The effect of prolonged neoadjuvant endocrine therapy on the efficacy of treatment with breast cancer

Abstract

BACKGROUND: At present, there is no consensus on the required duration of neoadjuvant endocrine therapy (NET), yet there is no consistent conclusion on the factors influencing the efficacy of treatment with breast cancer after prolonged treatment. OBJECTIVE: To explore the effect of prolonged NET on the efficacy of patients with breast cancer and analyze the factors influencing the efficacy of treatment with breast cancer after the treatment duration is prolonged. METHODS: The case histories of 51 patients who were diagnosed with breast cancer and received NET in our hospital from September 2017 to December 2021 were retrospectively analyzed. All patients received NET for over 12 months. The clinical efficacy and tumor size changes after treatment for six months and 12 months were compared, and the factors influencing the efficacy of treatment with breast cancer after patients’ treatment duration was prolonged were analyzed. RESULTS: (1) Among the 51 patients, the objective remission rate (ORR) of NET, at T = 6 months was 21.6%, and the average tumor size was 15.52 ± 7.30 mm. The ORR of the NET at T = 12 months was 52.9%, and the average tumor size was 13.79 ± 7.43 mm. (2) After the treatment duration was prolonged, the clinical ORRs of patients with estrogen receptor (ER) (+) and progesterone receptor (PR) (+) were significantly higher than that of patients with ER (+) and PR (-) and patients with ER (-) and PR (+), which was (P < 0.05). (3) There was no significant difference between the patients’ axillary lymph node status and the Ki67 expression before treatment and the clinical ORR after prolonged treatment, which was (P> 0.05). CONCLUSIONS: (1) Prolonging the NET duration for patients with breast cancer can improve their clinical ORR and further reduce the tumor size, but patients’ conditions should be closely monitored during the treatment process to prevent the progression of disease due to drug resistance. (2) The expression state of ER or PR may be used as a factor influencing the efficacy of treatment with breast cancer after prolonged treatment. (3) There was no significant effect on the patients’ axillary lymph node status and the Ki67 expression before treatment on the clinical efficacy after prolonged treatment.