Endocrine Therapy Initiation among Older Women with Ductal Carcinoma In Situ
Table 1
Characteristics among women with a DCIS diagnosis in relation to use of endocrine therapy, SEER-Medicare, 2007–2011.
Endocrine therapy
No endocrine therapy
HR (95% CI)
HR (95% CI)
Total
1,205
1,740
Age at diagnosis, years
65–69
455
494
1
1
70–74
374
442
0.94 (0.82, 1.08)
0.94 (0.82, 1.07)
75–79
230
396
0.73 (0.63, 0.86)
0.74 (0.63, 0.87)
80-84
146
408
0.49 (0.41, 0.60)
0.55 (0.45, 0.66)
Continuous age at diagnosis (SD)
72.3
74.5
0.96 (0.95, 0.97)
0.97 (0.96, 0.98)
Calendar year of diagnosis
2007
242
324
1
1
2008
244
362
0.92 (0.77, 1.10)
1.03 (0.92, 1.16)
2009
233
370
0.87 (0.72, 1.04)
1.07 (0.95, 1.20)
2010
219
333
0.88 (0.73, 1.06)
1.07 (0.95, 1.21)
2011
267
351
0.99 (0.83, 1.18)
1.04 (0.93, 1.16)
Race
White
1,027
1,458
1
1
Black
96
139
0.97 (0.79, 1.20)
0.87 (0.70, 1.08)
Asian, other or unknown
82
143
0.83 (0.66, 1.04)
1.00 (0.79, 1.27)
Geographic area
Northeast
266
374
0.88 (0.75, 1.04)
0.77 (0.65, 0.92)
Midwest
181
210
1.07 (0.89, 1.29)
0.93 (0.77, 1.12)
West
471
806
0.74 (0.64, 0.85)
0.67 (0.57, 0.78)
South
287
350
1
1
Estrogen receptor (ER) status
ER negative
64
334
1
1
ER positive/borderline
1,023
1,108
3.70 (2.87, 4.76)
3.75 (2.91, 4.83)
ER unknown
118
298
2.02 (1.49, 2.74)
2.12 (1.56, 2.88)
Surgery & radiation
Breast conserving surgery, no radiation
224
475
0.69 (0.59, 0.80)
0.69 (0.59, 0.80)
Breast conserving surgery, radiation
767
753
1
1
Mastectomy
214
512
0.57 (0.49, 0.66)
0.59 (0.51, 0.69)
Grade
1
182
236
1
1
2
499
613
0.95 (0.80, 1.13)
0.95 (0.80, 1.13)
3
368
684
0.70 (0.58, 0.83)
0.88 (0.73, 1.06)
Missing
156
207
0.92 (0.74, 1.13)
0.99 (0.80, 1.23)
Tumor size, mm
≤15
623
843
1
1
16–40
206
351
0.82 (0.70, 0.95)
0.92 (0.79, 1.08)
>40
80
145
0.80 (0.63, 1.00)
0.99 (0.78, 1.26)
Unknown
296
401
0.98 (0.85, 1.12)
1.02 (0.89, 1.18)
Comedo status
No
1,040
1,460
1
1
Yes
165
280
0.84 (0.71, 0.99)
1.01 (0.86, 1.19)
797 tamoxifen users plus 408 aromatase inhibitor users; adjusted for age at diagnosis; adjusted for age at diagnosis, race, ER status, surgery and radiation, and geographic area.
