Nasopharyngeal carcinoma (NPC) is rather common in Southeast Asia and Southern China. The standard treatment for NPC is intensity-modulated radiotherapy (IMRT). A large number of the NPC survivors benefit from the IMRT, while some suffer from the late toxicities which can be life-threatening or significantly erode the patients’ quality of life and functional status, especially in the locally advanced NPC. Nowadays the late radiotherapy-related toxicities have been the most important concern for the radiotherapists and patients, who look forward to the better long-term tumor local control and overall survival. Therefore, we carried out a review about the late radiotherapy-related toxicities of the vital organs at risk after IMRT for NPC patients.
Objective To investigate the relationships between circulating tumor cells (CTCs), circulating tumor endothelial cells (CTECs) and treatment methods in patients with nasopharyngeal carcinoma (NPC) at different stages of treatment. Methods The data of NPC patients at different treatment periods in West China Hospital of Sichuan University from March 2016 to November 2019 were retrospectively collected. The patients received CTCs test and part of those patients received CTECs test, by subtraction enrichment-immunostaining-fluorescence in situ hybridization. The relationships of CTCs and CTECs with radiotherapy and chemotherapy, and the correlations between CTCs and CTECs in NPC patients were analyzed. Results A total of 191 patients were included. Among them, there were 66 cases before initial treatment, 38 cases after induction chemotherapy, and 87 cases after concurrent chemoradiotherapy. A total of 127 patients received CTECs test, including 41 cases before initial treatment, 29 cases after induction chemotherapy, and 57 cases after concurrent chemoradiotherapy. The positive rates of CTCs were 89.4%, 81.6% and 69.0% respectively in the three stages of treatment, and the difference was statistically significant only between the pre-treatment group and the post-concurrent chemoradiotherapy group (P=0.003). The number of CTCs in the post-concurrent chemoradiotherapy group was lower than that in the pre-treatment group and the post-induction chemotherapy group (P<0.001, P=0.002). The number of triploid CTCs in the post-concurrent chemoradiotherapy group was significantly different from that in the pre-treatment group and the post-induction chemotherapy group (P=0.009, P=0.013). The number of tetraploid CTCs in the post-concurrent chemoradiotherapy group was significantly different from that in the post-induction chemotherapy group (P=0.007). The number of polyploidy (pentaploid or > 5 copies of chromosome 8) CTCs in the post-concurrent chemoradiotherapy group was significantly different from that in the pre-treatment group (P<0.001). The positive rates of CTECs were 70.7%, 82.8% and 64.9% respectively in the three stages of treatment, and the difference was not statistically significant (P>0.05). The number of CTECs in the post-concurrent chemoradiotherapy group was only lower than that in the post-induction chemotherapy group (P=0.009). There was no significant difference in the number of triploid or tetraploid CTECs among the three groups (P=0.265, P=0.088). The number of polyploid CTECs was statistically different only between the post-concurrent chemoradiotherapy group and the post-induction chemotherapy group (P=0.007). Spearman correlation analysis showed that there was a significant positive correlation between CTCs and CTECs (rs=0.437, P<0.001). Conclusions Concurrent chemoradiotherapy plays a decisive role in reducing the number of CTCs in the blood of NPC patients, while induction chemotherapy does not appear to directly cause changes in the number of CTCs. In NPC patients, different types of CTCs have different responses to different treatments. There is a significant positive correlation between CTECs level and CTCs level in NPC.
【摘要】 目的 研究Monaco治疗计划系统中不同参数设置对容积旋转调强放射治疗(VMAT)计划质量的影响，得出更合理的治疗计划参数设置以提高VMAT治疗质量。 方法 2010年1-5月间治疗3例患者，为食管癌、宫颈癌和鼻咽癌各1例，分别设置不同的计划参数进行容积旋转调强计划优化，通过多种评估指标比较各VMAT计划质量的差异，得出临床所需的MSC、MSS、SSF、Sm、MMS和MDR共6个治疗计划参数对VMAT治疗质量的影响。 结果 MSC、MSS和SSF的3个参数对VMAT治疗质量不产生影响，有影响的Sm、MMS和MDR参数中，随着Sm和MMS值的增大，VMAT计划的剂量分布逐渐变差，但控制点数、机器跳数和照射时间均逐渐减小；随着MDR值增大，VMAT治疗的剂量分布先逐渐变差后不变，控制点数和机器跳数均是先增大后不变，而照射时间是先减小后不变。 结论 Sm、MMS和MDR 3个参数对VMAT计划质量有较大影响，对不同的患者，设置合适的Sm、MMS和MDR值对提高计划质量非常重要。【Abstract】 Objective To investigate the impacts of parameter settings on the quality of plans for the volumetric modulated arc therapy (VMAT) with Monaco treatment planning system. Methods Three patients who underwent VMAT from January to May 2010 were selected. The planning optimizations were processed by setting different planning parameters, including MSC, MSS, SSF, Sm, MMS and MDR, respectively. Then the quality of each plan with a certain set of parameters was evaluated by various evaluation indexes. The differences of quality among different plans were analyzed by comparing these indexes. Results There was no influence on the quality of VMAT planning for the parameter MSC, MSS and SSF to be set with different values. However, the other three parameters, MSC, MSS and SSF , affected the quality of VMAT planning with different values. Along with the aggrandizement of Sm and MMS value, the dose distribution of VMAT plans gradually became bad, while the number of control points, machine monitor units and irradiation time were gradually reduced. And along with the aggrandizement of MDR value, the dose distribution of VMAT plans became bad gradually until a constant state was reached, and both the number of control points and machine monitor units increased at first and then kept constant, while irradiation time decreased at first and then kept constant. Conclusion The selections of parameter Sm, MMS and MDR impact the quality of VMAT planning greatly. It is very important to set the suitable value of Sm, MMS and MDR to get the best planning quality for patients with different complexity.