Fig. 2.

The LTED score predicts early tumor response to aromatase inhibitors. A) Forty-eight patients with ER+ breast cancer were treated with neoadjuvant letrozole for 2 weeks (cohort MILLER48). Ki67 scoring was performed on pre- and post-treatment (2 weeks) tumor biopsies. B-C) The LTED score for patient tumors from (A) was calculated from pretreatment (B) and post-treatment (C) biopsies. LTED scores were compared to the Ki67 scores at 2 weeks. Data were analyzed by linear regression with adjustment for tumor microarray batch effect. D) Sixty-nine patients with ER+ breast cancer were treated with neoadjuvant anastrozole for 14 days (cohort SMITH69). Ki67 scoring was performed on pre- and post-treatment tumor biopsies. E-F) Pretreatment (E) and post-treatment (F) LTED scores were calculated for tumors from (D) and compared to the 2-week Ki67 scores as in (B-C).