This phase II trial studies how well hypofractionated radiation therapy works in treating participants with breast cancer before surgery. 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.
PRIMARY OBJECTIVES: I. To determine the pathologic complete response (pCR) rate after hypofractionated radiotherapy to the whole breast alone, based on the postsurgical specimen. SECONDARY OBJECTIVES: I. To evaluate acute and late toxicity with preoperative radiation including grade \>= 2 pneumonitis. II. To estimate the 5-year locoregional control, distant recurrence, invasive disease-free survival, cause-specific survival, and overall survival. CORRELATIVE AND EXPLORATORY OBJECTIVES: I. To evaluate patient-reported outcomes. II. To evaluate clinical features, treatment technique, dose-volume parameters, histologic and genetic variants associated with adverse events, and fair and poor cosmetic outcomes or unplanned surgical intervention. III. Evaluate tumor mutation signatures before and after radiation; correlate tumor mutation signatures before and after radiation with pathologic information at the time of surgery. IV. To describe the pathologic changes seen in breast cancer patients with preoperative radiation. OUTLINE: Participants undergo hypofractionated radiation therapy daily for 5 days, then undergo standard of care surgery 4-16 weeks after radiation therapy. After completion of study treatment, participants are followed up at 12 weeks, 6, 12, 24, and 36 months, and 5 years after radiation therapy.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
TREATMENT
Masking
NONE
Enrollment
25
Undergo hypofractionated radiation therapy
Mayo Clinic in Arizona
Scottsdale, Arizona, United States
Mayo Clinic in Florida
Jacksonville, Florida, United States
Mayo Clinic
Rochester, Minnesota, United States
Pathologic Complete Response (pCR) Rate Defined as a Residual Tumor Burden of 0-1 in the Surgical Specimen
The proportion of successes (number of patients achieving pCR at time of definitive surgery) will be estimated by the number of successes divided by the total number of evaluable patients. Confidence intervals for the true success proportion will be calculated according to the approach of Duffy and Santner.
Time frame: up to 2 years
Number of Participants With Acute Adverse Events (AE)
The maximum grade for each type of acute AE will be recorded for each patient. Data will be summarized as frequencies and relative frequencies. Additionally, the relationship of the adverse event(s) to the study treatment will be taken into consideration.
Time frame: Up to 180 days post radiation therapy
Incidence of Late Adverse Events
The maximum grade for each type of late AE will be recorded for each patient. Data will be summarized as frequencies and relative frequencies by treatment arm. Additionally, the relationship of the adverse event(s) to the study treatment will be taken into consideration.
Time frame: Up to 5 years post radiation therapy
Locoregional Control
The cumulative incidence of locoregional recurrence will be estimated using a competing risks method (Gooley et al.). The competing risks will be distant breast cancer recurrence and death.
Time frame: Up to 5 years
Invasive Disease-free Survival
Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% confidence intervals (CIs).
Time frame: From registration until the time of disease recurrence or death due to any cause, assessed up to 5 years
Distant Recurrence
Time frame: Up to 5 years
Disease- Free Survival
Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% CIs.
Time frame: From registration until the time of disease recurrence or death due to any cause, assessed up to 5 years
Cause-specific Survival
Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% CIs.
Time frame: From registration to death due to breast cancer assessed up to 5 years
Overall Survival
Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% CIs.
Time frame: From registration to death due to any cause assessed up to 5 years
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.