Nagpal Puneet, Pruthi Deep Shankar, Shanmugam Prabakar, Pandey Manish Bhushan, Singh Harpreet
Department of Radiation Oncology, Action Cancer Hospital, New Delhi, India.
J Cancer Res Ther. 2023 Apr-Jun;19(3):573-578. doi: 10.4103/jcrt.jcrt_50_21.
Radiation therapy to left breast cancer patients results in significant exposure to heart resulting in long-term cardiac morbidity. This exposure can be reduced by performing deep inspiratory breath-hold (DIBH) technique, however, patient selection criteria or predictive parameters are not routinely used which can identify patients who will have significant benefit with this technique. This study intends to find and use these predictive parameters measured on free-breathing (FB) simulation scan which can help to select such patients so as to develop our institutional protocol.
A total of 35 patients of left breast cancer postsurgery were recruited in the study. All patients underwent 2-3 sessions of DIBH coaching followed by planning computed tomography scan in both FB phase and DIBH phase. Various anatomical parameters such as cardiac contact distance parasagittal (CCDps), CCD axial, heart-chest distance (HCD), and D were measured on FB scan and were correlated with a mean heart dose achieved in DIBH scan.
Dose to normal structures, namely heart and lung, was drastically reduced for DIBH scan over FB scan. V5, V10, and V20 of heart also followed a similar reduction. The mean dose to heart in FB scan was 5.34 Gy, while in DIBH scan, it was 2.79 Gy which was statistically significant. Among all the parameters measured, CCDps and D had a statistically significant positive correlation with the mean heart dose in DIBH phase while HCD had a negative correlation which was statistically significant.
Cardiac parameters on FB scan such as CCDps, HCD, and D predict the patients with usual cardiac risk who will benefit most with DIBH techniques setting an arbitrarily cutoff value.
对左乳癌患者进行放射治疗会使心脏受到大量辐射，从而导致长期心脏疾病。然而，通过采用深吸气屏气（DIBH）技术可以减少这种辐射，但目前尚未常规使用患者选择标准或预测参数来识别能从该技术中显著获益的患者。本研究旨在寻找并使用在自由呼吸（FB）模拟扫描中测量的这些预测参数，以帮助选择此类患者，从而制定我们机构的方案。
本研究共招募了35例左乳癌术后患者。所有患者均接受2 - 3次DIBH指导，随后在FB期和DIBH期进行计划计算机断层扫描。在FB扫描中测量了各种解剖参数，如矢状旁心脏接触距离（CCDps）、CCD轴向、心脏 - 胸部距离（HCD）和D，并将其与DIBH扫描中获得的平均心脏剂量进行关联。
与FB扫描相比，DIBH扫描时心脏和肺等正常结构的剂量大幅降低。心脏的V5、V10和V20也有类似程度的降低。FB扫描中心脏的平均剂量为5.34 Gy，而在DIBH扫描中为2.79 Gy，具有统计学意义。在所有测量参数中，CCDps和D与DIBH期的平均心脏剂量具有统计学意义的正相关，而HCD具有统计学意义的负相关。
FB扫描中的心脏参数，如CCDps、HCD和D，可预测通常具有心脏风险的患者，这些患者将从DIBH技术中获益最大，并设定了一个任意的截止值。
