Mohanty Samarpita, Patil Divya, Joshi Kishore, Gamre Poonam, Mishra Ajay, Khairnar Sunil, Kakoti Sangeeta, Nayak Lingaraj, Punatar Sachin, Jain Jeevanshu, Phurailatpam Reena, Goda Jayant S
Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai 410210, India.
Department of Hemato Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai 410210, India.
Cancers (Basel). 2024 Feb 6;16(4):690. doi: 10.3390/cancers16040690.
Hodgkin lymphomas are radiosensitive and curable tumors that often involve the mediastinum. However, the application of radiation therapy to the mediastinum is associated with late effects including cardiac and pulmonary toxicities and secondary cancers. The adoption of conformal IMRT and deep inspiration breath- hold (DIBH) can reduce the dose to healthy normal tissues (lungs, heart and breast). We compared the dosimetry of organs at risk (OARs) using different IMRT techniques for two breathing conditions, i.e., deep inspiration breath hold (DIBH) and free breathing. Twenty-three patients with early-stage mediastinal Hodgkin lymphomas were accrued in the prospective study. The patients were given treatment plans which utilized full arc volumetric modulated arc therapy (F-VMAT), Butterfly VMAT (B-VMAT), and fixed field IMRT (FF-IMRT) techniques for both DIBH and free breathing methods, respectively. All the plans were optimized to deliver 95% of the prescription dose which was 25.2 Gy to 95% of the PTV volume. The mean dose and standard error of the mean for each OAR, conformity index (CI), and homogeneity index (HI) for the target using the three planning techniques were calculated and compared using Student's -test for parametric data and Wilcoxon signed-rank test for non-parametric data. The HI and CI of the target was not compromised using the DIBH technique for mediastinal lymphomas. The mean values of CI and HI for both DIBH and FB were comparable. The mean heart doses were reduced by 2.1 Gy, 2.54 Gy, and 2.38 Gy in DIBH compared to FB for the F-VMAT, B-VMAT, and IMRT techniques, respectively. There was a significant reduction in V5Gy, V10Gy, and V15Gy to the heart ( < 0.005) with DIBH. DIBH reduced the mean dose to the total lung by 1.19 Gy, 1.47 Gy, and 1.3 Gy, respectively. Among the 14 female patients, there was a reduction in the mean right breast dose with DIBH compared to FB (4.47 Gy vs. 3.63 Gy, = 0.004). DIBH results in lower heart, lung, and breast doses than free breathing in mediastinal Hodgkin Lymphoma. Among the different IMRT techniques, FF-IMRT, B-VMAT, and F-VMAT showed similar PTV coverage, with similar conformity and homogeneity indices. However, the time taken for FF-IMRT was much longer than for the F-VMAT and B-VMAT techniques for both breathing methods. B-VMAT and F-VMAT emerged as the optimal planning techniques able to achieve the best target coverage and lower doses to the OARs, with less time required to deliver the prescribed dose.
霍奇金淋巴瘤是对放疗敏感且可治愈的肿瘤,常累及纵隔。然而,对纵隔进行放射治疗会带来包括心脏和肺部毒性以及继发性癌症在内的晚期效应。采用适形调强放射治疗(IMRT)和深吸气屏气(DIBH)可降低对健康正常组织(肺、心脏和乳腺)的剂量。我们比较了在两种呼吸状态下,即深吸气屏气(DIBH)和自由呼吸时,使用不同IMRT技术对危及器官(OARs)的剂量测定。23例早期纵隔霍奇金淋巴瘤患者纳入了这项前瞻性研究。分别为患者制定了治疗计划,在DIBH和自由呼吸方法中,分别采用全弧容积调强弧形治疗(F-VMAT)、蝶形VMAT(B-VMAT)和固定野IMRT(FF-IMRT)技术。所有计划均进行优化,以将95%的处方剂量(25.2 Gy)给予95%的计划靶体积(PTV)。计算并比较了使用三种计划技术时每个OAR的平均剂量和平均标准误差、靶区的适形指数(CI)和均匀性指数(HI),对于参数数据使用学生t检验,对于非参数数据使用威尔科克森符号秩检验。对于纵隔淋巴瘤,使用DIBH技术时靶区的HI和CI不受影响。DIBH和自由呼吸时CI和HI的平均值具有可比性。与自由呼吸相比,在DIBH状态下,F-VMAT、B-VMAT和IMRT技术的平均心脏剂量分别降低了2.1 Gy、2.54 Gy和2.38 Gy。DIBH状态下心脏的V5Gy、V10Gy和V15Gy有显著降低(P<0.005)。DIBH分别使全肺平均剂量降低了1.19 Gy、1.47 Gy和1.3 Gy。在14名女性患者中,与自由呼吸相比,DIBH状态下右乳腺平均剂量降低(4.47 Gy对3.63 Gy,P = )。在纵隔霍奇金淋巴瘤中,DIBH状态下心脏、肺和乳腺的剂量低于自由呼吸时。在不同的IMRT技术中,FF-IMRT、B-VMAT和F-VMAT显示出相似的PTV覆盖情况,适形和均匀性指数相似。然而,对于两种呼吸方法,FF-IMRT所需时间比F-VMAT和B-VMAT技术长得多。B-VMAT和F-VMAT成为能够实现最佳靶区覆盖且对OARs剂量更低、输送处方剂量所需时间更少的最佳计划技术。 (原文中“4.47 Gy vs. 3.63 Gy, = 0.004”处“ = ”后面缺少具体比较对象,翻译时保留原文格式)