A Dosimetric Study Comparing Different Radiotherapy Planning Techniques With and Without Deep Inspiratory Breath Hold for Breast Cancer

Abstract

To analyze whether deep inspiratory breath hold (DIBH) would be dosimetrically beneficial irrespective of radiotherapy planning techniques for patients with left breast cancers requiring adjuvant radiotherapy. Methods: Planning CT scans were taken in free-breathing (FB) as well as deep-inspiration breath hold (DIBH) for patients requiring adjuvant radiotherapy for left breast cancers. After registration, three radiotherapy plans -3D-conformal radiotherapy (3DCRT), intensity modulated RT (IMRT), and volumetric modulated arc-therapy (VMAT) -were generated for both FB and DIBH scans for each patient. The dose-volume parameters were collected from the dose-volume histogram and analyzed. A paired t-test is used for statistical analysis of the parameters. Findings: The study was conducted on thirteen patients. The mean dose of the left lung was reduced with DIBH by 32%, 24%, and 6% (8.6 Gy, 6.6 Gy, and 6.4 Gy) with 3DCRT, IMRT, and VMAT, respectively. The mean heart dose was reduced by 3.3 Gy (2.2 vs 5.5 Gy), 2.2 Gy (7.5 vs 9.7 Gy), and 1.2 Gy (5.8 vs 7 Gy) with 3DCRT, IMRT, and VMAT with DIBH. Similarly, the left anterior descending artery (LAD) mean dose was relatively reduced by 80%, 34%, and 20% when compared with the FB scans for 3DCRT, IMRT, and VMAT respectively, with max dose in the 3DCRT plan. Novelty/Applications: DIBH appears to have maximum benefit in achieving a better sparing of organs-at-risk for patients being considered for 3DCRT, and to a lesser extent with even IMRT and VMAT techniques.

Cardiac exposure in left-sided breast cancer patients undergoing deep inspiratory breath hold radiation therapy

“…This study offered information on potential utility of predictors for patients benefiting from DIBH. We studied some similar research ( 29 , 30 ). The investigation of comparing those parameters from FB and DIBH scans in some patients worthy of further study.…”

Cardiac segments dosimetric benefit from deep inspiration breath hold technique for left-sided breast cancer radiotherapy

“…Numerous studies have shown that the DIBH technique allows for heart preservation during the RT of the left breast, reducing the MHD by 26.2-75.0% compared to standard free-breathing (FB) and leaving the absolute MHD between 0.7-5.0 Gy [6,7]. The use of modern RT techniques with dose intensity modulation of the beam (IMRT) combined with DIBH can achieve even greater reductions in MHD [8]. Left lung dose reductions have also been observed with the DIBH technique [6,7].…”