Dose-Volume Analysis of Lung and Heart according to Respiration in Breast Cancer Patients Treated with Breast Conserving Surgery

Abstract

PurposeAdjuvant radiotherapy of breast cancer using a photon tangential field incurs a risk of late heart and lung toxicity. The use of free breathing (FB), expiration breath hold (EBH), and deep inspiration breath hold (DIBH) during tangential breast radiotherapy as a means of reducing irradiated lung and heart volume was evaluated.MethodsIn 10 women with left-sided breast cancer (mean age, 44 years) post-operative computed tomography (CT) scanning was done under different respiratory conditions using FB, EBH, and DIBH in 3 CT scans. For each scan, an optimized radiotherapy plan was designed with 6 MV photon tangential fields encompassing the clinical target volume after breast-conserving surgery.ResultsThe results of dose-volume histograms were compared using three breathing pattern techniques for the irradiated volume and dose to the heart. A significant reduction dose to the irradiated heart volume for the DIBH breathing technique was compared to FB and EBH breathing techniques (p<0.05).ConclusionThis study demonstrated that the irradiated heart volume can be significantly reduced in patients with left-sided breast cancer using the DIBH breathing technique for tangential radiotherapy.

Deep inspiration breath-hold technique for left-sided breast cancer: An analysis of predictors for organ-at-risk sparing

“…Several other groups also showed significant cardiac sparing, but they did not find any lung sparing. 19,20 Shim et al 20 reported a nonsignificant reduction in lung V 20 and a trend for improved mean lung dose with DIBH, but the relative increase in lung volume with DIBH was much smaller in their study, approximately 45%, compared with 75% in our study, which may have limited their ability to detect any lung sparing. Our data suggest that accompanying a larger total lung volume, there is a significant reduction in mean lung dose and lung V 20 with DIBH.…”

“…14,15,[19][20][21]23,24 Direct comparisons of these studies are challenging because of the differences in reported dose-volume histogram parameters, treatment delivery techniques, inclusion of PMRT patients, and use of RNI. Swanson et al 14 published one of the largest series of patients and showed significant reductions in the mean heart dose, HVIF, heart V 5-30 , mean lung dose, and lung V 5-20 with DIBH.…”

“…14,15,[19][20][21] Although these benefits of the DIBH technique have been clearly demonstrated in the previous literature, there are limited data evaluating appropriate patient selection for this technique. We posed the question whether this approach would benefit patients being treated to different targets, including intact breast and chest wall Ϯ regional nodes, and whether specific anatomic criteria could be identified that might independently predict for cardiac sparing.…”

Quantification of variation in dose–volume parameters for the heart, pericardium and left ventricular myocardium during thoracic tumor radiotherapy

“…To address this question, ECG-gated 4DCT based on breath-hold was used in this study to analyze the impacts of cardiac activity on the heart and substructures. Shim et al found that the mean value of the heart D 5 was reduced from 15.33 Gy to 5.26 Gy and that V 18 was reduced from 4.50 to 1.83 with breath-hold treatment compared with free-breathing treatment for breast cancer radiotherapy [ 18 ]. In addition, we employed MIM, a commercial software package used in clinical practice, and the algorithm of deformation image registration has been proven to have high accuracy [ 22 ].…”

Preliminary toxicity results using partial breast 3D-CRT with once daily hypo-fractionation and deep inspiratory breath hold

“…HIP merged two types of radiation therapy in a novel way by offering “Canadian” hypo-fractionation (15–20 daily fractions) with a partial breast volume. Deep inspiration breath-hold (DIBH) was employed to reduce cardiac dose [ 22 – 24 ] and improve target volume coverage by immobilizing the breast and decreasing toxicity to the ipsilateral lung [ 25 ].…”