PGR and breast carcinoma: [13] Luo et al. has reported a 28% increased risk of ER+/PR+ breast cancer in current compared to never smoker, but in contrast to our study and current literature, none with ER+/PR- or ER−/PR-, [7] whereas Gaudet et al. reported association with smoking limited to ER+ breast cancer subtype, and none with ER-, but lacked data on PR status.