Hypofractionated Partial Breast Irradiation in Treating Patients With Early Stage Breast Cancer

Optimizing Preventative Adjuvant Linac-Based Radiation: The OPAL Trial a Phase II/III Study of Hypofractionated Partial Breast Irradiation in Women With Early Stage Breast Cancer

This phase II trial studies how well hypofractionated partial breast irradiation works in treating patients with early stage breast cancer. Hypofractionated radiation therapy delivers higher doses of radiation therapy over a shorter period of time and may kill more tumor cells and have fewer side effects. Treating only the part of the breast where the cancer started may lead to fewer side effects than standard treatment.

PRIMARY OBJECTIVE:

I. The risk of grade 2 or higher toxicity occurring during radiation and through the 6 month post-radiation follow up visit in patients treated with Optimizing Preventative Adjuvant Linac-based Radiation (OPAL) regimen.

SECONDARY OBJECTIVES:

I. To measure patient-reported cosmetic outcome, functional status, and breast pain with the OPAL regimen at 6 months, one year, two years, three years, four years, and five years after completing the OPAL regimen.

II. To measure physician-reported and photographically-assessed cosmetic outcome at 6 months, one year, two years, three years, four years, and five years after completing the OPAL regimen and to compare this to the best performing arm of 2010-0559.

III. To determine the 5-year risk of pathologically-confirmed invasive and/or in situ ipsilateral breast tumor recurrence (IBTR) for patients with ductal breast carcinoma in situ (DCIS) and early invasive breast cancer.

IV. To determine the 5-year risk of any recurrence of breast cancer, disease-free survival, and overall survival.

V. To determine maximal late (within 5 years) toxicities using the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version (v) 4.0 scale.

VI. To establish the feasibility of conducting multi-center radiation therapy trials within the MD Anderson Network.

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM I: Patients undergo hypofractionated partial breast irradiation daily for 5 days. Patients may then receive 3 additional boost fractions at the discretion of the doctor.

ARM II: Patients undergo standard breast irradiation daily for 15 days. Patients may then receive 5 additional boost fractions at the discretion of the doctor.

After completion of study treatment, patients are followed up at 6 months, and at 1.5, 3.5, and 5.5 years.

Inclusion Criteria:

• Diagnosis of pathologically-confirmed invasive breast cancer or ductal carcinoma in situ
• Pathologic T stage of Tis, T1, or T2 with total size of tumor =< 3 cm (this size criteria applies to both pure DCIS and invasive tumors)
• For patients with invasive breast cancer, pathologic N stage of N0, N0 (i-), or N0 (i+); pathologic staging of the axilla is not required for patients with pure DCIS
• Treatment with breast conserving surgery
• Unifocal primary tumor based on imaging and clinical assessment; microscopic multifocality is allowed
• Final surgical margins negative defined as no tumor on ink; lobular carcinoma in situ involving the final surgical margin will be disregarded
• For invasive cancers, the tumor must be estrogen receptor positive (defined as 10% or greater expression of estrogen receptor)
• If the patient has a history of a prior non-breast cancer, all treatment for this cancer must have been completed at least one month prior to study registration and the patient must have no evidence of disease for this prior non-breast cancer
• Patients must be enrolled on the trial within 12 weeks of the later of two dates: the final breast conserving surgical procedure or administration of the last cycle of cytotoxic chemotherapy
• Final criteria for eligibility established after simulation: The tumor bed can be readily visualized on simulation computed tomography (CT) and is localized to one quadrant or region of the breast that is amenable to partial breast irradiation

Exclusion Criteria:

• Tumor invasion of the skin including dermis, chest wall, or pectoralis musculature
• Any evidence of nodal positivity beyond pathologic stage of pN0(i+)
• Systemic chemotherapy prior to final breast conserving surgery
• Patient is pregnant or nursing
• History of therapeutic irradiation to the breast, lower neck, mediastinum or other area in which there could potentially be overlap with the affected breast
• History of prior invasive or in situ cancer in either breast
• Current diagnosis of bilateral breast cancer
• History of lupus or scleroderma