Efficacy of Neoadjuvant Endocrine Therapy Compared to Chemotherapy in Breast Cancer Patients

Efficacy of Endocrine Therapy Compared to Chemotherapy as a Neoadjuvant Treatment for Patients With Hormone Receptor-positive and HER2-negative Breast Cancer.

Eligible patients will be divided into two groups; one will receive neoadjuvant endocrine therapy and the other one will receive neoadjuvant chemotherapy.

Patients will be randomized into two groups:

The first group (Arm A) will receive NCT; (Any approved Chemotherapy protocol by guidelines.

The second group(Arm B) will receive NET; GnRH analog Goserelin acetate 3.6 mg every 4 weeks with tamoxifen 20 mg daily for premenopausal patients or an aromatase inhibitor for postmenopausal patients.

• Before and during treatments (every 3 weeks for the NCT group, and every 4 weeks for the NET group), the clinical assessment will be performed for all patients.
• All patients will undergo breast magnetic resonance imaging (MRI) before the start of treatment, after 12 weeks (3 months) of treatment, and after the end of treatment before surgery.
• We will determine the objective tumor response with every measurement method and assess the response according to the Response Evaluation Criteria in Solid Tumor (RECIST) version 1.1.
• Treatment will be continued for 19-21 weeks before surgery for the chemotherapy group and 24 weeks for the endocrine therapy group.
• Ki-67 will be assessed using a sample of the core biopsy before treatment and a surgery specimen after treatment.
• Adverse events will be recorded at every patient visit and will be assessed according to the Common Terminology Criteria for Adverse Events Version 5.0.
• Surgery will be performed between the 24th and 26th week.
• Arm B Patients who will develop PD or SD after 6 months of treatment will be shifted to arm A.

The primary endpoint will be;

• The clinical response rate at the end of neoadjuvant treatment, as will be determined using caliper and MRI measurements.
• A clinical response included either a complete response (CR), a partial response (PR), Progressive Disease (PD), or Stable Disease (SD) according to the (RECIST) version 1.1.

Secondary endpoints will be;

• The rate of pathological complete response (pCR).
• The rate of breast conservation surgery.
• Ki-67 changes.
• The length of time to maximum response within a treatment period.
• The Adverse events associated with each treatment arm.

Inclusion Criteria:

• Any histological type of invasive breast cancer. All grades of breast cancer (I, II, III). ER-positive and/or PR-positive, HER2-negative breast cancer. ER and/or PR level of positivity ≥34 % (score 4 according to modified Allred score).

Clinical Stages: any T N1-3, or T2-4 any N, M0.

Exclusion Criteria:

• Hormone receptor positivity < 34%. inflammatory breast cancer Metastatic breast cancer. Recurrent breast cancer. Other malignancy. Unfit patients for chemotherapy.