APBI Proton Feasibility and Phase II Study

Inclusion Criteria

• Histologically confirmed diagnosis of invasive or non-invasive breast cancer.
• Invasive ductal, medullary, papillary, colloid (mucinous) or tubular histologies.
• AJCC T1 or T2; N0 or N1mic; Stage IA-IIA breast cancer or AJCC TIS (Stage 0) ductal carcinoma in situ without invasion
• Gross disease must be unifocal with pathologic (invasive and/or DCIS) tumor size 3 cm or less. (Patients with microscopic multifocality are eligible as long as total pathological size is 3 cm or less).
• Estrogen and/or progesterone receptor positive invasive breast cancer. DCIS stage 0 does not require receptor testing.
• No evidence of distant metastatic disease as documented by history and physical examination (radiographic staging only to be performed as indicated by symptoms or physical findings.)
• Patients must have an ECOG Performance Status of 0, 1 or 2
• Age ≥ 50.
• Patients must be able to provide informed consent.
• Patients must have undergone breast-conserving surgery
• All tumors (invasive and non-invasive disease) must be excised with a minimum margin width of ≥ 2 mm. Re-excision of surgical margins is permitted. Focally close ( 3cm), T3, T4, Node positive (other than N1mi), or M1 disease
• Lobular or mixed ductal and lobular histology.
• Multifocal primary tumor.
• Clear delineation of the extent of the lumpectomy cavity is not possible. Prior or simultaneous malignancies within the past two years (other than carcinoma in situ of the cervix, CIS of the colon, melanoma in situ, thyroid cancer, and basal cell or squamous cell carcinoma of the skin).
• Any non-axillary sentinel node(s) positive. (Note that intramammary nodes are staged as axillary nodes).
• Patients who have had a positive SLNB but decline completion ALND are not eligible.
• Patients treated with neoadjuvant chemotherapy are not eligible.
• Palpable or radiographically suspicious ipsilateral or contralateral axillary, supraclavicular, infraclavicular, or internal mammary nodes, unless there is histological confirmation that these nodes are negative for tumor.
• Suspicious microcalcifications, densities, or palpable abnormalities (in the inpsilateral or contralateral breast) unless these were biopsied and found to be benign.
• Proven multicentric carcinoma (invasive cancer or DCIS) in more than one quadrant or two or more breast cancers not resectable through a single lumpectomy incision.
• Paget's disease of the nipple.
• Surgical margins that cannot be microscopically assessed or are positive at pathological evaluation. A focally positive margin determined to be at an anatomic boundary of resection by the surgeon, such as posterior fascia for posterior margins and skin for anterior margins, is also acceptable. If surgical margins are rendered free of disease by re-excision, the patient is eligible.
• Breast implants. (Patients who have implants removed are eligible).
• Prior ipsilateral breast or thoracic radiation for any condition.
• Collagen vascular disease, specifically dermatomyositis with a CPK level above normal or with an active skin rash, systemic lupus erythematosis, or scleroderma.
• Pregnant women, women planning to become pregnant and women that are nursing.
• Psychiatric or addictive disorders or other conditions that, in the opinion of the investigator, would preclude the patient from meeting the study requirements.
• Actively being treated on any other therapeutic research study.