PMID- 10863085
OWN - NLM
STAT- MEDLINE
DCOM- 20000731
LR  - 20190708
IS  - 0360-3016 (Print)
IS  - 0360-3016 (Linking)
VI  - 47
IP  - 4
DP  - 2000 Jul 1
TI  - Optimizing radiotherapy of orbital and paraorbital tumors: intensity-modulated 
      X-ray beams vs. intensity-modulated proton beams.
PG  - 1111-9
AB  - PURPOSE: This study presents a dosimetric optimization effort aiming to compare 
      intensity-modulated (IM) X-rays and IM protons in 4 different orbital and 
      paraorbital tumors. These are most challenging targets for standard radiotherapy 
      due to their close relationship with the eyes and related structures. METHODS AND 
      MATERIALS: A primary orbital lymphoma, an optic nerve meningioma, a sphenoidal 
      ridge meningioma protruding into the orbit, and a pediatric parameningeal 
      paraorbital rhabdomyosarcoma were selected for the purpose of this study. 
      Planning target volumes (PTVs) and organs at risk (OAR) were defined in each 
      patient CT data set for each tumor site. IM X-ray and IM proton three-dimensional 
      treatment plans were implemented. The following total tumor doses were 
      prescribed: 30 Gy for the orbital lymphoma, 54 Gy for both meningiomas, and 50.4 
      Gy for the rhabdomyosarcoma case. Dose-volume histograms (DVHs) were obtained for 
      all targets and OAR with both treatment techniques. DVHs were used to predict 
      normal tissue complication probabilities (NTCPs) for the OAR in the vicinity of 
      the tumor. RESULTS: The PTV coverage was optimal and equally homogeneous with 
      both IM X-rays and IM proton plans in the 4 tumor sites. DVHs for most OAR were 
      better with IM proton beams especially in the low- to mid-dose range region. The 
      integral nontarget dose was lower with IM protons in every case (factor ranging 
      from 1.5 to 1.9). However, predicted NTCPs (for severe late effects) were equally 
      low for both treatment techniques in every tumor site. CONCLUSION: Although IM 
      proton plans optimally decreased the dose to the OAR in all tumor sites, both 
      optimized X-ray and proton beams equally succeeded to reduce severe-toxicity 
      prediction risks to less than 5% while optimally treating the PTV.
FAU - Miralbell, R
AU  - Miralbell R
AD  - Division de Radio-Oncologie, Hopitaux Universitaires, Geneve, Switzerland. 
      Raymond.Miralbell@hcuge.ch
FAU - Cella, L
AU  - Cella L
FAU - Weber, D
AU  - Weber D
FAU - Lomax, A
AU  - Lomax A
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PL  - United States
TA  - Int J Radiat Oncol Biol Phys
JT  - International journal of radiation oncology, biology, physics
JID - 7603616
RN  - 0 (Protons)
SB  - IM
MH  - Humans
MH  - Meningioma/diagnostic imaging/*radiotherapy
MH  - Optic Nerve Neoplasms/diagnostic imaging/*radiotherapy
MH  - Orbit
MH  - Orbital Neoplasms/diagnostic imaging/*radiotherapy
MH  - *Proton Therapy
MH  - Radiotherapy, Conformal/*methods/standards
MH  - Rhabdomyosarcoma/*radiotherapy
MH  - Skull Neoplasms/diagnostic imaging/*radiotherapy
MH  - *Sphenoid Bone/diagnostic imaging
MH  - Tomography, X-Ray Computed
EDAT- 2000/06/23 11:00
MHDA- 2000/08/06 11:00
CRDT- 2000/06/23 11:00
PHST- 2000/06/23 11:00 [pubmed]
PHST- 2000/08/06 11:00 [medline]
PHST- 2000/06/23 11:00 [entrez]
AID - S0360-3016(00)00494-6 [pii]
AID - 10.1016/s0360-3016(00)00494-6 [doi]
PST - ppublish
SO  - Int J Radiat Oncol Biol Phys. 2000 Jul 1;47(4):1111-9. doi: 
      10.1016/s0360-3016(00)00494-6.