PMID- 22294198
OWN - NLM
STAT- MEDLINE
DCOM- 20120627
LR  - 20220419
IS  - 1439-099X (Electronic)
IS  - 0179-7158 (Linking)
VI  - 188
IP  - 3
DP  - 2012 Mar
TI  - Adaptive radiotherapy for soft tissue changes during helical tomotherapy for head 
      and neck cancer.
PG  - 243-7
LID - 10.1007/s00066-011-0041-8 [doi]
AB  - PURPOSE: The goal of the present study was to assess the frequency and impact of 
      replanning triggered solely by soft tissue changes observed on the daily setup 
      mega-voltage CT (MVCT) in head and neck cancer (H&N) helical tomotherapy (HT). 
      MATERIAL AND METHODS: A total of 11 patients underwent adaptive radiotherapy 
      (ART) using MVCT. Preconditions were a soft tissue change > 0.5 cm and a tight 
      mask. The dose-volume histograms (DVHs) derived from the initial planning kVCT 
      (inPlan), the recalculated DVHs of the fraction (fx) when replanning was decided 
      (actSit) and the DVHs of the new plan (adaptPlan) were compared. Assessed were 
      the following: maximum dose (Dmax), minimum dose (Dmin), and mean dose (Dmean) to 
      the planning target volume (PTV) normalized to the prescribed dose; the Dmean/fx 
      to the parotid glands (PG), oral cavity (OC), and larynx (Lx); and the Dmax/fx to 
      the spinal cord (SC) in Gy/fx. RESULTS: No patient had palpable soft tissue 
      changes. The median weight loss at the moment of replanning was 2.3 kg. The 
      median PTV Dmean was 100% for inPlan, 103% for actSit, and 100% for adaptPlan. 
      The PTV was always covered by the prescribed dose. A statistically significant 
      increase was noted for all organs at risk (OAR) in the actSit. The Dmean to the 
      Lx, the Dmean to the OC and the Dmax to the SC were statistically better in the 
      adaptPlan. No statistically significant improvement was achieved by ART for the 
      PGs. No significant correlations between weight and volume loss or between the 
      volume changes of the organs to each other were observed, except a strong 
      positive correlation of the shrinkage of the PGs (rho = + 0.77, p = 0.005). 
      CONCLUSION: Soft tissue shrinkage without clinical palpable changes will not 
      affect the coverage of the PTV, but translates into a higher delivered dose to 
      the PTV itself and the normal tissue outside the PTV. The gain by ART in 
      individual patients-especially in patients who receive doses close to the 
      tolerance doses of the OAR-could be substantial.
FAU - Duma, M N
AU  - Duma MN
AD  - Department of Radiation Oncology, Technische Universitat Munchen, Klinikum rechts 
      der Isar, Munich. Marciana.Duma@lrz.tu-muenchen.de
FAU - Kampfer, S
AU  - Kampfer S
FAU - Schuster, T
AU  - Schuster T
FAU - Winkler, C
AU  - Winkler C
FAU - Geinitz, H
AU  - Geinitz H
LA  - eng
PT  - Journal Article
PL  - Germany
TA  - Strahlenther Onkol
JT  - Strahlentherapie und Onkologie : Organ der Deutschen Rontgengesellschaft ... [et 
      al]
JID - 8603469
SB  - IM
MH  - Head and Neck Neoplasms/*radiotherapy
MH  - Humans
MH  - Radiotherapy Dosage
MH  - Radiotherapy Planning, Computer-Assisted
MH  - *Radiotherapy, Intensity-Modulated
MH  - *Tomography, Spiral Computed
MH  - Tumor Burden
MH  - Weight Loss
EDAT- 2012/02/02 06:00
MHDA- 2012/06/28 06:00
CRDT- 2012/02/02 06:00
PHST- 2011/06/27 00:00 [received]
PHST- 2011/11/23 00:00 [accepted]
PHST- 2012/02/02 06:00 [entrez]
PHST- 2012/02/02 06:00 [pubmed]
PHST- 2012/06/28 06:00 [medline]
AID - 10.1007/s00066-011-0041-8 [doi]
PST - ppublish
SO  - Strahlenther Onkol. 2012 Mar;188(3):243-7. doi: 10.1007/s00066-011-0041-8.