Table 2.
Adjusted HRs of Subsequent IBC Classified by Laterality and Hormone Receptor Status According to Race and Ethnicity in Women With DCIS in SEER, 1990‐2015
| Person‐y | All Second Invasive Eventsa | ER+ or PR+ | ER– and PR– | |||||
|---|---|---|---|---|---|---|---|---|
| Cases, No. | HRb (95% CI) | Cases, No. | HRb (95% CI) | Cases, No. | HRb (95% CI) | |||
| Subsequent IBCc | White | 1,018,475 | 5884 | 1.00 | 4653 | 1.00 | 821 | 1.00 |
| Black | 129,931 | 1002 | 1.42 (1.32‐1.52) | 720 | 1.31 (1.21‐1.43) | 190 | 1.86 (1.57‐2.20) | |
| Asian | 128,657 | 807 | 1.08 (0.99‐1.17) | 620 | 1.01 (0.92‐1.11) | 135 | 1.40 (1.14‐1.71) | |
| Hispanic | 102,614 | 640 | 1.09 (1.00‐1.18) | 505 | 1.09 (0.99‐1.20) | 102 | 1.24 (1.00‐1.54) | |
| P heterogeneity = .0004 | ||||||||
| Ipsilateral IBCd | White | 709,275 | 2438 | 1.00 | 1846 | 1.00 | 393 | 1.00 |
| Black | 89,081 | 478 | 1.65 (1.49‐1.83) | 341 | 1.58 (1.40‐1.78) | 86 | 1.83 (1.43‐2.35) | |
| Asian | 86,294 | 378 | 1.23 (1.09‐1.38) | 286 | 1.19 (1.03‐1.36) | 61 | 1.34 (0.99‐1.81) | |
| Hispanic | 72,785 | 309 | 1.19 (1.05‐1.35) | 235 | 1.20 (1.04‐1.38) | 59 | 1.40 (1.05‐1.87) | |
| P heterogeneity = .57 | ||||||||
| Contralateral IBCe | White | 971,003 | 3134 | 1.00 | 2556 | 1.00 | 363 | 1.00 |
| Black | 126,291 | 446 | 1.18 (1.07‐1.31) | 322 | 1.07 (0.95‐1.20) | 92 | 1.97 (1.55‐2.52) | |
| Asian | 125,104 | 396 | 0.97 (0.86‐1.10) | 306 | 0.89 (0.78‐1.02) | 68 | 1.61 (1.20‐2.16) | |
| Hispanic | 98,900 | 292 | 0.98 (0.87‐1.11) | 234 | 0.97 (0.84‐1.11) | 38 | 1.13 (0.80‐1.60) | |
| P heterogeneity < .0001 | ||||||||
Abbreviations: CI, confidence interval; DCIS, ductal carcinoma in situ; ER, estrogen receptor; IBC, invasive breast cancer; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.
Second IBCs included those positive for ER or PR (ER+ or PR+), those negative for both ER and PR (ER–PR–), and those with no information on ER and PR.
HRs were adjusted for the following: age (20‐39, 40‐49, 50‐59, 60‐69, or ≥70 years) and year of the primary DCIS diagnosis (1990‐1999, 2000‐2009, or 2010‐2015); registry; treatment for primary DCIS (no surgical treatment, breast‐conserving surgery alone, breast‐conserving surgery followed by radiation therapy, mastectomy, or unknown); and histopathological features of primary DCIS, including the tumor size (<2 cm, 2‐5 cm, ≥5 cm, or unknown), grade (well differentiated, moderately differentiated, poorly differentiated, or unknown), histology (comedo, papillary, cribriform, solid, or not otherwise specified), and hormone receptor expression (positive, negative, or unknown).
Subsequent IBCs included ipsilateral IBCs, contralateral IBCs, and subsequent metastatic breast cancers.
The analysis included the patients who had been treated with breast‐conserving surgery or no surgical treatment for their primary DCIS.
Patients who had undergone bilateral mastectomy for their primary DCIS were excluded.