膀胱充盈度对宫颈癌术后放疗靶区照射剂量的影响

Effect of bladder filling on target dose in cervical cancer post-operative pelvic radiotherapy

目的探讨膀胱充盈度对宫颈癌术后放疗靶区照射剂量的影响。方法选择2013年6月至2014年6月间收治的宫颈癌术后需行调强放疗患者30例,在膀胱充盈状态和排空状态行计算机断层扫描(CT)检查,对膀胱不同状态下的临床靶体积(CTV)、计划靶体积(PTV)、膀胱、直肠、小肠及股骨头的体积变化及平均照射剂量进行比较。结果 (1)膀胱处于充盈状态的膀胱体积明显大于处于排空状态的体积,差异有统计学意义(P<0.05);而CTV、CPV、直肠、小肠及股骨头的体积相比较,差异无统计学意义(P>0.05)。(2)膀胱处于充盈状态时对膀胱及小肠的照射剂量明显低于膀胱排空时,差异有统计学意义(P<0.05);而CTV、CPV、直肠及股骨头照射剂量在膀胱处于充盈状态与排空状态时的差异无统计学意义(P>0.05)。结论在膀胱处于充盈状态下,对宫颈癌术后患者进行调强放疗,可明显减少膀胱及小肠的照射剂量,对膀胱及小肠产生一定的保护作用,有一定的临床应用价值。

Objective To investigate effect of bladder filling on target dose in cervical cancer postoperative pelvic radiotherapy. Methods Totally 30 cases of patients with cervical cancer underwent intensity modulated radiation therapy after surgery in our hospital from June 2013 to June 2014 was selected. Computed tomography（ CT） scan was checked in the state of bladder filling and emptying. The volume changes and average radiation dose of clinical target volume（ CTV）,planning target volume（ PTV）,bladder,rectum,small intestine and caput femoris were compared. Results（ 1） The volume of bladder in the state of bladder filling was significantly larger than that in the state of emptying,the difference was statistically significant（ P〈0. 05）. There was no significant difference in the volume of CTV,PTV,rectum,small intestine and caput femoris between the state of bladder filling and emptying;（ 2） The radiation dose of bladder and small intestine in the state of bladder filling were significantly lower than those in the state of emptying,the difference was statistically significant（ P〈0. 05）. There was no significant difference in the radiation dose of CTV,PTV,rectum and caput femoris between the state of bladder filling and emptying. Conclusions Intensity modulated radiation therapy for cervical cancer patients after surgery in state of bladder filling could significantly reduce the radiation dose of bladder and small intestine,enhance protective effect on bladder and small intestine.