Table 1 Patient baseline and disease characteristics of Kaiser Permanente Northern California Cohort (KPNC) Stage I–III breast cancers, diagnosed 2000–2010

Age (years)

21–34

302 (1.5%)

13 (1.5%)

3 (0.4%)

35–39

571 (2.8%)

36 (4.3%)

8 (1.2%)

40–44

1340 (6.6%)

65 (7.7%)

12 (1.7%)

45–49

2167 (10.6%)

81 (9.6%)

21 (3.0%)

50–54

2604 (12.7%)

90 (10.7%)

33 (4.7%)

55–59

2962 (14.5%)

104 (12.4%)

39 (5.6%)

60–64

2866 (14.0%)

106 (12.6%)

52 (7.5%)

65–69

2482 (12.1%)

78 (9.3%)

71 (10.2%)

70–74

2004 (9.8%)

81 (9.6%)

109 (15.7%)

75 + 

3164 (15.5%)

188 (22.3%)

348 (50.0%)

Race

Non-Hispanic White

14,181 (69.3%)

601 (71.4%)

531 (76.3%)

Hispanic White

1985 (9.7%)

77 (9.1%)

38 (5.5%)

Non-Hispanic Black

1500 (7.3%)

81(9.6%)

85 (12.2%)

Hispanic Black

7 (< 0.1%)

0

0

Asian/Pacific Islander

2719 (13.3%)

80 (9.5%)

40 (5.8%)

Other/Unknown

70 (0.3%)

3 (0.4%)

2 (0.2%)

Smoking status at diagnosis

Current smoker

2430 (11.9%)

109 (13.0%)

126 (18.1%)

Former smoker

3095 (24.0%)

100 (11.9%)

97 (13.9%)

Non-smoker

7389 (36.1%)

162 (19.2%)

97 (13.9%)

Unknown

7548 (36.9%)

471 (55.9%)

376 (54.0%)

Diabetes

2669 (13.1%)

104 (12.4%)

160 (23.0%)

Charlson comorbidity

0

13,130 (64.2%)

544 (64.6%)

277 (39.8%)

1–2

6137 (30.0%)

240 (28.5%)

288 (41.4%)

3 + 

1163 (5.7%)

56 (6.7%)

130 (18.7%)

unknown

32 (0.2%)

2 (0.2%)

1 (0.1%)

Breast Cancer Characteristics

Bilateral

Unilateral—Right

Unilateral-Left

Unilateral—Unknown

138 (0.7%)

9842 (48.1%)

10,476 (51.2%)

6 (< .01%)

4 (0.5%)

8 (1.2%)

Surgery

None

560 (2.7%)

59 (7.0%)

39 (5.6%)

Lumpectomy

11,583 (56.6%)

270 (32.1%)

321 (46.1%)

Mastectomy

8309 (40.6%)

512 (60.8%)

334 (48.0%)

Unknown

10 (0.1%)

1 (0.1%)

2 (0.3%)

Grade

1 Well differentiated

4734 (23.1%)

37 (4.4%)

130 (18.7%)

2 Moderately differentiated

8336 (40.7%)

287 (34.1%)

272 (39.1%)

3 Poorly differentiated

5481(26.8%)

424 (50.4%)

198 (28.5%)

4 Diffuse

259 (1.3%)

20 (2.4%)

7 (1.0%)

Unknown

1652 (8.1%)

74 (8.8%)

89 (12.8%)

Stage

1

10,843 (53.0%)

127 (15.1%)

294 (42.3%)

2

7806 (38.2%)

444 (52.7%)

316 (45.4%)

3

1813 (8.9%)

271 (32.2%)

86 (12.4%)

Tumor size

 ≤ 2 cm

13,727 (67.1%)

269 (32.0%)

393 (56.5%)

(2,5] cm

5723 (28.0%)

411 (48.8%)

244 (35.1%)

 > 5 cm

838 (4.1%)

117 (13.9%)

44 (6.3%)

Diffuse or Unknown

174 (0.9%)

45 (5.3%)

15 (2.2%)

ER/PR

Positive

11,917 (58.2%)

393 (46.7%)

442 (63.5%)

Negative

2689 (13.1%)

253 (30.1%)

105 (15.1%)

Unknown/not done

5856 (28.6%)

196 (23.3%)

149 (21.4%)

HER2

Positive

1862 (9.1%)

110 (13.1%)

49 (7.0%)

Negative

11,938 (58.3%)

422 (50.1%)

417 (59.9%)

Unknown/not done

6662 (32.6%)

310 (36.8%)

230 (33.1%)

Positive Lymph Nodes

0

14,150 (69.2%)

327 (71.1%)

449 (64.5%)

1–3

4429 (21.7%)

234 (21.3%)

156 (22.4%)

 > 3

1851 (9.1%)

279 (7.5%)

87 (12.5%)

None examined/unknown

32 (0.2%)

2 (0.1%)

4 (0.6%)

Treatments received

Any chemotherapy

9639 (47.1%)

596 (70.8%)

204 (29.3%)

Taxanes

2806 (13.7%)

220 (26.1%)

47 (6.8%)

Targeted Therapy

1206 (5.9%)

78 (9.3%)

16 (2.3%)

Alkylating Agents

1626 (8.0%)

113 (13.4%)

41 (5.9%)

Antimetabolites

1061 (5.2%)

174 (20.7%)

33 (4.7%)

Vinca Alkaloids

364 (1.8%)

94 (11.2%)

14 (2.0%)

Other

1174 (5.7%)

133 (15.8%)

23 (3.3%)

No Chemotherapy

10,823 (52.9%)

246 (29.2%)

492 (70.7%)

Any hormonal therapy

8463 (41.4%)

265 (31.5%)

282 (40.5%)

Any radiation

6621(32.4%)

247(29.3%)

184 (26.4%)