Table 3.
New breast events and 10-year estimates of percentages with an event in patients according to radiotherapy randomisation
| Randomised to radiotherapy (n=522) | Randomised to no radiotherapy (n=508) | Hazard ratio (95% CI) | p value | ||
|---|---|---|---|---|---|
| All patients | |||||
| Ipsilateral | 40 (7·1%) | 105 (19·4%) | 0·32 (0·22–0·47) | <0·0001 | |
| Invasive | 19 (3·3%) | 50 (9·1%) | 0·32 (0·19–0·56) | <0·0001 | |
| DCIS | 21 (3·8%) | 51 (9·7%) | 0·38 (0·22–0·63) | <0·0001 | |
| Unknown | 0 | 4 | .. | .. | |
| Contralateral | 18 (3·3%) | 21 (4·1%) | 0·84 (0·45–1·58) | 0·6 | |
| Invasive | 11 (2·1%) | 12 (2·8%) | 0·90 (0·40–2·05) | 0·8 | |
| DCIS | 4 (0·6%) | 9 (1·4%) | 0·43 (0·13–1·41) | 0·2 | |
| Unknown | 3 | 0 | .. | .. | |
| All invasive | 31 (5·6%) | 62 (10·1%) | 0·46 (0·30–0·72) | 0·001 | |
| All DCIS | 26 (4·0%) | 63 (11·6%) | 0·38 (0·24–0·60) | <0·0001 | |
| All unknown* | 3 | 4 | .. | .. | |
| All new breast events | 60 (10·6%) | 129 (23·2%) | 0·41 (0·30–0·56) | <0·0001 | |
| Patients not receiving tamoxifen (n=475) | |||||
| Ipsilateral | 21 (4·0%) | 59 (11·6%) | 0·31 (0·18–0·52) | <0·0001 | |
| Invasive | 9 (1·3%) | 28 (4·9%) | 0·24 (0·11–0·55) | 0·001 | |
| DCIS | 12 (2·3%) | 29 (5·4%) | 0·41 (0·21–0·81) | 0·01 | |
| Unknown | 0 | 2 | .. | .. | |
| Contralateral | 9 (1·7%) | 13 (2·8%) | 0·68 (0·29–1·59) | 0·4 | |
| Invasive | 5 (1·0%) | 7 (1·0%) | 0·71 (0·22–2·23) | 0·6 | |
| DCIS | 2 (0·4%) | 6 (1·0%) | 0·33 (0·10–1·61) | 0·2 | |
| Unknown | 2 | 0 | .. | .. | |
| All unknown† | 2 | 0 | .. | .. | |
| All new breast events | 32 (6·0%) | 72 (13·1%) | 0·41 (0·30–0·57) | <0·0001 | |
| Patients receiving tamoxifen (n=555) | |||||
| Ipsilateral | 19 (3·4%) | 46 (8·7%) | 0·37 (0·22–0·64) | <0·0001 | |
| Invasive | 10 (1·9%) | 22 (4·1%) | 0·44 (0·21–0·93) | 0·03 | |
| DCIS | 9 (1·5%) | 22 (4·3%) | 0·35 (0·16–0·78) | 0·01 | |
| Unknown | 0 | 2 | .. | .. | |
| Contralateral | 9 (1·5%) | 8 (1·4%) | 1·10 (0·43–2·86) | 0·8 | |
| Invasive | 6 (1·1%) | 5 (1·0%) | 1·17 (0·36–3·84) | 0·8 | |
| DCIS | 2 (0·2%) | 3 (0·4%) | 0·66 (0·11–3·96) | 0·7 | |
| Unknown | 1 | 0 | .. | .. | |
| All unknown† | 1 | 5 | .. | .. | |
| All new breast events | 28 (5·4%) | 59 (11·7%) | 0·44 (0·32–0·60) | <0·0001 | |
Data are number (%). DCIS=ductal carcinoma in situ.
*
Laterality or invasive unknown.
†
Laterality unknown.