Table 1.
Demographics of Study 1 (cancers detected at first screen on entry to the PROCAS study) and Study 2 (cancers detected at a subsequent screen or between screening rounds)
| Study 1 | Study 2 | |||||
|---|---|---|---|---|---|---|
| Controls | Cases | p value | Controls | Cases | p value | |
| Number (%) | Number (%) | Number (%) | Number (%) | |||
| Age at consent (years) | 0.9997 | 0.9997 | ||||
| < 50 | 53 (6) | 19 (6) | 46 (5) | 16 (5) | ||
| 50–54 | 242 (26) | 79 (25) | 194 (21) | 64 (20) | ||
| 55–59 | 153 (16) | 52 (16) | 164 (18) | 58 (18) | ||
| 60–64 | 229 (24) | 77 (24) | 286 (31) | 96 (30) | ||
| 65–69 | 196 (21) | 66 (21) | 198 (21) | 68 (21) | ||
| 70+ | 74 (8) | 24 (8) | 47 (5) | 16 (5) | ||
| HRT use | 0.0778 | 0.9320 | ||||
| Unknown | 14 (1) | 9 (3) | 23 (2) | 6 (2) | ||
| Never | 568 (60) | 208 (66) | 475 (51) | 166 (52) | ||
| Previous | 315 (33) | 83 (26) | 332 (36) | 110 (35) | ||
| Current | 50 (5) | 17 (5) | 105 (11) | 36 (11) | ||
| BMI (kg/m2) | 0.9954 | 0.9389 | ||||
| Unknown | 1 (0) | 1 (0) | ||||
| < 25 | 332 (35) | 112 (35) | 335 (36) | 117 (37) | ||
| 25–29 | 331 (35) | 111 (35) | 341 (36) | 113 (36) | ||
| ≥ 30 | 283 (30) | 94 (30) | 259 (28) | 87 (27) | ||
| Menopausal status | 0.4272 | 0.9889 | ||||
| Unknown | 31 (3) | 10 (3) | 32 (3) | 12 (4) | ||
| Premenopausal | 92 (10) | 32 (10) | 67 (7) | 22 (7) | ||
| Perimenopausal | 112 (12) | 38 (12) | 134 (14) | 46 (14) | ||
| Postmenopausal | 712 (75) | 237 (75) | 702 (75) | 238 (75) | ||
| Ethnic origin | 0.1880 | 0.2208 | ||||
| Other/unknown | 52 (5) | 24 (8) | 81 (9) | 35 (11) | ||
| White | 895 (95) | 293 (92) | 854 (91) | 283 (89) | ||
| Parity | 0.7134 | 0.0399 | ||||
| Unknown | 1 (0) | 1 (0) | 4 (1) | |||
| Nulliparous | 112 (12) | 40 (13) | 91 (10) | 44 (14) | ||
| Parous | 834 (88) | 277 (87) | 843 (90) | 270 (85) | ||
| Tyrer-Cuzick (10 year risk, % (median, Q1–Q3)) | 2.74 (2.18–3.58) | 2.94 (2.29–3.88) | 0.0006 | 2.67 (2.09–3.55) | 2.91 (2.24–4.05) | <.0001 |
| Volumetric PD (median, Q1–Q3) | 4.90 (3.63–7.19) | 5.43 (4.06–8.13) | 0.0034 | 4.79 (3.58–7.01) | 5.51 (3.81–7.98) | 0.0044 |
The p values, from likelihood-ratio chi-square tests, indicate whether there are significant difference between cases and controls
HRT hormone replacement therapy, BMI body mass index, Q1 25th percentile, Q3 75th percentile, PD percent density