鼻咽癌放疗前后腮腺、颌下腺、甲状腺体积变化与剂量学的研究

发布时间：2019-06-07 08:23

【摘要】：目的:探讨鼻咽癌(nasopharyngeal carcinoma,NPC)根治性放化疗前后腮腺、颌下腺、甲状腺体积的变化趋势与放疗剂量学之间的关系。资料和方法:纵向研究分析汕头大学医学院附属肿瘤医院2008年2月至2009年12月以来我院接受根治性放化疗的鼻咽癌患者65例,所有患者均经病理确诊,无远处转移,既往无头颈部手术史和唾液腺疾病病史。每个患者通过CT增强扫描记录放疗前、放疗后6个月、12个月腮腺、颌下腺、甲状腺体积,并通过治疗计划系统(TPS)计算腮腺、颌下腺、甲状腺受照射剂量,统计分析腮腺、颌下腺、甲状腺体积的变化趋势与放疗剂量学之间的关系。结果:腮腺、颌下腺、甲状腺体积在放疗后12个月内总体均呈缩小趋势。1.放疗前腮腺平均体积为39.40±11.08 cm~3,至放疗后6个月、12个月分别缩小为30.00±8.12 cm~3、26.55±8.30 cm~3,其中6个月时平均缩小22.9%,12个月时平均缩小32.1%,差异均有统计学意义(P值均0.01)。从放疗后6个月至放疗后12个月之间体积缩小9.2%,差异没有统计学意义(P=0.231)。常规放疗组与调强适形放疗组体积缩小率比较,6个月时差异有统计学意义(21.1% :27.2%,P0.01),12个月时差异没有统计学意义(32.8% :30.6%,P=0.625)。放疗后6个月腮腺体积变化与腮腺平均照射剂量相关(P值为0.028,所对应的相关系数r为0.239),放疗后12个月腮腺体积变化与腮腺平均照射剂量相关性很弱(P值为0.171,所对应的相关系数r为-0.120),放疗后6个月、12个月腮腺体积变化与最大照射剂量相关性很弱(P值分别为0.457、0.284,所对应的相关系数r分别为0.094、-0.135)。在调强适形放疗组,利用直线回归分析放疗后6个月及12个月时腮腺体积变化百分比与腮腺平均照射剂量的关系,分别可以得到2个最佳直线方程:y = -0.0086x + 35.651,y = -0.1215x + 32.173(x为腮腺的体积变化百分比,y为腮腺的平均照射剂量,单位Gy)。 2.放疗前颌下腺平均体积为16.65±4.58 cm~3,至放疗后6个月、12个月分别缩小为10.58±3.10 cm~3、9.56±2.94 cm~3,其中6个月时平均缩小35.3%,12个月时平均缩小42.0%,差异均有统计学意义(P值均0.01)。从放疗后6个月至放疗后12个月之间体积缩小6.7%,差异没有统计学意义(P=0.268)。常规放疗组与调强适形放疗组体积下降率比较,6个月及12个月时差异均没有统计学意义(P值分别为0.426、0.845)。放疗后6个月、12个月颌下腺体积变化与颌下腺平均照射剂量相关性很弱(P值分别为0.797、0.636,所对应的相关系数r分别为0.032、0.060),与最大照射剂量相关性也很弱(P值分别为0.128、0.120,所对应的相关系数r分别为0.191、0.195)。 3.放疗前甲状腺平均体积为16.50±4.88 cm~3,至放疗后6个月、12个月分别缩小为13.80±4.21 cm~3、13.11±4.52 cm~3,其中6个月时平均缩小15.5%,12个月时平均缩小20.6%,差异均有统计学意义(P值分别为0.013、0.001)。从放疗后6个月至放疗后12个月之间体积缩小5.1%,差异没有统计学意义(P=0.738)。常规放疗组与调强适形放疗组体积下降率比较,6个月及12个月时差异均有统计学意义(P值均0.01)。放疗后6个月、12个月甲状腺体积变化与甲状腺平均照射剂量均相关(P值分别为0.006、0.002,所对应的相关系数r分别为-0.336、-0.380),与最大照射剂量相关性很弱(P值分别为0.085、0.456,所对应的相关系数r分别为-0.215、-0.094)。利用直线回归分析放疗后6个月及12个月时甲状腺体积变化百分比与甲状腺平均照射剂量的关系,分别可以得到2个最佳直线方程:y = -0.245x + 35.221,y = -0.2821x + 33.199,(x为甲状腺的体积变化百分比,y为甲状腺的平均照射剂量,单位Gy)。结论:本研究表明鼻咽癌患者接受根治性放化疗后均可引起腮腺、颌下腺及甲状腺体积的缩小,其中颌下腺的体积缩小最大。从本研究的结果发现,腮腺在放疗后6个月和甲状腺在放疗后6个月及12个月的体积变化与放疗平均照射剂量具相关性(P值分别为0.028、0.006、0.002),而颌下腺放疗前后体积变化趋势与放疗剂量之间没有明显统计学意义(P0.05)。腮腺在调强适形放疗后6个月评价认为,平均照射剂量的阈值可能为35.7Gy,在调强适形放疗后12个月评价认为,平均照射剂量的阈值可能为32.2Gy;而甲状腺在放疗后6个月评价认为,平均照射剂量的阈值可能为35.2Gy,在放疗后12个月评价认为,平均照射剂量的阈值可能为33.2Gy。
[Abstract]:Objective: To study the relationship between the change of parotid gland, submandibular gland and thyroid volume before and after radical chemoradiotherapy of nasopharyngeal carcinoma (NPC) and the dosimetry of radiotherapy. Materials and Methods: From February 2008 to December 2009,65 patients with nasopharyngeal carcinoma undergoing radical chemoradiotherapy were analyzed and analyzed in the longitudinal study. All the patients were confirmed by pathology and no distant rotation. removed, no history of head and neck surgery and salivary gland disease History. Each patient recorded the parotid gland, submandibular gland and thyroid by the treatment planning system (TPS) before and after radiotherapy,6 months after radiotherapy,12 months after radiotherapy, and the parotid gland, submandibular gland and thyroid by the treatment planning system (TPS), and the parotid gland and submandibular gland were statistically analyzed. The correlation between the change of the volume of the gland and the thyroid and the dosimetry of radiotherapy Results: The total of the parotid gland, submandibular gland and thyroid volume decreased in 12 months after radiotherapy. 1. The mean volume of parotid gland was 39.40-11.08 cm ~ 3 after radiotherapy and 30.00-8.12 cm ~ 3, 26.55-8.30 cm ~ 3 in 12 months after radiotherapy. The mean reduction of the parotid was 22.9% at 6 months and 32.1% in the 12-month period, and the difference was statistically significant (P = 0). 01). The volume was reduced by 9.2% between 6 months after radiotherapy and 12 months after radiotherapy, and the difference was not statistically significant (P = 0.2 31) The difference between the conventional radiotherapy group and the intensity-modulated conformal radiotherapy group was statistically significant at 6 months (21.1%: 27.2%, P0.01), and there was no statistical difference in the 12-month period (32.8%: 30.6%, P = 0.6). 25) Parotid volume change of parotid gland in 6 months after radiotherapy was related to the average dose of parotid gland (P = 0.028, the corresponding correlation coefficient r was 0.239), the volume of parotid gland in 12 months after radiotherapy was very weak (P = 0.171, and the corresponding correlation coefficient r was-0.1). 