Table 5.
Association of risk factors with prolactin receptor expression among 736 women with breast cancer (pre- and post-menopausal) from the Polish Breast Cancer Study
| PRLR staining (negative or low) N (%) | PRLR staining (strong) N (%) | p Value** | |
|---|---|---|---|
| Parity N = 736 | |||
| Nulliparous | 19 (17.8) | 88 (82.8) | |
| Parous | 108 (17.2) | 521 (82.8) | 0.88 |
| Age at first birth* N = 628 | |||
| <20 years | 16 (21.3) | 59 (78.7) | |
| 20–24 | 63 (19.7) | 257 (80.3) | |
| 25–30 | 19 (12.5) | 133 (87.5) | |
| 30+ | 10 (12.4) | 71 (87.7) | 0.03 |
| Number of full-term births* N = 629 | |||
| 1 | 42 (16.2) | 217 (83.8) | |
| 2 | 52 (18.0) | 237 (82.0) | |
| 3+ | 14 (17.3) | 67 (82.7) | 0.69 |
| Age at last birth* N = 629 | |||
| <24 years | 30 (20.3) | 118 (79.7) | |
| 24–27 | 25 (18.4) | 111 (81.6) | |
| 27–31 | 26 (16.2) | 135 (83.9) | |
| 31+ | 27 (14.7) | 157 (85.3) | 0.15 |
| Years since last birth* N = 629 | |||
| <22.5 years | 30 (19.0) | 128 (81.0) | |
| 22.5–31.0 | 28 (19.3) | 117 (80.7) | |
| 31.0–40.0 | 22 (14.0) | 135 (86.0) | |
| 40.0+ | 28 (16.6) | 141 (83.4) | 0.36 |
| Number of months breastfeeding* N = 629 | |||
| Never | 30 (22.1) | 106 (77.9) | |
| <6 months | 46 (13.8) | 287 (86.2) | |
| 6–11 | 17 (18.1) | 77 (81.9) | |
| 12–23 | 15 (22.7) | 51 (77.3) | 0.85 |
| BMI category N = 733 | |||
| <25 | 29 (12.4) | 205 (87.6) | |
| 25 ≤ 30 | 34 (13.4) | 220 (86.6) | |
| 30+ | 62 (25.3) | 183 (74.7) | 0.002 |
Not all strata sum to 100 % due to rounding
*Analyses conducted among only parous women
**p Values from χ 2 test