In addition, we found that ER(+)/PR(-) tumors have the same characteristics, which indicates that even if ER(+)/PR(-) tumors are HER-2 negative, their prognosis is also poor, and the survival prognosis is not as good as that of patients with HER-2(+) tumors, which also supports the hypothesis that PR expression is an independent prognostic factor for breast cancer. The gene discussed is ESR1; the disease is breast cancer.