Toxicity
Overall, treatment-related serious adverse events were less common in the anastrozole group than the tamoxifen group (223 anastrozole vs 369 tamoxifen; OR 0.57, 95% CI 0.48 - 0.69; p<0.0001), but were similar after treatment completion (66 vs 78; OR 0.84, 95% CI 0.60 - 1.19; p=0.3). More fractures were reported during treatment in the anastrozole group than the tamoxifen group (451 vs 351; OR 1.33, 95% CI 1.15 - 1.55; p<0.0001) but were also similar after treatment completion (110 vs 112; OR 0.98, 95% CI 0.74 - 1.30; p=0.9; 10-year rate 2.0% vs 1.5%).r
The 10-year update also confirmed the overall incidence of new primary cancers to be similar in the two treatment groups (13.7% anastrozole vs. 13.9% tamoxifen). While differences in the rates of some new primary cancers were observed, including endometrial, contralateral breast, ovarian, melanoma, lung, colorectal and head and neck cancer, the differences were not statistically significant, with the exception of endometrial cancer, which showed a fourfold increase on tamoxifen; 6 (0.2%) vs. 24 (0.8%), p=0.014.r
Deaths in study populationr
© Lancet Oncol 2010
Adverse eventsr
© Lancet 2005
Cardiovascular, cerebrovascular and thromboembolic events for aromatase inhibitors compared to tamoxifenr
© Cancer Treat Rev 2008