Quantitative dynamic ¹⁸FDG-PET and tracer kinetic analysis of soft tissue sarcomas

Figures & data

Table I. Patient cohort.

Patient	Histology, grade	Tumor location	Tumor volume (cm^3)	Treatment	Clinical status
1	Leiomyosarcoma, III	Right thigh (Adductor)	126	S	DOD
2	Leiomyosarcoma, III	Near liver (Para portal)	38	RT	SD
3	Pleomorphic undifferentiated sarcoma, IV	Left buttock (Posterior to gluteus maximus)	189	S	DOD
4	Liposarcoma, III	Near left knee joint (Proximal and medial)	311	S	NED
5	Pleomorphic undifferentiated sarcoma, IV	Left shoulder blade (Superior and posterior to scapula)	408	RT	DOD
6	Leiomyosarcoma, IV	Left calf (Gastrocnemius)	48	S	NED
7	Myxofibrosarcoma, IV	Right thigh (Proximal, anterior to femur)	231	S	NED
8	Leiomyosarcoma, III	Right hip (Inguinal)	56	S	NED
9	Schwannoma, III/IV	Right knee (Proximal and lateral to fibula)	511	RT	DOD
10	Leiomyosarcoma, III	Shoulder (Proximal and lateral to humerus)	252	RT	SD
11	Leiomyosarcoma, IV	Back (Posterior of angulus scapula)	86	S	NED

DOD, dead of disease; NED, no evidence of disease; RT, definitive radiotherapy; S, surgery and post-operative radiotherapy; SD, stable disease.

Figure 1. Dynamic ¹⁸FDG-PET sequence for patient 11 post injection showing the temporal evolution of the FDG activity. The tumor border is marked with a green line.

Figure 2. Time activity curves for patients 1-11 post injection showing the temporal development of the SUV peak value.

Figure 3. Two selected voxel elements for patient 10 post injection. Data points are averaged over the voxel in question and its six closest voxels. “Free” is non-metabolized ¹⁸FDG, “bound” is metabolized ¹⁸FDG, and “vascular” is the fraction of the plasma function included in the voxel element. Estimated pharmacokinetic parameters are given.

Figure 4. Parameter maps for patient 11 derived from the pharmacokinetic analysis. In addition, two static snapshot PET images obtained 2 and 45 min p.i. are shown. The tumor border is marked with a green line.

Figure 5. Patient-averaged histograms over the relevant PET-derived parameters. The dashed lines indicate one standard deviation.

Table II. Summary of PET-derived values.

Patient	SUVE	SUVL	K1 (min^−1)	k2 (min^−1)	k3 (min^−1)	MRFDG (min^−1)	νp
1	3.3	5.9	0.31	0.66	0.087	0.033	0.15
2	6.0	4.3	0.54	1.07	0.032	0.012	0.27
3	1.5	2.5	0.19	0.54	0.032	0.007	0.07
4	2.1	3.3	0.20	0.25	0.017	0.009	0.14
5	3.0	8.1	0.39	0.73	0.16	0.062	0.18
6	2.9	4.4	0.27	0.79	0.088	0.026	0.12
7	5.8	5.0	0.59	0.94	0.056	0.021	0.27
8	4.4	16.3	0.61	1.14	0.283	0.126	0.25
9	2.8	13.1	0.27	2.03	0.95	0.088	0.11
10	3.7	3.0	0.19	0.56	0.071	0.016	0.20
11	5.4	4.7	0.97	2.41	0.174	0.025	0.20

MR_FDG, metabolic rate of ¹⁸FDG; SUV_E, peak standard uptake value 2 minutes post injection; SUV_L, peak standard uptake value 45 minutes post injection; ν_p, vascular fraction.