Prone Breath Hold Technique to Decrease Cardiac and Pulmonary Doses in Women Receiving Left Breast Radiotherapy

Not Applicable

Completed

Brief Summary: This is a pilot study to determine whether the addition of inspiratory hold (breath holding) can decrease the radiation dose that the heart and lung receive for patients being treated for left sided breast cancer.

Detailed Description: Subjects have a standard of care CT simulation, which includes an additional breath hold CT. Inspiratory gated breath-hold will be used. Two radiation plans will be generated: one for the CT scan performed free breathing, and one for the CT scan performed with inspiratory gated breath hold. The cardiac and lung doses will be determined. At the discretion of the treating physician, the plan with the lower cardiac and lung dose may be used to treat the patient.

Recruitment & Eligibility

Inclusion Criteria

Patients of Dr. Gonzalez
≥18 years of age
Node-negative left breast cancer
Invasive or DCIS breast cancer
Prior lumpectomy
Deemed appropriate for treatment in the prone position by the treating physician
Able to tolerate prone position and breath hold during CT simulation

Exclusion Criteria

Arm && Interventions

Group	Intervention	Description
Verify radiation dose to heart and lung	Verify radiation dose to heart and lung	Subjects will undergo the standard of care CT simulation, which includes an additional breath hold CT. Inspiratory gated breath-hold will be used. Two radiation plans will be generated: one for the CT scan performed free breathing, and one for the CT scan performed with inspiratory gated breath hold. The cardiac and lung doses will be determined. At the discretion of the treating physician, the plan with the lower cardiac and lung dose may be used to treat the patient.

Primary Outcome Measures

Name	Time	Method
The Radiation Dose in Gy to the Heart and Lung Using Two Radiation Techniques.	Treatment Day 1 (both pFB and pDIBH scans were done on the same day)	The primary endpoints of this study were to evaluate the feasibility of the combination of prone positioning and RPM pDIPH for breast cancer radiation treatment. Each woman enrolled in the study had 2 radiation plans generated: one for the pFB scan and one for the pDIBH scan. The mean difference between the dosimetrically determined heart, left anterior descending (LAD) artery, and left lung radiation doses were computed with the associated 95% confidence interval; however, the Wilcoxin paired signed rank test was used and listed below as the primary analysis because of the non-normal distributions.

Secondary Outcome Measures

Name	Time	Method
Heart Mean Dose Based on Breast Volume	Treatment Day 1	The breast volume was evaluated using the dose-volume histogram. A paired t-test was used to assess if breast volume and the mean difference for heart was statistically significant. Because paired data were generated the number of women required was less than if 2 independent samples of women were to be used.
Determination of Left Anterior Artery (LAD) Dose Reduction in Women Receiving Prone Breast Radiotherapy When Inspiratory Gating is Added.	Treatment Day 1	This outcome was measured by looking at the maximum dose to the LAD in patients using the free breathing method versus the breath holding method in the prone position. The mean of the maximum doses for each patient was taken and compared using the Wilcoxin Paired Signed Rank Test.
Determination of Cardiac Dose and Lung Dose Reduction in Women Receiving Prone Breast Radiotherapy When Inspiratory Gating is Added.	Treatment Day 1	This outcome was measured by looking at the maximum dose to the heart and maximum dose to the left lung in patients using the free breathing method versus the breath holding method in the prone position. The mean of the maximum doses for each patient was taken and compared using the Wilcoxin Paired Signed Rank Test.