To further validate the algorithm described above (Fig. 2) to cluster the tumor patient samples based on ESR1 expression and EERES to select hormonal therapy-treated patients with better responsiveness, we examined 12 patients from MD Anderson with low-grade serous ovarian cancer (LGSOC), who were treated with standard chemotherapy followed by maintenance hormonal therapy [32]. The gene discussed is ESR1; the disease is ovarian serous adenocarcinoma.