局部晚期宫颈癌腔内放疗的回顾性研究及不同剂量参考点的剂量学比较

发布时间：2018-03-20 13:24

本文选题：宫颈癌　切入点：腔内放疗　出处：《大连医科大学》2014年硕士论文　论文类型：学位论文

【摘要】：目的：回顾性分析局部晚期宫颈癌高剂量率192Ir腔内放疗患者的临床疗效、不良反应及预后相关因素，探讨不同剂量参考点对剂量学的影响。方法：抽取我科30例以A点作为剂量参考点的局部晚期宫颈癌高剂量率192Ir腔内放疗的患者，参考剂量为4-5Gy/次，8-10次，配合盆腔体外放疗（45Gy）。参照国际辐射单位和测量委员会（International Commission on Radiation Unitsand Measurement，ICRU）38号报号对A点的明确定义。参照美国近距离治疗协会（American brachytherapy society，ABS）推荐重新设置新的剂量参考点H点。根治性放疗的累积总剂量将转化为2Gy分次等效生物剂量（equivalent dose in2Gy fractions，EQD2）来进行计算及剂量评估，并分析其临床疗效、不良反应及预后相关因素。对以A点、H点为参考点的两种治疗计划的等剂量曲线内参考体积、膀胱及直肠参考点受量进行比较。结果：1.根治性放疗的累积剂量、疗效及预后分析：三组不同剂量分割组A点的累积总剂量（EBRT+ICBT）分别为76.76GyEQD2、80.09GyEQD2、86.34GyEQD2，所有患者A点累积剂量的平均值为83.60GyEQD2。有效率（CR+PR）为96.7%，其中CR为56.7%，PR为40.0%。3年总生存率为63.3%。本资料中膀胱、直肠（1、2级）急性反应发生率分别10%、26.7%，不同剂量分割组膀胱、直肠急性反应在统计学上无显著差异（P0.05）。Cox单因素分析：肿瘤大小、A点累积剂量及参考体积对生存的影响有统计学意义（P0.05），多因素回归分析：肿瘤大小、参考体积是影响3年总生存率的独立预后因素，而A点累积剂量并非是影响预后的独立因素。 2.以A点、H点为参考点的两种治疗计划的剂量学比较：（1）不同患者A点沿Y轴方向至两侧阴道穹窿连线水平的距离为1.670.31cm，，波动幅度较大（1.15-2.25cm）；（2）A点、H点距坐标原点水平的垂直距离分别为1.6780.238cm、2.1560.448cm，H点的位置高于A点位置（大约0.5cm，P0.05）；（3）以A点、H点为参考点的等剂量曲线内参考体积分别为118.88920.955cm3、125.29820.189cm3，基于H点的等剂量曲线内参考体积要更大（P0.05）；其中，参考体积的径线高度（dh）分别为6.7300.642cm、6.8900.672cm、宽度（dw）分别为5.0040.235cm、5.0890.213cm，两组在统计学上均有显著差异（P0.05），厚度（dt）分别为3.5100.227cm、3.5600.239cm，差异无统计学意义（P0.05）；（4）以A点、H点为参考点的两种治疗计划的膀胱及直肠参考点剂量的比较：RP剂量分别为65.3996.250GyEQD2、67.5657.124GyEQD2；R1剂量分别为66.4927.089GyEQD2、68.1669.185GyEQD2；R2剂量分别为63.8694.954GyEQD2、65.3165.994GyEQD2； BL剂量分别为79.1857.989GyEQD2、80.7736.774GyEQD2，差异均无统计学意义（P0.05），且膀胱、直肠参考点剂量均未超过限制剂量。结论： 1.不同剂量分割组A点的累积总剂量存在差异（76.76-86.34GyEQD2），且比较各剂量组临床疗效、复发或转移、不良反应及生存情况在统计学上均无显著差异。 2.肿瘤大小、A点累积剂量及参考体积是影响局部晚期宫颈癌预后的相关因素，其中肿瘤大小及参考体积是影响3年总生存率的独立预后因素，而A点累积剂量并非是影响预后的独立因素。 3.A点的位置因宫颈口解剖结构的变化而存在众多不确定性，导致A点剂量不能真正反映肿瘤实际受照射剂量，因此分析A点的累积剂量与疗效、复发或转移、不良反应及生存情况之间是无显著相关性的。 4.H点较A点的重复性好、可信度高；以H点为参考点的等剂量曲线内参考体积要更大，对靶区的包绕更充分；同时能提高对受浸润宫旁组织的覆盖，且不会增加膀胱及直肠的受量。
[Abstract]:Objective: To retrospectively analyze the clinical efficacy, adverse reactions and prognosis related factors of patients with locally advanced cervical cancer treated with high dose rate 192Ir intracavitary radiotherapy, and to explore the influence of different dose reference points on dosimetry.
Methods: a total of 30 cases in our department with A as a reference point dose of locally advanced cervical cancer with high dose rate intracavitary radiotherapy in patients with 192Ir, the reference dose of 4-5Gy/ times, 8-10 times, with the in vitro pelvic radiotherapy (45Gy). According to the International Commission on radiation units and measurements (International Commission on Radiation Unitsand Measurement, ICRU) defined No. 38 reported on A point. According to the American Brachytherapy Society (American brachytherapy, society, ABS) is recommended to set the dose reference point H. The new cumulative total dose of radiotherapy will be converted into 2Gy times of biological effective dose (equivalent dose in2Gy fractions, EQD2) to evaluate the calculation and dose. And analysis of the clinical efficacy, adverse reactions and the prognostic factors. To A points, H points for the two treatment plans of reference points to the isodose curve within the reference volume, bladder and rectum reference dose Compare.
