Table 2 IOTA rule and risk of ovarian cancer

Benign Features

 Unilocular cysts (B1)

16

25.40%

45

78.90%

 < 0.01

11.02

4.70

25.85

 Solid components less than 7 mm (B2)

8

12.70%

2

3.5

0.10

0.25

0.05

1.23

 Acoustic shadows (B3)

0

0.00%

0

0.00%

-

-

-

-

 Smooth multilocular tumors less than 10 cm (B4)

29

46.00%

0

0.00%

 < 0.01

0.54

0.43

0.68

 No Blood flow (B5)

54

85.70%

30

52.60%

 < 0.01

0.19

0.08

0.45

Malignant Features

 Irregular tumors (M1)

24

38.10%

56

98.20%

 < 0.01

91.00

11.81

701.05

 Ascites (M2)

1

1.60%

3

5.30%

0.35

3.44

0.35

34.10

 Tumors with more than 3 papillary projections (M3)

1

1.60%

9

15.80%

 < 0.01

11.63

1.42

94.94

 Multilocular tumors > 10 cm with solid components (M4)

2

3.20%

8

14.00%

0.05

4.98

1.01

24.53

 Strong blood flow (M5)

9

14.30%

27

47.40%

 < 0.01

5.4

2.25

12.97

IOTA Simple Rule Risk

18.97%

29.75%

44.74%

34.88%

 < 0.01

-0.27

-0.39

-0.15