Abstract:
For locally advanced cervical cancer, the standard therapeutic approach involves concomitant chemoradiation therapy, supplemented by a brachytherapy boost. Moreover, an external beam radiotherapy (RT) boost should be considered for treating gross lymph node (LN) volumes. Two boost approaches exist with Volumetric Intensity Modulated Arc Therapy (VMAT): Sequential (SEQ) and Simultaneous Integrated Boost (SIB). This study undertakes a comprehensive dosimetric and radiobiological comparison between these two boost strategies. The study encompassed ten patients who underwent RT for cervical cancer with node-positive disease. Two sets of treatment plans were generated for each patient: SIB-VMAT and SEQ-VMAT. Dosimetric as well as radiobiological parameters including tumour control probability (TCP) and normal tissue complication probability (NTCP) were compared. Both techniques were analyzed for two different levels of LN involvement - only pelvic LNs and pelvic with para-aortic LNs. Statistical analysis was performed using SPSS software version 25.0. SIB-VMAT exhibited superior target coverage, yielding improved doses to the planning target volume (PTV) and gross tumour volume (GTV). Notably, SIB-VMAT plans displayed markedly superior dose conformity. While SEQ-VMAT displayed favorable organ sparing for femoral heads, SIB-VMAT appeared as the more efficient approach for mitigating bladder and bowel doses. TCP was significantly higher with SIB-VMAT, suggesting a higher likelihood of successful tumour control. Conversely, no statistically significant difference in NTCP was observed between the two techniques. This study\'s findings underscore the advantages of SIB-VMAT over SEQ-VMAT in terms of improved target coverage, dose conformity, and tumour control probability. In particular, SIB-VMAT demonstrated potential benefits for cases involving para-aortic nodes. It is concluded that SIB-VMAT should be the preferred approach in all cases of locally advanced cervical cancer.
摘要:
对于局部晚期宫颈癌,标准的治疗方法包括伴随放化疗,辅以近距离放射治疗。此外,对于大体淋巴结(LN)体积的治疗,应考虑加强外束放疗(RT).存在两种具有体积强度调制电弧疗法(VMAT)的增强方法:顺序(SEQ)和同时积分增强(SIB)。本研究对这两种增强策略进行了全面的剂量学和放射生物学比较。该研究包括10例接受RT治疗的宫颈癌淋巴结阳性疾病的患者。为每个患者生成两组治疗计划:SIB-VMAT和SEQ-VMAT。比较了剂量学和放射生物学参数,包括肿瘤控制概率(TCP)和正常组织并发症概率(NTCP)。分析了两种技术的两种不同水平的LN受累-仅骨盆LN和具有主动脉旁LN的骨盆。使用SPSS软件25.0版进行统计学分析。SIB-VMAT表现出优异的目标覆盖率,提高计划目标体积(PTV)和总肿瘤体积(GTV)的剂量。值得注意的是,SIB-VMAT计划显示出明显的剂量一致性。虽然SEQ-VMAT显示出有利于股骨头的器官保留,SIB-VMAT似乎是减轻膀胱和肠剂量的更有效方法。SIB-VMAT的TCP明显更高,表明成功控制肿瘤的可能性更高。相反,两种技术之间的NTCP没有观察到统计学上的显着差异。这项研究的发现强调了SIB-VMAT相对于SEQ-VMAT在改善目标覆盖方面的优势,剂量一致性,和肿瘤控制概率。特别是,SIB-VMAT对涉及主动脉旁淋巴结的病例显示出潜在的益处。结论SIB-VMAT应该是所有局部晚期宫颈癌病例的首选方法。