Table 3.

Functional tumor volume (FTV) measurements by neoadjuvant systemic therapy response status.

Measurement	Optimal Threshold		AUC [95% CI]	p-Value	Mean ± SD (cm3)		Best Cutoff for ROC Curve
	PE (%)	SER			Non-pCR (N = 51)	pCR (N = 49)
FTV at 1 min
BL	220	0.25	0.63 [0.52−0.74]	0.029	4.22 ± 9.30	1.25 ± 2.67	3.84
C2	20	0.55	0.80 [0.70−0.89]	<0.001	4.22 ± 5.58	1.60 ± 3.69	1.40
C4	30	0.40	0.84 [0.76−0.92]	<0.001	2.74 ± 5.58	1.05 ± 3.82	0.12
%C2/BL	0	0	0.75 [0.65−0.85]	<0.001	−48.01 ± 34.09	−64.94 ± 55.90	−71.19
%C4/BL	35	0.35	0.78 [0.68−0.87]	<0.001	−72.64 ± 27.11	−90.56 ± 18.59	−92.75
FTV at 2.5 min
BL	0	0.30	0.62 [0.51−0.73]	0.040	14.66 ± 15.43	11.16 ± 26.67	17.18
C2	60	0.90	0.82 [0.73−0.90]	<0.001	3.76 ± 4.89	1.39 ± 3.55	0.56
C4	125	0.75	0.82 [0.73−0.91]	<0.001	0.93 ± 1.48	0.49 ± 2.10	0.09
%C2/BL	0	1.00	0.78 [0.68−0.87]	<0.001	−47.06 ± 39.97	−76.96 ± 26.16	−86.11
%C4/BL	125	0.70	0.79 [0.70−0.88]	<0.001	−71.15 ± 39.99	−92.07 ± 20.65	−98.48

PE, percentage enhancement; SER, signal enhancement ratio; SD, standard deviation; pCR, pathologic complete response; BL, baseline; C2, after 2 cycles of neoadjuvant systemic therapy (NAST); C4, after 4 cycles of NAST; %C2/BL, change between baseline and C2; %C4/BL, change between baseline and C4.