Trial Outcomes & Findings for Hypofractionated Radiation Therapy in Treating Participants With Breast Cancer Before Surgery (NCT NCT03624478)

Results Overview

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.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

25 participants

Primary outcome timeframe

up to 2 years

Results posted on

2026-05-15

Participant Flow

Participant milestones

Participant milestones
Measure	Treatment (Hypofractionated Radiation Therapy) Participants undergo hypofractionated radiation therapy daily for 5 days, then undergo standard of care surgery 4-16 weeks after radiation therapy.\>\> \>\> Hypofractionated Radiation Therapy: Undergo hypofractionated radiation therapy
Overall Study STARTED	25
Overall Study COMPLETED	24
Overall Study NOT COMPLETED	1

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Hypofractionated Radiation Therapy in Treating Participants With Breast Cancer Before Surgery

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Treatment (Hypofractionated Radiation Therapy) n=24 Participants Participants undergo hypofractionated radiation therapy daily for 5 days, then undergo standard of care surgery 4-16 weeks after radiation therapy.\>\> \>\> Hypofractionated Radiation Therapy: Undergo hypofractionated radiation therapy
Age, Continuous	63.9 years STANDARD_DEVIATION 8.4 • n=11 Participants
Sex: Female, Male Female	24 Participants n=11 Participants
Sex: Female, Male Male	0 Participants n=11 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=11 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	23 Participants n=11 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=11 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=11 Participants
Race (NIH/OMB) Asian	2 Participants n=11 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=11 Participants
Race (NIH/OMB) Black or African American	1 Participants n=11 Participants
Race (NIH/OMB) White	21 Participants n=11 Participants
Race (NIH/OMB) More than one race	0 Participants n=11 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=11 Participants
Enrollment Site Arizona	16 Participants n=11 Participants
Enrollment Site Florida	8 Participants n=11 Participants
Method of Payment Medicare	9 Participants n=11 Participants
Method of Payment Private Insurance	15 Participants n=11 Participants

PRIMARY outcome

Timeframe: up to 2 years

Population: If more than the target number of 22 patients are accrued, the additional patients will not be used to evaluate the stopping rule or used in any decision making process.

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.

Outcome measures

Outcome measures
Measure	Treatment (Hypofractionated Radiation Therapy) n=22 Participants Participants undergo hypofractionated radiation therapy daily for 5 days, then undergo standard of care surgery 4-16 weeks after radiation therapy. \>\> \>\> Hypofractionated Radiation Therapy: Undergo hypofractionated radiation therapy
Pathologic Complete Response (pCR) Rate Defined as a Residual Tumor Burden of 0-1 in the Surgical Specimen	0.64 proportion of participants

SECONDARY outcome

Timeframe: Up to 180 days post radiation therapy

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.

Outcome measures

Outcome measures
Measure	Treatment (Hypofractionated Radiation Therapy) n=24 Participants Participants undergo hypofractionated radiation therapy daily for 5 days, then undergo standard of care surgery 4-16 weeks after radiation therapy. \>\> \>\> Hypofractionated Radiation Therapy: Undergo hypofractionated radiation therapy
Number of Participants With Acute Adverse Events (AE) Any Grade 2+ AE · No	16 Participants
Number of Participants With Acute Adverse Events (AE) Any Grade 2+ AE · Yes	8 Participants
Number of Participants With Acute Adverse Events (AE) Any Grade 3+ AE · No	19 Participants
Number of Participants With Acute Adverse Events (AE) Any Grade 3+ AE · Yes	5 Participants

SECONDARY outcome

Timeframe: Up to 5 years post radiation therapy

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.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to 5 years

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.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: From registration until the time of disease recurrence or death due to any cause, assessed up to 5 years

Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% confidence intervals (CIs).

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to 5 years

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: From registration until the time of disease recurrence or death due to any cause, assessed up to 5 years

Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% CIs.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: From registration to death due to breast cancer assessed up to 5 years

Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% CIs.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: From registration to death due to any cause assessed up to 5 years

Will be estimated with a Kaplan-Meier estimator and curve. Estimates will be given for specific time points along with 95% CIs.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to 5 years

The subscales of the Breast Cancer Treatment Outcomes Scale (BCTOS), elements from Patient Reported Outcomes Version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), and other patient reported measures such as fatigue, breast pain, breast shape, and arm related morbidity outlined in the appendix will be summarized as the mean +/- SD and median (minimum value, maximum value). Scale score trajectories over time will be examined using stream plots and mean plots with standard deviation error bars overall. Analysis will include percent change from baseline using t-tests and generalized linear models to test for changes at each time point and non-zero slope respectfully.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Baseline up to 5 years

Assessed using a modified Harvard Cosmesis Scale and the BCTOS. The values of the cosmesis instruments (patient self-reported and panel-assessed) will be summarized with the frequencies and confidence intervals of fair or poor cosmesis events.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Baseline up to 2 years

Cosmesis will be assessed by a panel of breast cancer medical providers using digital photographs.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to 5 years

Associated with adverse events, and fair and poor cosmetic outcomes or unplanned surgical intervention.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to 5 years

Will be analyzed before and after radiotherapy as compared to pathologic information at the time of surgery. Continuous variable will be compared using unpaired t tests and nominal variables will be compared using contingency tables and Chi square analyses.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to 5 years

Will be described.

Outcome measures

Outcome data not reported

Adverse Events

Treatment (Hypofractionated Radiation Therapy)

Serious events: 2 serious events

Other events: 22 other events

Deaths: 2 deaths

Serious adverse events

Serious adverse events
Measure	Treatment (Hypofractionated Radiation Therapy) n=24 participants at risk Hypofractionated Radiation Therapy: Undergo hypofractionated radiation therapy
General disorders Death NOS	4.2% 1/24 • Number of events 1 • up to 3 years
Respiratory, thoracic and mediastinal disorders Resp, thoracic, mediastinal - Oth spec	4.2% 1/24 • Number of events 1 • up to 3 years

Other adverse events

Other adverse events
Measure	Treatment (Hypofractionated Radiation Therapy) n=24 participants at risk Hypofractionated Radiation Therapy: Undergo hypofractionated radiation therapy
Musculoskeletal and connective tissue disorders Superficial soft tissue fibrosis	29.2% 7/24 • Number of events 17 • up to 3 years
Respiratory, thoracic and mediastinal disorders Aspiration	4.2% 1/24 • Number of events 1 • up to 3 years
Skin and subcutaneous tissue disorders Pruritus	4.2% 1/24 • Number of events 1 • up to 3 years
Skin and subcutaneous tissue disorders Skin hyperpigmentation	45.8% 11/24 • Number of events 22 • up to 3 years
Skin and subcutaneous tissue disorders Skin hypopigmentation	8.3% 2/24 • Number of events 2 • up to 3 years
Vascular disorders Lymphedema	33.3% 8/24 • Number of events 17 • up to 3 years
General disorders Pain	70.8% 17/24 • Number of events 39 • up to 3 years
Injury, poisoning and procedural complications Dermatitis radiation	50.0% 12/24 • Number of events 16 • up to 3 years
Injury, poisoning and procedural complications Seroma	12.5% 3/24 • Number of events 4 • up to 3 years
Metabolism and nutrition disorders Hyponatremia	4.2% 1/24 • Number of events 1 • up to 3 years
Musculoskeletal and connective tissue disorders Fibrosis deep connective tissue	16.7% 4/24 • Number of events 9 • up to 3 years

Additional Information

Dr. Carlos Vargas

Mayo Clinic

Phone: 480-342-1267

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place