Association between mammographic density and basal-like and luminal A breast cancer subtypes

Breast Cancer Research

Table 2 Odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer risk by tumor subtype associated with BI-RADS-measured mammographic density

	Number of subjects		Cases versus controls			Triple-negatives versus controls
	Controls	Cases	Model 1^a	Model 2^b	TN cases, n	Model 1	Model 2
			OR (95% CI)	OR (95% CI)		OR (95% CI)	OR (95% CI)
Almost entirely fat	25	13	1.00 (Referent)	0.48 (0.22, 1.08)	1	1.00 (Referent)	0.17 (0.02, 1.43)
Scattered fibroglandular densities	197	183	2.07 (0.93, 4.59)	1.00 (Referent)	31	5.96 (0.70, 50.64)	1.00 (Referent)
Heterogeneously dense	253	232	2.06 (0.92, 4.60)	1.00 (0.7, 1.35)	40	5.83 (0.68, 50.04)	0.98 (0.5, -1.75)
Extremely dense	53	63	2.45 (0.99, 6.09)	1.19 (0.72, 1.95)	12	7.13 (0.74, 68.90)	1.20 (0.49, 2.90)
			P_trend = 0.24^c			P_trend = 0.31
			Basal-like versus controls			Luminal A versus controls
	BL cases, n		Model 1	Model 2	LA cases, n	Model 1	Model 2
			OR (95% CI)	OR (95% CI)		OR (95% CI)	OR (95% CI)
Almost entirely fat	1		1.00 (Referent)	0.29 (0.03, 2.51)	4	1.00 (Referent)	0.49 (0.15, 1.59)
Scattered fibroglandular densities	19		3.45 (0.40, 29.90)	1.00 (Referent)	69	2.03 (0.63, 6.59)	1.00 (Referent)
Heterogeneously dense	22		3.03 (0.34, 26.67)	0.88 (0.43, 1.80)	86	2.09 (0.64, 6.79)	1.03 (0.68, 1.56)
Extremely dense	6		3.58 (0.34, 37.97)	1.04 (0.34, 3.17)	22	1.98 (0.54, 7.34)	0.98 (0.50, 1.92)
			P_trend = 0.67			P_trend = 0.60

^aModel 1 is adjusted for age, race, body mass index, menopausal status, family history of breast cancer, age at menarche, use of hormone therapy, and parity and age at first full-term pregnancy combined, where BI-RADS category 1 (almost entirely fat) is the referent group; ^bModel 2 is adjusted for the same variables as Model 1 but BI-RADS category 2 (scattered fibroglandular densities) is the referent group; ^cP-value for trend test is based on the likelihood ratio test statistic and is two-sided. The same ordinal model was fit to assess the P-value for trend of Model 1 and Model 2. BI-RADS, Breast Imaging Reporting and Data System; TN, triple-negative; BL, basal-like; LA, luminal-A; n, number of subjects.

ISSN: 1465-542X