Physics, Aarhus University Hospital - Arhus Sygehus, 
      DK-8000 Aarhus C, Denmark. annveste@rm.dk
FAU - Sondergaard, Jimmi
AU  - Sondergaard J
FAU - Petersen, Jorgen B
AU  - Petersen JB
FAU - Hoyer, Morten
AU  - Hoyer M
FAU - Muren, Ludvig Paul
AU  - Muren LP
LA  - eng
PT  - Clinical Trial
PT  - Comparative Study
PT  - Journal Article
PL  - Sweden
TA  - Acta Oncol
JT  - Acta oncologica (Stockholm, Sweden)
JID - 8709065
SB  - IM
MH  - Aged
MH  - Aged, 80 and over
MH  - Carcinoma/*diagnostic imaging/pathology/*radiotherapy
MH  - Cone-Beam Computed Tomography/*methods
MH  - Dose-Response Relationship, Radiation
MH  - Humans
MH  - Imaging, Three-Dimensional/methods
MH  - Male
MH  - Organ Size
MH  - Radiotherapy Dosage
MH  - Radiotherapy Planning, Computer-Assisted/*methods
MH  - Radiotherapy, Conformal/methods
MH  - Tumor Burden/radiation effects
MH  - Urinary Bladder/pathology/radiation effects
MH  - Urinary Bladder Neoplasms/*diagnostic imaging/pathology/*radiotherapy
EDAT- 2010/09/14 06:00
MHDA- 2011/02/08 06:00
CRDT- 2010/09/14 06:00
PHST- 2010/09/14 06:00 [entrez]
PHST- 2010/09/14 06:00 [pubmed]
PHST- 2011/02/08 06:00 [medline]
AID - 10.3109/0284186X.2010.501813 [doi]
PST - ppublish
SO  - Acta Oncol. 2010 Oct;49(7):1069-76. doi: 10.3109/0284186X.2010.501813.