CTOS 14.11.08 CTOS 14.11.08 Soft Tissue Sarcoma of the Extremity Comparison of Conformal Post- Comparison of Conformal Post- operative Radiotherapy (CRT) and operative Radiotherapy (CRT) and Intensity Modulated Radiotherapy Intensity Modulated Radiotherapy (IMRT) (IMRT) 1 Joint Department of Physics, Royal Marsden NHS Foundation Trust, Sutton, Surrey, UK 2 St Luke’s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey, UK 3 Department of Radiotherapy, Royal Marsden NHS Foundation Trust, Young K Lee 1 , Alexandra J Stewart 2 , Frank H Saran 3
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CTOS 14.11.08 Soft Tissue Sarcoma of the Extremity
CTOS 14.11.08 Soft Tissue Sarcoma of the Extremity Comparison of Conformal Post-operative Radiotherapy (CRT) and Intensity Modulated Radiotherapy (IMRT). Young K Lee 1 , Alexandra J Stewart 2 , Frank H Saran 3. - PowerPoint PPT Presentation
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CTOS 14.11.08CTOS 14.11.08
Soft Tissue Sarcoma of the Extremity
Comparison of Conformal Post-operative Comparison of Conformal Post-operative Radiotherapy (CRT) and Intensity Modulated Radiotherapy (CRT) and Intensity Modulated
Radiotherapy (IMRT)Radiotherapy (IMRT)
1Joint Department of Physics, Royal Marsden NHS Foundation Trust, Sutton, Surrey, UK2St Luke’s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey, UK3Department of Radiotherapy, Royal Marsden NHS Foundation Trust, Sutton, Surrey, UK
Young K Lee1, Alexandra J Stewart2, Frank H Saran3
BackgroundBackground
Materials and MethodsMaterials and Methods
ResultsResults
SummarySummary
CRT and IMRT for extremity STSCRT and IMRT for extremity STS
BackgroundBackground
Materials and MethodsMaterials and Methods
ResultsResults
SummarySummary
CRT and IMRT for extremity STSCRT and IMRT for extremity STS
BackgroundBackground
Limb-sparing surgery in combination with focal Limb-sparing surgery in combination with focal radiotherapy - standard of care in patients with radiotherapy - standard of care in patients with intermediate and high grade limb and limb girdle intermediate and high grade limb and limb girdle soft tissue sarcomas (STS)soft tissue sarcomas (STS)
Normal tissue toxicity increases with escalating Normal tissue toxicity increases with escalating total and integral dosetotal and integral dose
Dose prescription limited by organs-at-risk (OAR) Dose prescription limited by organs-at-risk (OAR) surrounding the PTVsurrounding the PTV
AimsAims
To define a reproducible and comparable target To define a reproducible and comparable target volume definition for CT planningvolume definition for CT planning
To define reproducible prospective planning dose To define reproducible prospective planning dose volume constraintsvolume constraints
To assess the ability of inversely-planned IMRT To assess the ability of inversely-planned IMRT plans to minimise the dose to surrounding OARplans to minimise the dose to surrounding OAR
To assess efficacy of ‘simple’ IMRT compared to To assess efficacy of ‘simple’ IMRT compared to ‘complex’ IMRT planning‘complex’ IMRT planning
BackgroundBackground
Materials and MethodsMaterials and Methods
ResultsResults
SummarySummary
CRT and IMRT for extremity STSCRT and IMRT for extremity STS
Patient dataPatient data
TT22 and G and G2/32/3 STS of the thigh (n=10) STS of the thigh (n=10)
No tumours invading boneNo tumours invading bone
Entire surgical scar and all drain sites markedEntire surgical scar and all drain sites marked
PTVPTV11 = tumour bed + 5cm SI and 3cm = tumour bed + 5cm SI and 3cm
circumferentially circumferentially
Phase II volumePhase II volume
PTVPTV22 = tumour bed + 2cm isotropically = tumour bed + 2cm isotropically
OAR defined as whole femur, neurovascular OAR defined as whole femur, neurovascular bundle, normal tissue corridor and normal tissue bundle, normal tissue corridor and normal tissue outside PTVoutside PTV11
HOWEVER, 4/5f IMRT resulted in significantly HOWEVER, 4/5f IMRT resulted in significantly lower femur Vlower femur V4545 when compared directly to 2/3f when compared directly to 2/3f
IMRT (p=0.04)IMRT (p=0.04)
BackgroundBackground
Materials and MethodsMaterials and Methods
ResultsResults
SummarySummary
CRT and IMRT for extremity STSCRT and IMRT for extremity STS
SummarySummary
Reproducible, comprehensive planning guidelines Reproducible, comprehensive planning guidelines and dose-volume constraints for 3D planning for and dose-volume constraints for 3D planning for extremity sarcomas devised extremity sarcomas devised
4/5f IMRT plan - lowest clinically relevant doses to 4/5f IMRT plan - lowest clinically relevant doses to OAR whilst delivering conformal doses to PTVOAR whilst delivering conformal doses to PTV
Large primary tumour Large primary tumour
• 4/5f preferable to a 2/3f IMRT approach4/5f preferable to a 2/3f IMRT approach
• 3D-CRT may provide adequate treatment without 3D-CRT may provide adequate treatment without added cost and complexityadded cost and complexity
Results from this study may not be directly Results from this study may not be directly translated to all other primary locations of STS of translated to all other primary locations of STS of the extremitythe extremity
IMRT approach should be assessed prospectively IMRT approach should be assessed prospectively with respect to late toxicity within the confines of with respect to late toxicity within the confines of a prospective clinical triala prospective clinical trial
Further workFurther work
Radiotherapy DepartmentRoyal Marsden NHS Foundation Trust