Hypofractionated Radiotherapy After Breast Conserving Surgery

Primary Objectives

To determine the 24-month complication rate of 25Gy in 5 fractions whole radiotherapy +/-
concurrent boost as compared to 40Gy in 15 fraction radiotherapy +/- sequential boost.
Complications will be defined as one or more of the following events: 1) grade 3 or higher
late adverse event, 2) deterioration of cosmesis from excellent/good to fair/poor or from
fair to poor.

ARM 1: Conventional hypofractionation 40 Gy (RBE) / Gy in 15 daily fractions with optional 10
Gy (RBE) / Gy in 4 fractions sequential boost to a total dose of 50 Gy in 19 fractions; or a
concomitant boost to total dose of 48Gy in 15 daily fractions.(n=41)

ARM 2: 5 Fraction Hypofractionation 25 Gy (RBE) / Gy in 5 daily fractions with optional
concurrent boost to a total dose of 30 Gy (RBE) / Gy in 5 fractions (n=41)

Inclusion Criteria:

- Histological confirmation of breast cancer.

- Pathologic Stage T0-T3N0-N1M0.

- ECOG Performance Status (PS) 0 to 2. (Appendix I).

- Able to and provides IRB approved study specific written informed consent.

- Study entry must be within 12 weeks of last surgery (breast or axilla) or last
chemotherapy (if applicable).

- Able to complete all mandatory tests listed in section 4.0.

- Willing to return to enrolling institution for follow-up (during the active monitoring
phase of the study).

- Fair, good or excellent cosmesis, as determined by trained nurse assessment using the
Harvard Cosmetic Scale.

- Radiotherapy must begin within 12 weeks of the last breast cancer surgery or the last
dose of adjuvant chemotherapy.

- Breast conserving surgery and indications for whole breast radiotherapy.

Exclusion Criteria:

- Medical contraindication to receipt of radiotherapy.

- Severe active co-morbid systemic illnesses or other severe concurrent disease which,
in the judgment of the investigator, would make the patient inappropriate for entry
into this study or interfere significantly with the proper assessment of safety and
toxicity of the prescribed regimens.

- Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
arrhythmia, or psychiatric illness/social situations that would limit compliance with
study requirements or providing informed consent.

- Active systemic lupus or scleroderma.

- Pregnancy.

- Prior receipt of ipsilateral breast or chest wall radiation.

- Positive margins on ink after definitive surgery either for DCIS or invasive cancer.

- History of non-breast malignancies (except for in situ cancers treated only by local
excision and basal cell and squamous cell carcinomas of the skin) within 5 years prior
study entry.

- Recurrent breast cancer.

- Indications for comprehensive regional nodal irradiation.