Table 5.

Axillary lymph node variables stratified by tumor size, according to breast tumor subtype

Basal-likeLuminal ALuminal BHER2+/ERUnclassified
(n = 199)(n = 608)(n = 111)(n = 69)(n = 132)
Lymph node status, % positive tumors (n)
 ≤2 cm30 (70)19 (329)35 (57)23 (22)21 (63)
 >2–5 cm41 (106)54 (228)61 (44)59 (37)47 (51)
 >5 cm57 (21)79 (48)86 (7)100 (10)56 (18)
P valuea0.07<0.00010.0040.00020.002
Number of positive lymph nodes, mean (median)
 ≤2 cm1.4 (0)0.7 (0)1.4 (0)0.5 (0)1.3 (0)
 >2–5 cm1.8 (0)2.2 (1.0)3.1 (1.0)3.2 (1.0)2.5 (0)
 >5 cm4.0 (1.0)5.4 (2.0)7.6 (4.0)6.3 (6.0)4.1 (1.0)
P valueb0.04<0.00010.001<0.00010.002
% positive lymph nodes, mean (median)
 ≤2 cm13% (0)5% (0)13% (0)5% (0)10% (0)
 >2–5 cm14% (0)19% (7%)19% (10%)19% (11%)22% (4%)
 >5 cm24% (8%)34% (18%)46% (54%)47% (42%)29% (7%)
P valueb0.17<0.00010.005<0.00010.007
  • aChi-square test (%) comparing categories of tumor size.

  • bWilcoxon rank-sum test (medians) comparing categories of tumor size.