A phase II clinical trial designed to test the effect of combining endocrinal therapy (Letrozole) with chemotherapy (Capecitabine) in first line treatment of advanced cases of female breast cancer with ER positive disease.

This is a randomized clinical trial that assigns patients with female breast cancer in the metastatic entity or advanced -beyond local disease treatment - entity into two arms. Arm A contains Letrozole with metronomic Capecitabine versus arm B that contains Letrozole alone. This is to be applied on ER positive HER2 negative tumours.

Inclusion Criteria:

• Female sex
• Age 18-70
• ECOG-PS 0-II.
• Histopathological proof of breast cancer
• ER positive (Allred score of ≥3 out of 8), and HER2 negative by IHC (or ISH if HER2 +2).
• Metastatic/recurrent disease as proven by CT scan, bone scan or clinical examination (for skin lesions). Biopsy of the recurrent lesions is encouraged but not mandatory.
• Either hormone sensitive setting (Denovo metastatic disease or disease progression after more than 1 year of ending adjuvant endocrine therapy) or secondary resistance to tamoxifen therapy (disease relapse after more than 2 years of starting and less than 1 year of ending adjuvant endocrine therapy, or DP of metastatic disease after more than 6 months of first line tamoxifen).
• Adequate organ function.
• Signed informed consent

Exclusion criteria:

• Inadequate organ functions.
• Disease progression while on prior aromatase inhibitor therapy.
• Primary endocrine resistance.
• Double primary cancer (history of other malignancy apart from a non melanoma skin cancer).
• Refusal to sign consent.