- In patients with early-stage breast cancer, extended adjuvant therapy with aromatase inhibitors (AIs) significantly improved disease-free survival (DFS), especially for contralateral breast cancer recurrence.
- No significant differences were observed in overall survival (OS), distant metastatic recurrence, locoregional recurrence, and grade ≥3 adverse events.
Why this matters
- The data on the effects of extended AI therapy in early-stage breast cancer are limited and inconclusive.
- Meta-analysis of 7 randomized clinical trials including 16,926 patients with early-stage breast cancer identified after a search on PubMed, EmBase, and the Cochrane library until March 2018.
- Patients were randomly assigned to either extended adjuvant therapy with AIs or control group (shorter AIs, placebo, or observation).
- Funding: National Key R&D Program of China.
- Extended AIs were not associated with significant improvement in OS (6 studies; HR, 0.95; P=.488)
- DFS was significantly prolonged in patients on extended AIs vs control group (7 studies; HR, 0.75; P<.001>
- Extended AIs significantly reduced the risk for contralateral breast cancer recurrence (relative risk [RR], 0.46; P<.001>
- No significant difference was observed in distant metastatic recurrence (RR, 0.80; P=.055) and locoregional recurrence (RR, 0.76; P=.127) between groups.
- No significant difference was observed in grade ≥3 adverse events.
- Moderate heterogeneity for DFS.