Page 35 - Towards personalized therapy for metastatic prostate cancer: technical validation of [18F]fluoromethylcholine

All LN showed enhanced FCH uptake at early (2 min p.i.) as well as late (30 min p.i.) time points (Table 2). The long axes of the inguinal and pelvic lymph nodes were similar (11 ±2, and 12 ±3 mm, respectively); short axis diameters were slightly smaller in the former group (8 ±1 vs. 10 ±2 mm, respectively; P < 0.001).
Dual-phase [18F]FCH PET/CT in prostate cancer
Table 2. SUV metrics of lymph nodes as a function of time.
2
Standard Uptake Value (SUV)
Benign N = 17
Malignant N = 37
Total N = 54
Maximum
Early (2 min p.i.) Median
(Range)
Late (30 min p.i.)
Median (Range)
Difference Median
(Range)
Relative Difference
Median (Range) MeanA50
Early (2 min p.i.) Median
(Range)
Late (30 min p.i.)
Median (Range)
Difference Median
(Range)
Relative Difference
Median (Range)
Difference = SUVlate – SUVearly
Relative difference = (SUVlate – SUVearly)/
2
(1.4 – 8.4)
1.4
(0.95 – 4.8)
-0.64
(-3.6 – -0.08)
-0.32
(-0.54 – -0.055)
1.5
(1.1 – 5.6)
1.1
(0.75 – 3.4)
-0.42
(-2.2 – 0.02)
-0.29
(-0.49 – 0.019)
SUVearly
3.5
(1.4 – 10)
4.3
(2.2 – 11)
0.44
(-1.4 – 3.8)
0.084 (-0.25 – 1.4)
2.6
(1.2 – 7.2)
3.4
(1.8 – 8.1)
0.31
(-1 – 2.7)
0.11
(-0.22 – 1.4)
3
(1.4 – 10)
3.2
(0.95 – 11)
0
(-3.6 – 3.8)
0
(-0.54 – 1.4)
2.3
(1.1 – 7.2)
2.6
(0.75 – 8.1)
0.03
(-2.2 – 2.7)
0.013 (-0.49 – 1.4)
We found highly significant associations between the LN status (inguinal/ benign vs. enlarged pelvic/ malignant) and the SUVmax and SUVmeanA50 30 min p.i., and their absolute and relative differences (P < 0.0001). The correlation between the mean and max SUV metrics was near-perfect (Figure 1; the linear regression model resulted in an almost identical relation and an adjusted R2 of 0.99).
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