Skip to main content

Table 2 Associations of tumor characteristics and treatment modes with primary breast cancer as the second malignancy (BCa-2): a SEER population-based study in US, 1990–2015

From: Increased risk of breast cancer-specific mortality among cancer survivors who developed breast cancer as a second malignancy

 

BCa-1

BCa-2

N (%)

N (%)

OR (95% CI) a

Histology

 Ductal

643,139 (72.8)

25,487 (70.2)

1.00

 Lobular

73,112 (8.3)

3456 (9.5)

1.01 (0.97–1.05)

 Mixed

82,546 (9.3)

3439 (9.5)

1.02 (0.98–1.06)

 Others

85,084 (9.6)

3931 (10.8)

1.04 (1.00–1.08)

Tumor grade

 Well differentiated

165,869 (18.8)

7817 (21.5)

1.00

 Moderately differentiated

337,563 (38.2)

14,526 (40.0)

0.97 (0.94–1.00)

 Poorly differentiated

277,729 (31.4)

9435 (26.0)

0.91 (0.88–0.94)

 Undifferentiated

9863 (1.1)

266 (0.7)

0.86 (0.76–0.98)

Tumor size

 0-2 cm

506,784 (57.3)

22,629 (62.3)

1.00

 2-5 cm

260,786 (29.5)

9608 (26.5)

0.85 (0.83–0.87)

  > 5 cm

66,236 (7.5)

1884 (5.2)

0.67 (0.64–0.71)

Tumor stage

 Local

547,036 (61.9)

24,624 (67.8)

1.00

 Regional

265,617 (30.1)

8815 (24.3)

0.86 (0.84–0.88)

 Distant

57,578 (6.5)

2065 (5.7)

0.79 (0.75–0.83)

Molecular subtypesc

 HR+/HER2-

205,424 (67.4)

11,106 (70.4)

1.00

 HR+/HER2+

30,893 (10.1)

1283 (8.1)

0.93 (0.88–0.99)

 HR−/HER2+

13,507 (4.4)

492 (3.1)

0.82 (0.75–0.90)

 Triple negative

32,172 (10.6)

1481 (9.4)

1.00 (0.94–1.05)

 

N (%)

N (%)

OR (95% CI) b

Surgery d

 No

60,648 (7.8)

3712 (11.6)

1.00

 Lumpectomy

404,612 (52.3)

17,372 (54.1)

0.75 (0.72–0.79)

 Mastectomy

304,812 (39.4)

10,900 (33.9)

0.74 (0.71–0.78)

Chemotherapy

 No/unknown

536,470 (60.7)

27,537 (75.8)

1.00

 Yes

347,411 (39.3)

8776 (24.2)

0.84 (0.81–0.86)

Radiotherapy

 No/unknown

462,215 (52.3)

21,631 (59.6)

1.00

 Yes

421,666 (47.7)

14,682 (40.4)

0.83 (0.82–0.85)

Treatment modesd

 Lumpectomy only

79,295 (10.3)

5149 (16.0)

1.00

 Mastectomy only

138,766 (17.9)

6648 (20.7)

0.88 (0.85–0.92)

 Chemo−/radio-therapy

27,038 (3.5)

1038 (3.2)

1.05 (0.97–1.13)

 Lumpectomy plus chemo−/radio-therapy

325,317 (42.1)

12,223 (38.0)

0.79 (0.76–0.82)

 Mastectomy plus chemo−/radio-therapy

166,046 (21.5)

4252 (13.2)

0.74 (0.71–0.78)

 Otherse

36,829 (4.8)

2817 (8.8)

1.16 (1.10–1.23)

  1. NOTE. Patients with missing information on tumor stage (N = 14,459, 1.57%), tumor grade (N = 97,126, 10.56%), tumor size (N = 52,267, 5.68%), molecular types (N = 24,220, 7.6%) or surgery (N = 3362, 0.4%) were not included in the corresponding analysis
  2. Abbreviations: BCa-1 Breast cancer as the first malignancy, CI Confidence interval, HR Hormone-receptor, HER2 Human epidermal growth factor receptor 2, N Number; OR Odds ratio
  3. a The models were adjusted for age (continuous) and calendar period at diagnosis, race, cohabitation status, percentile of cost of living and high-school education in county of residence
  4. b The models were additionally adjusted for tumor stage, histology, tumor grade, ER status, PR status, and HER2 status
  5. c Information on HER2 status was available from 2010 onward, and thus the analysis was restricted to patients diagnosed thereafter
  6. d Information on surgery and therapy was available from 1998 onward, and thus the analysis was restricted to patients diagnosed thereafter
  7. e Others included surgery (no/unknown), chemotherapy (no/unknown), and radiotherapy (no/unknown)
Back to article page

BMC Cancer

ISSN: 1471-2407

Contact us