Table 5.
Adjusted odds ratios and 95% confidence interval for the associations between parity and breastfeeding and breast cancer subtypes overall and following re-classification of the luminal A-like subtype by p53 expression
| Subtype | Parous/nulliparous | Parous vs. nulliparous | Ever/never | Ever vs. never breastfed | ||
|---|---|---|---|---|---|---|
| OR (95% CI) | P | OR (95% CI) | P | |||
| A-like (Overall) | 2590/114 | 1.00 (reference) | 2049/320 | 1.00 (reference) | ||
| B-like/HER2− | 959/44 | 0.94 (0.65, 1.35) | 0.75 | 720/127 | 0.89 (0.71, 1.11) | 0.30 |
| B-like/HER2+ | 775/33 | 1.17 (0.78, 1.75) | 0.45 | 594/98 | 1.01 (0.78, 1.29) | 0.96 |
| HER2-enriched | 386/16 | 1.15 (0.67, 1.98) | 0.61 | 319/46 | 1.12 (0.80, 1.57) | 0.50 |
| TNBC | 681/22 | 1.36 (0.85, 2.18) | 0.20 | 518/69 | 1.18 (0.89, 1.57) | 0.24 |
| A-like/p53− | 1152/63 | 1.00 (reference) | 940/153 | 1.00 (reference) | ||
| A-like/p53+ | 858/20 | 2.67 (1.60, 4.51) | <0.01 | 637/80 | 1.38 (1.03, 1.85) | 0.03 |
| B-like/HER2− (overall) | 1.25 (0.83, 1.87) | 0.28 | 0.96 (0.74, 1.24) | 0.74 | ||
| B-like/HER2−/p53− | 295/12 | 1.35 (0.71, 2.57) | 0.35 | 229/35 | 1.08 (0.72, 1.61) | 0.71 |
| B-like/HER2−/p53+ | 415/23 | 1.06 (0.64, 1.75) | 0.81 | 285/58 | 0.85 (0.61, 1.20) | 0.36 |
| B-like/HER2+ (overall) | 1.56 (1.01, 2.43) | 0.04 | 1.09 (0.82, 1.44) | 0.55 | ||
| B-like/HER2+/p53− | 227/12 | 1.30 (0.68, 2.48) | 0.43 | 180/32 | 0.99 (0.65, 1.51) | 0.97 |
| B-like/HER2+/p53+ | 341/16 | 1.37 (0.77, 2.44) | 0.28 | 249/40 | 1.14 (0.78, 1.67) | 0.50 |
| HER2-enriched (overall) | 1.55 (0.88, 2.75) | 0.13 | 1.22 (0.85, 1.75) | 0.28 | ||
| HER2-enriched/p53− | 92/6 | 1.03 (0.42, 2.49) | 0.95 | 83/10 | 1.45 (0.73, 2.89) | 0.29 |
| HER2-enriched/p53+ | 169/8 | 1.32 (0.61, 2.84) | 0.48 | 137/18 | 1.34 (0.79, 2.28) | 0.27 |
| TNBC (overall) | 1.82 (1.10, 3.01) | 0.02 | 1.28 (0.94, 1.74) | 0.12 | ||
| TNBC/p53− | 210/7 | 1.69 (0.75, 3.79) | 0.20 | 164/15 | 1.82 (1.03, 3.20) | 0.04 |
| TNBC/p53+ | 317/8 | 2.39 (1.12, 5.08) | 0.02 | 243/30 | 1.37 (0.90, 2.09) | 0.14 |
| A-like/p53+ | 858/20 | 1.00 (reference) | 637/80 | 1.00 (reference) | ||
| B-like/HER2− (overall) | 0.47 (0.27, 0.80) | <0.01 | 0.69 (0.51, 0.94) | 0.02 | ||
| B-like/HER2−/p53− | 295/12 | 0.50 (0.24, 1.05) | 0.07 | 229/35 | 0.78 (0.51, 1.21) | 0.27 |
| B-like/HER2−/p53+ | 415/23 | 0.39 (0.21, 0.73) | <0.01 | 285/58 | 0.62 (0.43, 0.90) | 0.01 |
| B-like/HER2+ (overall) | 0.58 (0.33, 1.03) | 0.07 | 0.79 (0.57, 1.09) | 0.15 | ||
| B-like/HER2+/p53− | 227/12 | 0.48 (0.23, 1.02) | 0.06 | 180/32 | 0.72 (0.46, 1.13) | 0.16 |
| B-like/HER2+/p53+ | 341/16 | 0.51 (0.26, 1.01) | 0.05 | 249/40 | 0.83 (0.55, 1.26) | 0.38 |
| HER2-enriched (overall) | 0.58 (0.29, 1.14) | 0.11 | 0.88 (0.60, 1.31) | 0.54 | ||
| HER2-enriched/p53− | 92/6 | 0.38 (0.15, 0.99) | 0.05 | 83/10 | 1.06 (0.52, 2.14) | 0.88 |
| HER2-enriched/p53+ | 169/8 | 0.49 (0.21, 1.15) | 0.10 | 137/18 | 0.98 (0.56, 1.79) | 0.93 |
| TNBC (overall) | 0.68 (0.36, 1.26) | 0.22 | 0.93 (0.65, 1.31) | 0.67 | ||
| TNBC/p53− | 210/7 | 0.63 (0.26, 1.53) | 0.31 | 164/15 | 1.32 (0.74, 2.37) | 0.35 |
| TNBC/p53+ | 317/8 | 0.89 (0.38, 2.05) | 0.78 | 243/30 | 0.99 (0.63, 1.57) | 0.99 |
Note: Odds ratios (OR) and 95% confidence intervals (CI) were obtained in multivariate polytomous logistic regression models mutually adjusted for parity or breastfeeding, age, age at menarche, BMI, family history of breast cancer