Table 2 Univariable Cox proportional hazard analysis of relationship between MRI variables and recurrence-free survival

Lesion morphology baseline MRI

0.612

 Mass unifocal

91

10

 Mass multifocal

96

12

1.29

0.71, 3.70

 Non mass (diffuse)

77

13

1.60

0.57, 3.01

 Mass and non mass

8

0

4.38

0.03, 41.66

Pattern of reduction at MRI after NAC

0.029

 No change

23

4

 Shrinking mass

96

10

0.56

0.19, 1.89

 Diffuse decrease

56

10

0.78

0.27, 2.64

 Small foci

53

11

0.95

0.34, 3.19

 No enhancement

44

0

0.06

0, 0.53

Dynamic curve type after NAC

0.008

 No enhancement

44

0

 Continuous

89

16

13.54

1.83, 1728.03

 Plateau

82

5

7.46

0.84, 980.87

 Washout

57

14

17.59

2.35, 2248.46

Radiological complete response

0.004

 Yes

44

0

 No

228

35

12.81

–^a, 1621.10

0.009

 No enhancement after NAC

44

0

 Part Rem (LD initial↓ ≥30 %)

154

23

11.63

–^a, 1477.68

 NR (LD initial↓ <30 %)

74

12

16.53

2.17, 2119.55

RECIST evaluation MRI initial after NAC – during

0.037

 No enhancement during and after NAC

10

0

 No enhancement after NAC

36

0

0.44

0, 80.78

 Part Rem (LD initial↓ ≥30 %)

82

11

3.99

0.52, 513.45

 NR (LD initial ↓ <30 %)

144

24

4.95

0.68, 629.57

RECIST evaluation MRI late after NAC - baseline

0.05

 No washout/plateau baseline and after NAC

8

0

 No washout/plateau after NAC

136

17

3.08

0.41, 394.53

 Part Rem (LD late ↓ ≥30 %)

93

12

3.54

0.46, 455.8

 NR (LD late ↓ <30 %)

35

6

11.57

1.31, 1525.99

RECIST evaluation MRI late after NAC - during

0.46

 No plateau/washout during and after NAC

61

6

 No plateau/washout after NAC

84

11

1.17

0.43, 3.17

 Part Rem (LD late ↓ ≥30 %)

58

9

1.65

0.59, 4.64

 NR (LD late ↓ <30 %)

69

9

2.08

0.74, 5.87