Table 3.

Association of patient and tumor characteristics with relapse-free survival and breast cancer–specific survival among 828 hormone receptor–positive patients with complete data for covariates and who received tamoxifen as their sole adjuvant systemic therapy and among 167 patients with hormone receptor–positive tumors with complete data for all the covariates and who received both tamoxifen and chemotherapy as adjuvant systemic therapies^*

	Relapse-free survival		Breast cancer-specific survival
Characteristic and comparison	HR (95% CI)	P value†	HR (95% CI)	P value†
Hormone receptor–positive patients who received only tamoxifen as adjuvant therapy
Total group‡
Age at diagnosis§	0.99 (0.98 to 1.00)	.090	1.00 (0.98 to 1.02)	.95
Grade (3 vs 2 or 1)	1.33 (1.06 to 1.68)	.016	1.35 (1.04 to 1.75)	.023
Tumor size (> 2 vs ≤ 2 cm)	1.56 (1.23 to 1.97)	<.001	1.64 (1.26 to 2.13)	<.001
LVI (positive vs negative)	1.18 (0.91 to 1.51)	.21	1.02 (0.78 to 1.34)	.88
Positive axillary lymph nodes, % of total examined
0–25 vs 0	1.91 (1.40 to 2.61)	<.001	1.69 (1.19 to 2.40)	.004
> 25 vs 0	3.24 (2.38 to 4.42)	<.001	3.26 (2.32 to 4.57)	<.001
Breast cancer subtypes
Luminal B vs luminal A	1.59 (1.25 to 2.03)	<.001	1.60 (1.22 to 2.10)	<.001
Luminal/HER2+ vs luminal A	1.56 (1.09 to 2.25)	.016	1.77 (1.20 to 2.62)	.004
Group with lymph node–negative disease (n = 267)
Age at diagnosis§	1.02 (0.99 to 1.05)	.28	1.03 (1.00 to 1.07)	.06
Grade (3 vs 2 or 1)	1.63 (0.96 to 2.76)	.070	1.25 (0.70 to 2.22)	.45
Tumor size (> 2 vs ≤ 2 cm)	1.42 (0.83 to 2.41)	.20	1.54 (0.85 to 2.78)	.16
LVI (positive vs negative)	0.87 (0.51 to 1.46)	.59	0.90 (0.51 to 1.61)	.73
Breast cancer subtypes
Luminal B vs luminal A	2.14 (1.24 to 3.67)	.006	2.22 (1.22 to 4.04)	.009
Luminal/HER2+ vs luminal A	1.07 (0.36 to 3.16)	.90	1.04 (0.30 to 3.60)	.95
Group with lymph node–positive disease‖
Age at diagnosis§	0.99 (0.97 to 1.00)	.062	1.00 (0.98 to 1.01)	.71
Grade (3 vs 2 or 1)	1.32 (1.02 to 1.70)	.037	1.46 (1.09 to 1.95)	.011
Tumor size (> 2 vs ≤ 2 cm)	1.67 (1.28 to 2.16)	<.001	1.75 (1.30 to 2.34)	<.001
LVI (positive vs negative)	1.33 (0.99 to 1.79)	.057	1.09 (0.80 to 1.51)	.56
Breast cancer subtypes
Luminal B vs luminal A	1.50 (1.14 to 1.97)	.004	1.49 (1.09 to 2.03)	.013
Luminal/HER2+ vs luminal A	1.78 (1.21 to 2.62)	.004	2.03 (1.34 to 3.07)	<.001
Hormone receptor–positive patients who received both tamoxifen and chemotherapy
Total group¶
Age at diagnosis§	0.97 (0.94 to 1.00)	.046	0.98 (0.94 to 1.01)	.13
Grade (3 vs 2 or 1)	1.19 (0.70 to 2.03)	.52	0.94 (0.54 to 1.62)	.82
Tumor size (> 2 vs ≤ 2 cm)	1.00 (0.57 to 1.76)	1.00	1.54 (0.82 to 2.90)	.18
LVI (positive vs negative)	1.05 (0.59 to 1.87)	.86	1.00 (0.54 to 1.84)	.99
% of positive axillary lymph nodes over total examined
0–25 vs 0	1.54 (0.70 to 3.40)	.29	2.11 (0.83 to 5.34)	.12
> 25 vs 0	2.04 (0.96 to 4.30)	.062	3.11 (1.31 to 7.39)	.010
Breast cancer subtypes
Luminal B vs luminal A	2.03 (1.15 to 3.58)	.015	1.92 (1.05 to 3.52)	.034
Luminal–HER2+ vs luminal A	2.65 (1.23 to 5.71)	.013	3.73 (1.70 to 8.16)	.001

^*Multivariable Cox proportional hazards regression analyses were used to estimate the adjusted HRs of breast cancer subtypes. HR = hazard ratio; CI = confidence interval; LVI = lymphovascular invasion.

^†All Wald statistical tests were two-sided.

^‡In the total group, data from 828 patients were available for relapse-free survival and data from 826 patients were available for breast cancer–specific survival.

^§Age is in years.

^‖In this group, data from 561 patients were available for relapse-free survival and data from 559 patients were available for breast cancer–specific survival.

^¶The total group had 167 patients with complete data for all the covariates and who received both tamoxifen and chemotherapy (doxorubicin and cyclophosphamide; fluorouracil, doxorubicin, and cyclophosphamide; or cyclophosphamide, methotrexate, and fluorouracil) as adjuvant systemic therapies. Data from all 167 patients were available for both relapse-free survival and breast cancer–specific survival.