摘要
目的观察调强放射治疗鼻咽癌患者腮腺功能的动态变化。方法33例鼻咽低分化鳞癌患者,其中Ⅰ期1例、Ⅱ期4例、Ⅲ期14例、Ⅳa期14例(92分期),Ⅰ、Ⅱ期行单纯放疗,Ⅲ、Ⅳ期采用放化疗。全部患者接受调强放射治疗,PTVg66Gy/30F,鼻咽和上颈部、下颈部PTVc分别是60Gy/30F、54Gy/30F。在放疗前、放疗中、放疗结束、随访时行放射性核素显像以检测腮腺99mTc清除率测定其摄取指数(UI)、分泌指数(EI),并结合腮腺的剂量体积直方图(DVH)和患者口干症状进行分析。结果腮腺EI值放疗前为0.58±0.13,放疗中为0.17±0.22,放疗结束时为0.09±0.17,随访中为0.42±0.18,放疗中和放疗结束时均比放疗前有下降,随访时比放疗结束时有上升,差异有显著统计学意义(P=0.000)。随访时间<6月、≥6月的EI值分别时0.30±0.21,0.53±0.12,差异有显著统计学意义(P=0.002)。其UI值在4个时间点分别为5.05±2.28、5.78±2.41、5.38±2.10、4.52±2.25,差异无显著统计学意义(P=0.070)。DVH结果:全组腮腺平均剂量35.5Gy,V26平均值为71.3%。腮腺平均剂量≤median和腮腺平均剂量>median的EI值在随访中分别为0.505±0.103、0.373±0.136(P=0.007)。V26≤median、V26>median的EI值在随访中分别为0.490±0.120、0.403±0.136(P=0.086)。两种情况UI差异均无统计学意义(P>0.05)。根据肿瘤放射治疗协作组标准:放疗结束时口干Ⅰ度5例(15%)、Ⅱ度28例(85%),随访中:0度6例(18%)、Ⅰ度23例(70%)、Ⅱ度4例(12%)。平均随访时间为17月(10～22月),1例原发灶、上颈部淋巴结同时复发,3例远处转移,其中1例死亡。结论调强放疗对腮腺功能的影响表现在EI,腮腺放射剂量低,有利于腮腺功能的保护,放疗后腮腺功能随时间的延长而逐步恢复。
Objective To evaluate the parotid glands function and the dose-volume effect in nasopharyngeal carcinoma （NPC） patients with intensity-modulated radiation therapy （IMRT） by radionuclide imaging. Methods From July 2005 to July 2006,the excretion index （EI） and uptake index （UI）of parotids in 33 NPC patients with radical IMRT was examined by radionuclide imaging, prior to IMRT, and at median dose, at the end of radiotherapy, and the follow-up time after radiotherapy. The relationship between parotid function （EI and UI）and DVH were analyzed. Results Scintigraphy showed that the EI of parotid were 0.58 ± 0. 13, 0. 17 ± 0. 22, 0.09 ± 0.17, 0.42 ± 0. 18 at the beginning, the median dose, the end, and the follow-up time, respectively （P =0. 000）. EI decreased significantly after median and total doses as compared to that of pretherapy, and to the lowest level at the end of radiotherapy. During the follow-up time period, a recovery of EI was observed over time. EI were 0.30 ± 0.21 at less than 6 months, and 0. 53 ± 0. 12 at more than 6 months after IMRT （P=0.002）. UI were 5.05±2.28, 5.78±2.41,5.38±2.10 and 4.52±2.25 at the same intervals （P = 0. 070）. The DVH showed that the mean dose of parotid was 35.5 Gy for all patients. During the follow-up time, the EI were 0.51 ± 0.10, 0.37 ± 0.14 at mean dose of parotid median group [mean dose of parotid： （32.88 ± 1.66）Gy] and 〉median group [mean dose of parotid： （38.13±2.05）Gy] （P=0.007）. EI of V26≤median group [mean V26：（62.5±4.4）%], V26〉 median group [mean V26：（80. 1 ± 8. 1）%] were 0.49 ± 0. 12,0.40 ± 0. 14 （P = 0. 086） at the same follow up time. There was no significant difference in UI between the two groups （P 〉 0. 05）. According to the RTOG criteria of xerostomia, 85% of the patients had Grade 2, 15 % had Grade 1 at the moment after IMRT. The average follow-up time was 17 months （ranging 10 to 22 months）, only 12% had Grade 2, 70% had Grade 1, and 18% had Grade 0. There was one patient with local recurrence at nasopharynx and neck, three patients developed distant metastases, one of these patients died. Conclusions EI of parotid decreases significantly after IMRT, but increases during the followup over time although mean dose of parotid is 35.5 Gy. It way contribute to the improvement of EI if the dose of irradiation to the parotid is reduced.
出处
《复旦学报（医学版）》
CAS
CSCD
北大核心
2009年第3期288-291,295,共5页
Fudan University Journal of Medical Sciences
关键词
鼻咽肿瘤
腮腺功能
调强放疗
放射性核素显像
nasopharyngeal neoplasm
parotid gland function
intensity-modulated radiotherapy
radionuclide imaging
