Table 1 IRS classification

0 = no positive cells

0 = no color reaction

0 - 1 = negative

0 = negative

1 = < 10% positive cells

1 = mild reaction

2 - 3 = mild

1 = positive, weak expression

2 = 10-50% positive cells

2 = moderate reaction

4 - 8 = moderate

2 = positive, intermediate expression

3 = 51-80% positive cells

3 = intense reaction

9 - 12 = strongly positive

3 = positive, strong expression

4 = >80% positive cells