20) The correlation between the volume change of the parotid gland and the maximum irradiation dose in the 12-month period after radiotherapy was very weak (P = 0.457, 0.284, and the corresponding correlation coefficient r was 0.094,-0.1, respectively). 35) According to the relationship between the percentage of parotid volume and the mean irradiation dose of parotid gland at 6 and 12 months after radiotherapy, two best linear equations can be obtained: y =-0.0086x + 35.651, y =-0.1215x + 32.173 (x is the volume change of parotid gland). %, y is the mean exposure dose of the parotid gland, in unit 2. The mean volume of submandibular gland was 16.65-4.58cm ~ 3, and the mean volume of submandibular gland decreased to 10.58-3.10 cm ~ 3, 9.56-2.94cm ~ 3 in 12 months. The mean reduction of the submandibular gland was 35.3% at 6 months and 42.0% in the 12-month period, and the difference was statistically significant (P-value). 0.01). The volume between 6 months after radiotherapy and 12 months after radiotherapy was reduced by 6.7%, and the difference was not statistically significant (P = 0 .268) There was no statistical significance (P = 0.426,0, respectively) at 6 and 12 months after the comparison of the volume drop rate of the conventional radiotherapy group and the intensity-modulated conformal radiotherapy group. .845) The correlation between the volume change of submandibular gland and the mean irradiation dose of submandibular gland was very weak at 6 months after radiotherapy (P = 0.797, 0.636, the corresponding correlation coefficient r was 0.032, 0.060), and the correlation with the maximum irradiation dose was also weak (P = 0.128, 0.120, and the corresponding correlation coefficient r was 0.191,0, respectively). .3. The mean volume of the thyroid before radiotherapy was 16.50 to 4.88 cm ~ 3, and it was reduced to 13.80 to 4.21 cm ~ 3 and 13.11 to 4.52 cm ~ 3 in 12 months after the radiotherapy. The mean reduction was 15.5% at 6 months and 20.6% in 12 months. The difference was statistically significant (P = 0.013, respectively). (0.001). The volume was reduced by 5.1% between 6 months after radiotherapy and 12 months after radiotherapy, and there was no statistical significance (P = 0.738). There was a significant difference in the volume drop rate of the conventional radiotherapy group and the intensity-modulated conformal radiotherapy group (P <0.05). The correlation between the thyroid volume change and the mean dose of the thyroid (P = 0.006, 0.002, the corresponding correlation coefficient r was-0.336,-0.380, respectively), and the correlation with the maximum exposure dose was very weak (P = 0.08, respectively). 5, 0.456, the corresponding correlation coefficient r is-0.215, -0.094). The relationship between the percentage of thyroid volume change and the mean thyroid irradiation dose at 6 and 12 months after radiotherapy was analyzed by linear regression, and two best linear equations can be obtained: y =-0.245 x + 35.221, y =-0.2821 x + 33.199, (x is thyroid Percent change in volume, y is the average dose of the thyroid Conclusion: The study shows that the patients with nasopharyngeal carcinoma can cause the reduction of parotid gland, submandibular gland and thyroid volume after radical chemoradiotherapy, in which the jaw The results of this study showed that the volume change of parotid gland in 6 months after radiotherapy and 12 months after radiotherapy was related to the mean dose of radiotherapy (P = 0.028, 0.0, respectively). 06, 0.002), and there was no significant difference between the volume change of the submandibular gland before and after radiotherapy and the dose of radiotherapy. The mean exposure dose may be 35.7 Gy, and the threshold of the mean exposure dose may be 32.2 Gy in the 12-month evaluation after the intensity-modulated conformal radiotherapy. The mean exposure dose was considered to be 35.2 Gy in the 6-month post-treatment evaluation and the mean exposure dose was considered to be the threshold for the 12-month post-treatment
【学位授予单位】：汕头大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R739.6

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