Non-OSNA group

OSNA group

(Fishers exact test)

Pre-operative Axillary Status

Negative

128

217

P = 0.34

Positive

9

23

Results of Axillary Surgery (US Neg)

Negative

98

161

P = 0.70

Macro-metastases

28

33

P = 0.14

Micro-metastases

2

23

P = 0.001

Overall Axillary Status

Negative

98

161

P = 0.42

Positive

a) Macro-metastases

37

56

P = 0.457

b) Micro-metastases

2

23

P = 0.001