局部晚期宫颈癌后装腔内联合组织间插植剂量学及临床疗效分析

Analysis of dosimetry and clinical efficacy of intracavitary/interstitial brachytherapy in locally advanced cervical cancer

目的研究后装腔内/组织间插植近距离治疗(IC/ISBT)与传统后装腔内近距离治疗(ICBT)相比较的剂量学差异及其近期疗效。方法45例局部晚期宫颈癌患者采用IC/ISBT及ICBT方法进行后装近距离治疗,分别对两种治疗方法的A点(A1、A2)、D90%、D100%以及膀胱、结肠、直肠、小肠受量进行计算,同时观察近期疗效。结果IC/ISBT比ICBT放疗A点剂量显著提升(P<0.05);并且IC/ISBT的D90%、D100%也均明显高于ICBT(P<0.05)。外照射后残存肿瘤直径≥3cm时,IC/ISBT比ICBT可获得较高的靶区剂量提升(P<0.05)。IC/ISBT与ICBT的膀胱、直肠、结肠、小肠D2cm^3、D0.1cm3相近(P>0.05)。疗后1、3、6个月的近期疗效IC/ISBT与ICBT相近(P>0.05)。结论局部晚期宫颈癌(残存肿瘤直径≥3cm)后装近距离治疗中IC/ISBT在不增加危及器官受量及降低近期疗效前提下显著地提高了靶区、A点剂量,具有明显剂量学优势。

Objective To study the dosimetric differences and short-term efficacy between intracavitary/interstitial brachytherapy(IC/ISBT)and conventional intracavitary brachytherapy(ICBT).Methods Forty-five patients with locally advanced cervical cancer were treated with IC/ISBT and ICBT.Points A(A1,A2),D90%,D100%,organs at risk,and the doses of bladder,colon,rectum and small intestine were calculated and the short-term efficacy was observed between two groups.Results Point A dose was significantly improved in IC/ISBT compared with ICBT(P<0.05).The D90%and D100%in IC/ISBT were significantly higher than those in ICBT(both P<0.05).After brachytherapy,IC/ISBT could obtain a significantly larger increase in target dose when residual tumor diameter was≥3 cm compared with ICBT(P<0.05).The D2cm3 and D0.1cm^3 of bladder,rectum,colon and small intestine did not significantly differ between IC/ISBT and ICBT(all P>0.05).The 1-,3-and 6-month clinical efficacy did not significantly differ between two technologies(all P>0.05).Conclusion During brachytherapy for locally advanced cervical cancer(residual tumor diameter≥3 cm),IC/ISBT significantly increases the doses of target area and point A without increasing the dose of organs at risk or lowering the short-term clinical efficacy,which has significant dosimetric advantages.