Real-world overall survival and characteristics of patients with ER-zero and ER-low HER2-negative breast cancer treated as triple-negative breast cancer: a Swedish population-based cohort study.

Survival analysis by ER-status (ER-zero vs ER-low) With respect to overall survival, women with ER-low disease had a borderline significant but not significantly better OS than those with ER-zero disease (HR 0.84, 95% CI 0.71–1.00, p = 0.052) ( Fig. 3 a).

also in 11,409 other papers