Partial Breast Proton Therapy for Early Stage Breast Cancer

Radiation therapy delivered to the whole breast is standard treatment following tumor removal
for patients with early stage breast cancer. In selected patients, delivering the radiation
treatment to only the part of the breast involved by the tumor may be a viable alternative.
This can decrease the amount of normal tissues exposed to irradiation, potentially decrease
side-effects and shorten the treatment time. Proton beam can decrease the volume of normal
tissues treated compared to standard forms of radiotherapy. This study will recruit patients
with early stage breast cancer following surgical removal to undergo partial breast
radiotherapy with proton beam and determine the recurrence rates and side-effects of
treatment.

Inclusion Criteria:

- Breast carcinoma

- DCIS

- Age 40 years or higher

- Primary tumor 3 cm or less

- Lumpectomy with clip placement

- Axillary node sampling

- Negative margins

Exclusion Criteria:

- Distant metastasis

- Multicentric disease

- Prior radiation or chemotherapy

- Active collagen vascular disease

- Pregnant or lactating

- BRCA mutation

- Lymph nodes with more than microscopic tumor involvement