Table 1.

Breast cancer tumor characteristics by age

Age < 45 (n = 529)Age ≥ 45 (n = 1,534)
n (%)n (%)
ER Status
 Positive219 (59.2%)804 (67.6%)
 Negative151 (40.8%)385 (32.4%)
SEER Stage
 Localized225 (49.7%)832 (64.6%)
 Regional211 (46.6%)401 (31.1%)
 Distant17 (3.8%)55 (4.3%)
Grade
 Well differentiated36 (8.5%)187 (15.2%)
 Moderately differentiated146 (34.4%)473 (38.4%)
 Poorly or undifferentiated243 (57.2%)571 (46.4%)
Tumor size
 ≤1.0 cm81 (19.8%)339 (27.7%)
 >1–2.0 cm135 (32.9%)474 (38.7%)
 >2 cm194 (47.3%)411 (33.6%)
  • NOTE: ER status was unknown or missing for 159 cases <45 years and 345 cases ≥45 years; SEER stage was unknown or missing for 76 cases <45 years and 246 cases ≥45 years; grade was unknown or missing for 104 cases <45 years and 303 cases ≥45 years; tumor size was missing for 119 cases <45 years and 310 cases ≥45 years.