Research

Hormonal

The highest breast cancer risk was seen in cancers positive for estrogen receptor (ER+) and progesterone receptor (PR+).

Understanding receptor status may help in assessing breast cancer risk in patients using unopposed estrogen.

GoodSupportsmedium confidence
The highest risk seen in cancers positive for estrogen receptor (ER+) and progesterone receptor (PR+).
Wendy Y. Chen et al. · Archives of Internal Medicine · 2006

Why this rating

Based on a prospective cohort study design.

Source

Unopposed Estrogen Therapy and the Risk of Invasive Breast Cancer

Wendy Y. Chen et al. · Archives of Internal Medicine · 2006

DOI 10.1001/archinte.166.9.1027

cohort · n=28835Cited 249×
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DOI resolved against Crossref · corpus check 2026-06-10

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