不同定位法应用于鼻咽癌放疗临床分析

目的]探讨鼻咽癌放射治疗时CT模拟定位的远期疗效及后遗症.方法]随机将103例经病理证实的鼻咽癌病例分成CT模拟定位组53例和常规模拟定位组50例.CT模拟定位组先设面颈联合野和下颈切线野,常规分割照射,DT36～40Gy后面颈联合野后界前移避开脊髓,后上颈部采用9～12MeV电子线照射,最后阶段采用6MV X线多野适形缩野照射放疗前的肿瘤区,总量68～74Gy.常规模拟定位按骨性标记,先设面颈联合野和下颈切线野,DT36～40Gy后改成耳颞部侧野和耳后电子线野以及全颈切线野.结果]两组随访5年以上.CT模拟定位组5年生存率、无复发生存率及复发率分别为69.8%、67.9%和7.5%,而常规组分别为50.0%、48.0%和24.0%,两组比较,差异具显著性(P＜0.05).放疗后遗症CT模拟定位组1例耳聋,常规组外展神经麻痹1例,耳聋2例,放射性脑病2例.两组均无放射性脊髓炎.结论]鼻咽癌放射治疗时用CT定位适形放疗较常规模拟定位放疗能提高疗效,减少复发和放疗后遗症.

Analysis of Different Simulations in Radiotherapy for Nasopharyngeal Carcinoma

Purpose] To evaluate the long-term efficacy and sequela of radiotherapy with CT simulation for nasopharyngeal carcinoma(NPC).Method]One hundred and three cases with nasopharyngeal carcinoma proved pathologically were randomized into two groups, 53 patients in group of CT-simulation, 50 patients in group of convention simulation(consim). At CT-simulation, face-neck united beam and under-neck tangent beam were set with the convention fractionation radiotherapy ranging from 36~40Gy.Then,face-neck united beam was moved to avoid the spinal cord damage.The upper-neck tangent beam with electron 9-12MeV was adopted. In the last period, conformal radiotherapy 6MV X was used, the total dose of the nasopharynx, ranged from 68~74Gy.In consim group, face-neck united beam and under-neck tangent beam were set on the bone mark first, ranging from 36~40Gy,then ear-anterior beam, ear-posterior electron beam, and all-neck tangent beam. Result] All cases were followed up over 5 years. 5 year survival rate, progression-free survival rate and recurrence rate in CT-sim and in consim were 69.8%, 67.9% and 7.5% vs 50.0%, 48.0% and 24.0% respectively. Comparing two treatment groups the differences were significant (P<0.05). Some radiotherapeutic sequelas were found: one case with deafness in CT-sim group , one case with abducent paralysis, two cases with deafness and two cases with radioactive encephalopathy in consim group. There was no radioactive myelitis in both groups.Conclusion] Radiotherapy with CT simulation for NPC can increase efficacy camparing to that with consentimal simulation,and decrease recurrence and radiotherapeutic sequela.