Use of Mastectomy for Overdiagnosed Breast Cancer in the United States: Analysis of the SEER 9 Cancer Registries
Table 3
Characteristics of the breast cancer cases not ruled out from being overdiagnoses.
Characteristic
Cases
Treated with mastectomy ()
Risk ratio (95 CI)
Total
20229
5829 (28.8%)
Stage, AJCC
0 (in situ)
4935
1154 (23.4%)
Ref.
I
10627
2966 (27.9%)
1.2 (1.1-1.3)
II
4232
1648 (38.9%)
1.7 (1.6-1.8)
III
0
-
-
IV
0
-
-
NA
426
61 (14.3%)
0.6 (0.5-0.8)
Tumor size, cm
0.0-0.9
5131
1232 (24%)
Ref.
1.0-1.9
7573
2147 (28.4%)
1.2 (1.1-1.3)
2.0-2.9
3439
1253 (36.4%)
1.5 (1.4-1.6)
3.0-3.9
1416
586 (41.4%)
1.7 (1.6-1.9)
4.0-4.9
0
-
-
5.0+
0
-
-
NA
2661
611 (23.0%)
1.0 (0.9-1.0)
Regional lymph nodes positive
0
12917
4422 (34.2%)
Ref.
1
1861
750 (40.3%)
1.2 (1.1-1.3)
2+
0
-
-
NA
5442
657 (12.1%)
0.4 (0.3-0.4)
Grade
I
5035
1208 (24.0%)
Ref.
II
8301
2459 (29.6%)
1.2 (1.2-1.3)
III
5305
1826 (34.4%)
1.4 (1.3-1.5)
IV
116
34 (29.3%)
1.2 (0.9-1.6)
NA
1463
302 (20.6%)
0.9 (0.8-1.0)
Molecular status
HER2− HR− (triple negative)
1398
485 (34.7%)
1.2 (1.1-1.3)
HER2− HR+
11726
3375 (28.8%)
Ref.
HER2+ HR−
521
204 (39.2%)
1.4 (1.2-1.5)
HER2+ HR+
1358
492 (36.2%)
1.3 (1.2-1.4)
NA
5217
1273 (24.4%)
0.8 (0.8-0.9)
Age, years
40-49
3283
1264 (38.5%)
Ref.
50-64
7981
2330 (29.2%)
0.8 (0.7-0.8)
65-84
8057
2054 (25.5%)
0.7 (0.6-0.7)
85+
899
181 (20.1%)
0.5 (0.5-0.6)
Race
American Indian or Alaska Native
138
41 (29.7%)
1.0 (0.8-1.4)
Asian or Pacific Islander
2174
719 (33.1%)
1.2 (1.1-1.2)
Black
2028
576 (28.4%)
1.0 (0.9-1.1)
White
15756
4472 (28.4%)
Ref.
Other and unknown
124
21 (16.9%)
0.6 (0.4-0.9)
NA, not available or not applicable; AJCC, American Joint Committee on Cancer; HR, hormone receptor status (negative if both estrogen and progesterone receptor status are negative, positive if either is positive); HER2, human epidermal growth factor receptor 2 neu status; CI, confidence interval; Ref., reference level. Risk ratios are from univariate analyses and were estimated by unconditional maximum likelihood.
