Practical Considerations for Integrating PET/CT into Radiation Therapy Planning

Article Figures & Data

Download figure
Open in new tab
Download powerpoint
FIGURE 1.
Radiation pallet placed on PET/CT table with face mask and beanbag stabilizer. Four-dimensional laser system is also seen. This is what a common setup looks like when using PET/CT system to perform radiation therapy imaging.
Download figure
Open in new tab
Download powerpoint
FIGURE 2.
Abdominal mass example in which PET/CT imaging was used to aid in drawing treatment-planning contours. ¹⁸F-FDG uptake visualized by PET/CT is used to determine gross tumor volume, shown in yellow. Area in dark blue is clinical tumor volume, defined as gross tumor plus microscopic disease. Cyan outline is planning target volume, which includes clinical tumor volume plus margin for daily treatment setup and patient positioning.
Download figure
Open in new tab
Download powerpoint
FIGURE 3.
Example of intratreatment use of PET/CT imaging for head-and-neck patient who presented with initial disease. Because of weight loss, patient had to have new face mask made and follow-up CT. Original PET/CT images were registered to new CT images, allowing patient to continue treatment without any breaks.
Download figure
Open in new tab
Download powerpoint
FIGURE 4.
Example head-and-neck patient, with top images showing pretreatment volumes, middle images showing 1-y PET/CT follow-up, and bottom images showing new treatment volumes while using PET/CT image

TABLE 1

Differences in Efficiency of Radiation Therapy Workflow With Versus Without PET/CT for Planning

Workflow for initial treatment				Workflow for prior treatment
Without PET/CT		With PET/CT		Without PET/CT		With PET/CT
Task	Time (min)	Task	Time (min)	Task	Time (min)	Task	Time (min)
Import images	3	Import images	3	Import images	3	Import images	3
Image registration^*	20	Image registration^†	3	Image registration^*	20	Rigid registration	10
Verify registration	20	Verify registration	4	Verify registration	20	Verify registration	20
				Transfer/deform contours	30	Transfer contours	10
				Verify contours on new CT	10	Verify contours on new CT	10
				Deform prior dose to current CT	10
				Verify dose transfer to new CT	10
Import images into planning software	4			Import images into planning software	4
Contour	240	Contour	120	Contour	240	Contour	240
Planning	1,440	Planning	1,440	Planning	1,440	Planning	1,440
				Insert plan sum	5	Insert plan sum	5
				Evaluate plan summation	10	Evaluate plan summation	10
Total time	1,727	Total time	1,570	Total time	1,802	Total time	1,748