DIBH Improves Lung, Liver Parameters in Patients With Breast Cancer

In Clinical Studies News by Barbara Jacoby

By: Conference Insider

From: oncnet.com

Regular deep inspiratory breath-hold (DIBH) can help improve lung and liver parameters in patients who have right breast cancer (rBC) with regional node irritation (RNI), according to a study presented by Gabrielle W. Peters, Yale School of Medicine, New Haven, CT, at the National Comprehensive Cancer Network Virtual Annual Congress.

“While DIBH is routinely utilized for left-sided breast cancers, its benefits for rBC have yet to be established. We compared free-breathing (FB) and DIBH treatment plans for a cohort of rBC undergoing RNI to determine its potential benefits,” wrote Dr Peters and colleagues.

From October 2017 to May 2020, patients with rBC considered for RNI were included in the analysis, with each being given FB v.s. DIBH plans. Dr Peters and her team used dose-volume histograms to evaluate the parameters of mean lung dose, ipsilateral lung V 20 /V 5 (volumes of lung receiving 20 Gy and 5 Gy, respectively); mean heart dose and heart V 5 (volumes of heart receiving 5 Gy); liver V 20 absolute /V 30 absolute (absolute volume of liver receiving 20 Gy and 30 Gy, respectively), liver D max, and total liver volume irradiated (TVI liver). Researchers used Wilcoxon signed-rank testing to compare dosimetric parameters.

This study is the largest cohort study to date, analyzing DBHI for RNI-rBC in 54 eligible patients, with 108 FB and DIBH plan to compare. Results show that DIBH significantly decreased all lung and liver parameters: mean lung dose decreased from 19.7 GY with FB to 16.2 Gy with DIBH, lung V 20 went from 40.7% to 31.7%, and lung V 5 from 61.2% to 54.5%(all <.001), respectively. Meanwhile, TV liver decreased from 1446cc with FB to 1264cc with DIBH (= .006), liver D max went from 50.2 Gy to 48.9 Gy (= .023), liver V 20 decreased to 23.99cc from 78.8cc (<.001), and liver V30 from 58.1cc to 14.6cc (= .067), respectively.

Although there was no significant improvement in heart parameters, the V 5Heart decreased from 1.25 with FB to 0.6 with DIBH (= .067).

“Our findings demonstrate significant improvement in all lung and liver parameters with DIBH, supporting its routine use for rBC pts being considered for comprehensive RNI. This study suggests that DIBH should be strongly considered in routine clinical practice for RNI-rBH to reduce lung and liver doses,” concluded Dr Peters et al.

Peters GW, Gao SJ, Knowlton C, et al. Benefit of Deep Inspiratory Breath Hold for Right Breast Cancer When Regional Lymph Nodes Are Irradiated. Presented at: the NCCN 2021 Virtual Annual Conference; March 18-20,2021; Virtual. Abstract CLO21-025.