Table 2

Characteristics of breast cancer cases and their tumors according to whether tumor tissues were available for immunohistochemistry testing

Cases without available tissue (n = 348)Cases with available tissue (n = 826)P
Vital Status
 Alive265 (76.2)597 (72.3)
 Dead83 (23.9)229 (27.7)0.170
Age at diagnosis
 20–2924 (6.9)28 (3.4)
 30–3461 (17.5)126 (15.3)
 35–39142 (40.8)310 (37.5)
 40+121 (34.8)362 (43.8)0.004
AJCC stage
 I129 (39.2)314 (38.2)
 IIA103 (31.3)247 (30.1)
 IIB59 (17.9)166 (20.2)
 IIIA+38 (11.6)95 (11.6)0.850
Tumor size
 <2 cm174 (53.7)434 (52.9)
 >2–5 cm120 (37.0)325 (39.6)
 >5 cm30 (9.3)62 (7.6)0.532
Ever pregnant
 No61 (17.5)128 (15.5)
 Yes287 (82.5)698 (84.5)0.387
Ever had a live/still birth
 No95 (27.3)214 (25.9)
 Yes253 (72.7)612 (74.1)0.621
Number of live/still births
 Nulliparous95 (27.3)214 (25.9)
 154 (15.5)146 (17.7)
 2–3167 (48.0)425 (51.5)
 4+32 (9.2)41 (5.0)0.037
Age at first live/still birth
 Nulliparous95 (27.3)214 (25.9)
 <2062 (17.8)105 (12.7)
 20–29163 (46.8)388 (47.0)
 30+28 (8.1)118 (14.3)0.006
Age at last live/still birth
 Nulliparous95 (27.3)214 (25.9)
 <2010 (2.9)24 (2.9)
 20–29157 (45.1)319 (38.7)
 30+86 (24.7)268 (32.5)0.056
Time since last live/still birth
 Nulliparous95 (27.3)214 (25.9)
 5+ years194 (55.8)467 (56.6)
 2–< 5 years36 (10.3)84 (10.2)
 <2 years23 (6.6)60 (7.3)0.948
Ever had induced abortion
 No264 (75.9)596 (72.2)
 Yes84 (24.1)229 (27.8)0.200
Age at first induced abortion
 Never264 (75.9)596 (72.2)
 <188 (2.3)18 (2.2)
 18+76 (21.8)211 (25.6)0.397