三维适形与常规二维放射治疗初治鼻咽癌的配对设计队列研究

A Matched Cohort Analysis of Three-Dimensional Conformal Radiotherapy versus Conventional Radiotherapy for Primary Nasopharyngeal Carcinoma

背景与目的:与常规二维放射治疗相比,鼻咽癌行三维适形放射治疗能更精确的界定靶区和显示肿瘤与周围组织的关系,从而有利于准确照射肿瘤和保护周围正常组织。本研究旨在探讨三维适形放射治疗是否能提高鼻咽癌的局部区域控制率和降低放射后遗症的发生率及严重程度。方法:回顾性分析95例行三维适形放射治疗的初治鼻咽癌患者临床资料,并以F92福州分期、T分期、N分期及性别、年龄为指标,采用逐一配对的方法在二维常规放疗的患者中选取95例作为对照,比较两组的近、远期疗效和晚期放射并发症的发生率。结果:三维组和二维组的5年局部区域控制率(89.7%和90.6%,P=0.783)、局部控制率(91.8%和92.8%,P=0.758)、区域控制率(95.6%和97.8%,P=0.427)和无远处转移生存率(93.1%和86.4%,P=0.152),差异均无统计学意义。但三维组5年总生存率和无进展生存率较二维组似有提高的趋势,分别为91.9%、85.7%和82.0%、71.0%(P值分别为0.072和0.087)。对81例三维组和70例二维组无进展生存的患者进行了晚期放射并发症的随访,三维组口干和张口困难的发生率及严重程度要低于二维组;而听力下降、记忆力下降和颅神经损伤两组差异无统计学意义。结论:对初治鼻咽癌行三维适形放射治疗,能够有效减少唾液腺和颞颌关节晚期放射并发症的发生率及严重程度,并有提高总生存率和无进展生存率的趋势。

BACKGROUND ＆ OBJECTIVE： Comparing with twodimensional conventional radiotherapy （2D CRT）, three-dimensional conformal radiotherapy （3D CRT） features a precise tumor target volume positioning and a three-dimensional display of the tumor and surrounding normal tissues, therefore, helps to spare normal tissues in the radiotherapy for nasopharyngeal carcinoma （NPC）. This study was to explore whether 3D CRT can increase the Iocoregional control rate while reduce the occurrence and severity of radiation-related sequelae for primary NPC patients. METHODS： Clinical data of 95 primary NPC patients, treated by 3D CRT from Feb. 2001 to Apr. 2004, were reviewed. These patients were then compared with a cohort of 95 NPC patients treated by 2D CRT from Jan. 2002 to Dec. 2003, who were matched in respect of ＇92 Fuzhou stage, T stage, N stage, sex and age. The short-term and long-term outcomes and radiation-related sequelae of the two groups were compared. RESULTS： There was no significant differences in the 5-year Iocoregional control rate （89.7% vs. 90.6%, P=0.783）, local control rate （91.8% vs. 92.8%, P= 0.758）, regional control rate （95.6% vs. 97.8%, P=0.427）, and distant metastasis-free survival rate （93.1% vs. 86.4%, P=0.152） between 3D CRT group and 2D CRT group. The 5-year overall and progression-free survival rates were slightly higher in 3D CRT group than in 2D CRT group （91.9% vs. 82.0%, P=0.072; 85.7% vs. 71.0%, P=0.087）. Eighty-one patients in 3D CRT group and 70 patients in 2D CRT group who had survived without disease progression were compared in respect of late radiation-related sequelae. The occurrence rates of moderate or severe xerostomia and trismus were significantly lower in 3D CRT group than in 2D CRT group （37.0% vs. 71.4%, P〈0.001 ; 6.2% vs. 28.6%, P〈0.001 ）. But there were no differences in functional impairment of hearing, memory and injury of cranial nerves between these two groups. CONCLUSION： Comparing with 2D CRT, 3D CRT can reduce the occurrence of late radiation-related sequelae, such as xerostomia and trismus, for primary NPC, and it is likely to prolong overall and progression-free survival.