Table 2.

Proliferation indices by EGFR and/or HER-2 positivity (worst tissue samples)

Receptor positivity, average % positivity (SD)*Receptor negativity, average % positivity (SD)Difference
Difference (95% confidence interval)P
EGFR§
    Ki-6748.8 (28.0)25.5 (28.1)23.3 (12.3-34.4)<0.001
    MCM285.9 (23.0)68.0 (32.2)17.8 (5.9-29.7)0.004
HER-2
    Ki-6746.2 (28.8)10.0 (14.1)36.2 (26.5-45.9)<0.001
    MCM284.6 (23.6)50.1 (34.8)34.5 (13.2-55.8)0.004
  • * Samples in which EGFR or HER-2 is overexpressed (score = 2).

  • Samples in which EGFR or HER-2 is not overexpressed (score = 0/1).

  • P values test the differences between the levels of Ki-67 and MCM2 in biopsies with high (receptor positivity) versus low (receptor negativity) receptor expression.

  • § n = 99 for receptor-positive samples (except Ki-67, n = 98) and n = 35 for receptor-negative samples.

  • n = 121 for receptor-positive samples (except Ki-67, n = 120) and n = 13 for receptor-negative samples.