| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | |
|---|---|---|---|---|---|
| Assumed risk: RT+ | Corresponding risk: RT− | ||||
| Overall survival - T stage: 1 (12 year follow-up) | 12 yr OS 85% | 12 yr OS 77% (73% to 81%) |
HR 1.59 (1.29 to 1.96) |
263 (1 study) | Moderate1 |
| Overall survival - N stage: 0 (5 to 12 year follow-up) | 5 yr OS 88% | 5 yr OS 85% (83% to 87%) |
HR 1.29 (1.12 to 1.5) |
1154 (3 studies) | Moderate2 |
| Overall survival - Margins: negative (5 to 12 year follow-up) | 5 yr OS 88% | 5 yr OS 85% (83% to 87%) |
HR 1.29 (1.12 to 1.5) |
1154 (3 studies) | Moderate2 |
| Overall survival - Age: 65+ (5 to 10 year follow-up) | 5 yr OS 88% | 5 yr OS 87% (85% to 90%) |
HR 1.06 (0.87 to 1.3) |
891 (2 studies) | High |
|
Overall survival - Adjuvant systemic therapy: none (20 year follow-up) | 20 yr OS 50% | 20 yr OS 47% (37% to 56%) |
HR 1.1 (0.85 to 1.42) |
381 (1 study) | Moderate3 |
| Local recurrence - T stage: 1 (10 to 12 year follow-up) | 90% free from local recurrence at 10 yrs | 75% free from local recurrence at 10 yrs (66% to 82%) |
HR 2.7 (1.84 to 3.97) |
1378 (2 studies) | Moderate3 |
| Local recurrence - N stage: 0 (5 to 12 year follow-up) | 96% free from local recurrence at 5 yrs | 88% free from local recurrence at 5 yrs (83% to 91%) |
HR 3.22 (2.31 to 4.49) |
3340 (4 studies) | Moderate3 |
| Local recurrence - Margins: negative (5 to 12 year follow-up) | 96% free from local recurrence at 5 yrs | 88% free from local recurrence at 5 yrs (83% to 91%) |
HR 3.22 (2.31 to 4.49) |
3340 (4 studies) | Moderate3 |
| Local recurrence - Age: 65+ (5 to 10 year follow-up) | 99% free from local recurrence at 5 yrs | 95% free from local recurrence at 5 yrs (90% to 97%) |
HR 5.35 (2.78 to 10.29) |
1962 (2 studies) | Low1 |
| Treatment-related morbidity – fractures (cause unspecified; all patients N stage 0, 65+, negative margins; 5 year follow-up) | 106 per 1000 | 116 per 1000 (50 to 272) |
RR 1.10 (0.47 to 2.57) | 171 (1 study) | Low4 |
| Treatment-related morbidity - congestive cardiac failure (all patients N stage 0, 65+, negative margins; 5 year follow-up) | 35 per 1000 |
35 per 1000 (7 to 168) |
RR 0.99 (0.21 to 4.76) |
171 (1 study) | Low6 |
| Treatment-related morbidity - myocardial infarction (all patients N stage 0, 65+, negative margins; 5 year follow-up) | 71 per 1000 |
58 per 1000 (18 to 184) |
RR 0.82 (0.26 to 2.6) |
171 (1 study) | Low4 |
| Treatment-related morbidity - secondary cancer (cause unspecified; all patients N stage 0, 65+, negative margins; 5 year follow-up) | 35 per 1000 | 89 per 1000 (8 to 928) |
RR 2.53 (0.24 to 26.51) |
1497 (2 studies) | Low1 |
| Treatment-related morbidity - score 10+ on HADS depression scale (all patients N stage 0, 65+, negative margins; 5 year follow-up) | 10 per 1000 |
30 per 1000 (3 to 281) |
RR 3.12 (0.33 to 29.49) |
206 (1 study) | Low4 |
| Treatment-related morbidity - score 10+ on HADS anxiety scale (all patients N stage 0, 65+, negative margins; 5 year follow-up) | 86 per 1000 |
119 per 1000 (52 to 270) |
RR 1.39 (0.61 to 3.15) |
206 (1 study) | Low4 |
| HRQoL - EQ5D scale (all patients N stage 0, 65+, negative margins; 5 year follow-up) |
The mean HRQoL – EQ5D scale (all patients N stage 0, 65+, negative margins) in the intervention groups was 0.02 lower (0.1 lower to 0.06 higher) |
168 (1 study) | Low5 | ||
| HRQoL - reduction in scores on Breast Cancer Chemotherapy Questionnaire (all patients N stage 0, negative margins; 2 month follow-up) | 270 per 1000 |
160 per 1000 (119 to 214) |
RR 0.59 (0.44 to 0.79) | 720 (1 study) | Not possible to GRADE this outcome due to study included from previous guideline |
Rates of overall survival and local recurrence in the control group correspond to the weighted average across included trials or the trial with the shortest follow-up period where these differ across included trials
CI: Confidence interval; EQ5D, EuroQol Research Foundation measure of general health status; HADS: Hospital Anxiety and Depression Scale; HR: Hazard ratio; HRQoL: Health related quality of life; OS: overall survival; RR: Risk ratio;
<300 events
Random effects model with significant heterogeneity - I squared value 74% - not possible to investigate heterogeneity as additional subgroups of interest identified by the GC were not reported for the trials that contributed to this estimate. All estimated effects were in the same direction
Total events <300
<300 events and 95% CI crosses both thresholds for minimally important difference based on GRADE default values (0.80 and 1.25)
N<400
total events<300; not downgraded based on 95% CI due to very small differences in absolute risk
From: Evidence reviews for breast radiotherapy
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