ESR1 and neoplasm: As shown in Fig. 2, highly significant correlations (P < 0.0001 for all markers) were observed for ER (tumor R = 0.76), Ki‐67 (tumor R = 0.41), CD4 (tumor R = 0.34, stroma R = 0.52), and CD8 (tumor R = 0.48, stroma R = 0.56).