Hypofractionation And Ultra-Hypofractionation In Adjuvant Radiotherapy For Breast Cancer

Comparative Study Between Hypofractionation And Ultra-Hypofractionation In Adjuvant Radiotherapy For Breast Cancer

Prospective randomized study comparing 5 fractions in alternative days to standard 15 fractions regarding effectiveness and feasibility during adjuvant treatment in breast caner patients aged above 50 years

In Alexandria, the number of working linear machines are limited with overcrowded waiting list which lead to prolongation of overall treatment time and delay in starting radiotherapy. Providing the available data, Principle investigator is conducting this study in parallel with fast forward protocol to provide an alternative cost effective approach to patients.

The rationale behind hypofractionation depends mainly on the alpha beta ratio (α/β) and the overall treatment time. In Breast cancer the ratio is around 4 which is slightly lower than other tumors such as head and neck. The lower the ratio the higher the dose per fraction is needed to compensate slower proliferating tumors. Also, the overall treatment time could affect the local recurrence of breast cancer which is increased with long duration of treatment.

This study will include at least 100 patients with non metastatic histologically proved breast cancer who are indicated for adjuvant radiotherapy.

The patients will be randomized into two arms:

• Control arm: will include 50 patients who will receive standard 40.05 Gray (2.67 Gy/fx) over 15 fractions with or without boost over 3 weeks biologically effective dose (BED) for early and late effect equal 50.74.Gy10 and 75.69 Gy3 respectively.
• Experimental arm: will include 50 patients who will receive 26 Gray (5.2 Gy/fx) over 5 fractions over 1.5 weeks with BED for early and late effect equal 39.52 Gy10 and 71.07 Gy3 respectively

Inclusion Criteria:

• Age ≥50 years old.
• Informed consent.
• Either breast conservative surgery or mastectomy.
• Invasive breast cancer with p T1-3, p N0-2.
• Non metastatic breast cancer proven by clinical examinations and imaging (X-ray chest and ultrasound or CT scan chest and abdomen).

Exclusion Criteria:

• Evidence of distant metastases.
• Prior irradiation.
• Inflammatory breast cancer.
• Tumor with T4 (skin nodules or fixed to chest wall or ulceration).
• Tumor with positive margins.