Vaginal estrogen therapy initiation after breast cancer and oncological outcomes: a nationwide population-based target trial emulation.

The article discusses the impact of vaginal estrogen therapy (VET) initiation on disease-free survival (DFS) in women with a history of non-metastatic breast cancer (BC). The study utilized data from the French National Health Data System to emulate target trials and found that VET initiation did not decrease DFS in patients with hormone receptor (HR)-positive tumors treated with tamoxifen. However, VET initiation might decrease DFS in patients treated with aromatase inhibitors, with estriol leading to a more pronounced decrease in DFS than promestriene. The preprint has not been peer-reviewed and provides valuable insights into the potential effects of VET on oncological outcomes in BC patients. [Extracted from the article]