Baehr Andrea, Schäfer Sebastian, Jäckel Maria, Becker Saskia Alexandra, Ghandili Susanne, Grohmann Maximilian, Eich Hans Theodor, Oertel Michael
Department of Radiation Oncology, University Hospital of Hamburg-Eppendorf, 20246 Hamburg, Germany.
Department of Radiation Oncology, University Hospital Leipzig, 04103 Leipzig, Germany.
Cancers (Basel). 2024 Dec 22;16(24):4265. doi: 10.3390/cancers16244265.
Primary mediastinal B-cell lymphoma (PMBCL) is a rare form of aggressive B-cell lymphoma with a predominant onset in young patients. The minimization of potential (late) side effects is of cardinal interest for these patients. An anticipation of the individual risk profile is desirable to counsel the patient on the putative impact of radiotherapy (RT). RT plans for a cohort of 25 patients with PMBCL were prospectively designed. One plan with two parallel- opposing fields (APPA) and another with volume-modulated arc therapy (VMAT) technique with 40 Gy in 2 Gy fractions each. Normal The normal tissue complication probability (NTCP) was calculated using the Lyman--Kutcher--Burman model for heart, lung and oesophageal toxicity. APPA planning resulted in lower median doses (Dmedian) for the heart and lungs, whereas all other dose metrics for heart, lungs and esophagus were lower in VMAT planning. A significant difference in the mean NTCPs when comparing the APPA to VMAT plans was seen for increased cardiac mortality, pneumonitis and esophagitis. PTV size correlated with increased cardiac mortality and esophagitis in both plan variations and with pneumonitis for VMAT plans. Dmean, Dmedian, and V20Gy correlated with the risk for pneumonitis, and Dmean, Dmedian, and V1% with the risk for esophagitis in both variants. We showed decreased risk of different NTCPs for VMAT and APPA planning for thoracic toxicities. The use of an IMRT technique like VMAT showed advantages for several DVH metrics in organs at risk and should therefore be recommended for radiation treatment of PMBCL.
原发性纵隔B细胞淋巴瘤（PMBCL）是侵袭性B细胞淋巴瘤的一种罕见形式，主要发病于年轻患者。将潜在（晚期）副作用降至最低对这些患者至关重要。预先了解个体风险状况有助于就放射治疗（RT）的假定影响向患者提供咨询。前瞻性地设计了25例PMBCL患者的放疗计划。一个计划采用两个平行相对野（APPA），另一个计划采用容积调强弧形治疗（VMAT）技术，每次分割剂量为2 Gy，总剂量40 Gy。使用Lyman-Kutcher-Burman模型计算心脏、肺和食管毒性的正常组织并发症概率（NTCP）。APPA计划导致心脏和肺部的中位剂量（Dmedian）较低，而VMAT计划中心脏、肺部和食管的所有其他剂量指标较低。比较APPA和VMAT计划时，在心脏死亡率增加、肺炎和食管炎方面，平均NTCPs存在显著差异。在两种计划变体中，PTV大小与心脏死亡率增加和食管炎相关，在VMAT计划中与肺炎相关。在两种变体中，Dmean、Dmedian和V20Gy与肺炎风险相关，Dmean、Dmedian和V1%与食管炎风险相关。我们发现VMAT和APPA计划在胸部毒性方面不同NTCPs的风险降低。使用如VMAT这样的调强放疗技术在危及器官的多个剂量体积直方图指标上显示出优势，因此应推荐用于PMBCL的放射治疗。