Results: 1. radical radiotherapy cumulative dose, curative effect and prognosis analysis: the cumulative total dose of three groups of different dose group segmentation point A (EBRT+ICBT) 76.76GyEQD2,80.09GyEQD2,86.34GyEQD2 respectively, the average value of all patients with A cumulative dose of 83.60GyEQD2. efficiency (CR+PR) was 96.7%, CR for 56.7%, PR for the 40.0%.3 year survival rate of 63.3%. in the bladder, rectum (1,2) acute reaction rates were 10%, 26.7%, different dose fractionation group had no significant difference in the bladder, rectum acute reaction in Statistics (P0.05) single factor analysis: tumor size,.Cox had significant effects A cumulative dose and reference volume on survival (P0.05), multi factor regression Analysis: tumor size, reference volume were independent prognostic factors for the 3 year overall survival rate, and A cumulative dose was not independent prognostic factors.
2. the dosimetry comparison of two treatment plans with A point and H point as reference point:
(1) the distance between the A points of different patients along the Y axis to the bilateral vaginal fornix was 1.670.31cm, and the amplitude of the fluctuation was larger (1.15-2.25cm).
(2) A, the vertical distance from the distance between the H coordinate levels were 1.6780.238cm, 2.1560.448cm, H points above the A point (about 0.5cm P0.05);
(3) to A, H as a reference point to the isodose curve in the reference volume were 118.88920.955cm3125.29820.189cm3, H point isodose curve in the reference volume is greater (P0.05); based on the reference volume diameter height (DH) were 6.7300.642cm, 6.8900.672cm, width (DW) were 5.0040.235cm 5.0890.213cm, the two groups had statistically significant difference (P0.05), thickness (DT) were 3.5100.227cm, 3.5600.239cm, the difference was not statistically significant (P0.05);
(4) to A points, H points for the two treatment plans reference points in the bladder and rectum reference point dose comparison: RP dose was 65.3996.250GyEQD2,67.5657.124GyEQD2; dosage of R1 were 66.4927.089GyEQD2,68.1669.185GyEQD2; R2 dose was 63.8694.954GyEQD2,65.3165.994GyEQD2; dosage of BL was 79.1857.989GyEQD2,80.7736.774GyEQD2, there were no significant differences (P0.05), and bladder, rectum the reference point dose did not exceed the limit dose.
Conclusion:
1. there was a difference in cumulative total dose of A point in different dose group (76.76-86.34GyEQD2), and there was no significant difference in clinical efficacy, recurrence or metastasis, adverse reactions and survival between different dose groups.
2. tumor size, cumulative dose and reference volume at A point are the prognostic factors of locally advanced cervical cancer. Tumor size and reference volume are independent prognostic factors for 3 year overall survival rate, while A point cumulative dose is not an independent prognostic factor.
The positions of 3.A for cervical anatomical changes and exist many uncertainties, leading to A point dose not truly reflect the actual tumor radiation dose, therefore the analysis of cumulative dose and efficacy of A, recurrence or metastasis, and survival between the adverse reaction is no significant correlation.
The 4.H point is more repeatable and reliable than the A point. The reference volume of the isodose curve with H reference point as the reference point is larger, and the target area is more wrapped. Meanwhile, it can improve the coverage of the adjacent tissue and increase the volume of the bladder and rectum.

【学位授予单位】：大连医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R737.33

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