The current study is a prospective phase II study; Eligible patients will receive hypofractionated Irradiation at a total dose of 28.5Gy in 5 once-weekly fractions of 5.7Gy in 5 weeks to the Whole Breast or chest wall with or without peripheral lymphatic irradiation.

Testing the feasibility of a hypofractionated adjuvant radiotherapy regimen after breast surgery on a-once-weekly basis for a total dose of 28.5Gy in 5 fractions over 5 weeks in Kasr EL Aini Hospital.

Inclusion Criteria:

1. Histologically proven diagnosis of invasive breast adenocarcinoma.
2. Prior radical surgery (Modified Radical Mastectomy or Breast Conservative Surgery).
3. No macroscopic evidence of distant metastases at diagnosis.

Exclusion Criteria:

1. Prior radiation to the thoracic region.
2. Pregnancy.
3. Patients with synchronous or prior malignancy.
4. Positive surgical margins.