宫颈癌根治性手术后辅助调强放疗(IMRT)的临床观察

Intensity-modulated pelvic radiotherapy in postoperative treatment of cervical cancer

目的探讨早期宫颈癌术后具有不良预后因素的患者行盆腔调强放射治疗(IMRT/sIMRT)的近期不良反应和复发率。方法回顾分析2007年1月～2008年6月期间78例早期宫颈癌术后具有不良预后因素行放射治疗的患者资料,其中IMRT组有30例;常规组48例。调强放射治疗方法(IMRT/或sIMRT):CTV上界从腹主动脉分叉处至下界闭孔下缘水平,沿髂血管外放5～7mm勾画,CTV腹向外放10mm/其余方向外放5mm形成PTV,处方剂量95%PTV:45～50GY/1.8～2GY/次×25次;常规前后两野照射:模拟机定位,上界在L3-4之间水平,下界在闭孔下缘,外界在真骨盆最宽处外1.5～2.0cm,处方剂量DT45GY/1.8GY×25次。放疗期间同步顺铂周疗,每周30mg/m^2,4～6周,或顺铂60mg/m^2分3天+5Fu 4g 96小时持续滴入,在放疗d1、29进行。结果年龄30～65岁,中位年龄44.87岁。临床分期、病理类型、病理分级、肌层浸润、切缘、脉管瘤栓、术前放化疗情况以及放化疗中骨髓抑制、肠道反应和泌尿系反应两组无统计学差异,具有淋巴结转移者(IMRT组:20/27,常规组:15/44)采用IMRT/或sIMRT者高于常规前后野照射组(P=0.001)。30例IMRT/sIMRT治疗中2例复发,均在放射野外;48例常规放疗中5例复发,其中4例在放射野内、1例肺转移。结论尽管统计未能显示不良反应及复发差异,但调强放疗通过提高盆腔照射靶区剂量以及减少危机器官受照剂量和体积,减少盆腔内复发,给放射野内复发病灶再次放射治疗提供了剂量空间。

Objective To determine the local effectiveness and toxicity with intensity-modulated radiation therapy （IM- RT/slMRT） for post-hysterectomy adjuvant treatments in cervical cancer patients with high risk factors. Methods Between January 2007 and June 2008, 78 patients at high risk of cervical cancer after hysterectomy were treated with adjuvant pelvic radiotherapy （IMRT group, n =30） or concurrent chemotherapy （conventional group, n =48）. Adjuvant chemotherapy consisted of cisp｜atin （30 mg/m2） for 4-6 cycles every week or cisplatin （60 mg/m2） d1-3 plus 5-Fu 4g iv in 96 h every four weeks. Thirty patients received adjuvant radiotherapy by IMRT. A clinical target volume （CTV） was contoured on each of 10 planning computed tomography of patients from bifurcation of aorta to inferior rim of obturator. Treatment planning was based onvaginal CTVs and regional nodal CTVs. Planning target volume （prFv） was as follows： 10. 0 mm were added anteriorly anti 5 mm were added in all other directions to the CTV. The prescribed （lose was normalized to 45 - 50. 4 Gy in 1.8 - 2. 0 Gy per fraction to PTV. Forty-eight patients underwent conventional two-field radiotherapy （AP-PA radiotherapy） with a 45Gy in I. 8 Gy per fraction given to the whole pelvis from theL3- 4interspace to inferior rim of obturator. Results The median age of ently patients was 44. 87 years old （30 -65 years）. There were no significant differences in stage, hitological type, grade, myometium invation, margin, vaslular space invation, preoperative chemotherapy, marrow impression, and gastrointestinal and urinary reactions between the two groups. Ratio of lymph node metastasis was significantly higher in IMRT group than in conventional group （20/27 vs. 15/44, P =0. 001 ）. Two of 30 patients with IMRT/sIMRT had a recu,Tence outside of the pretreated field. Five of 48 patients with conventional RT had a recurrence ： 4 outside of the pretreated field and the other suffered lung metastasis. Conclusion IMRT remarkably improves the dose distribution of PTV with better locoregional control compared with conventional RT, without increasing the toxicity and recurrence rate.