高剂量率^（192）铱近距离放射治疗宫颈癌的参考点剂量及参考体积

High Dose Rate Intracavitary Therapy for the Carcinoma of Cervix:Absorbed Dose at Reference Points and Reference Volume

报道１９９０年１０月至１９９１年９月采用体外照射与Ｍｉｃｒｏ－Ｓｅｌｅｃｔｒｏｎ高剂量率（１９２）~铱后装机腔内照射治疗５５例宫颈癌患者的治疗结果。由治疗计划系统制定个体化治疗方案，并按国际辐射剂量与测量委员会３８号文的建议，计算参考点剂量和参考体积。体外及腔内照射Ａ点总剂量为６２００～７５００ｃＧｙ。腔内治疗：膀胱和直肠参考点平均剂量分别为Ａ点剂量的６９．３６％和５６．９３％；盆壁和淋巴结参考点剂量较低；Ａ点１００％剂量水平的参考体积为９９．３９ｃｍ３。分析了高剂量率^（１９２）铱后装机腔内治疗宫颈癌的参考点剂量和参考体积的临床意义。

patients with cervical cancer were treated by combined external and intracavitary radiotherapy.The intracavitary therapy was delivered by Micro-Selectron high dose rate afterloading unit containing 192iridium source;Before the treatment the individiual treatment scheme was formulated for every patient and the absorbed dose at reference points and reference volume were calculated according to the method recommeded by ICRU report(No 38).The total dose at point A was 6 200-7500 cGy.In the intracavitary therapy the mean doses of bladder and rectal reference point were 69.36% and 56.93% respectively.The doses of pelvic wall and lymph nodes reference points were relatively low.The mean reference volum was 99.39 cm3 at the the 100%dose level of point A.In this paper we discussed the clinical value of reference point dose and volum in intracavitray therapy.