鼻咽癌靶体积划分的前瞻性临床验证

目的]验证鼻咽癌靶体积划分的合理性和临床疗效。方法]150例初治鼻咽癌患者,69例单纯放疗,81例放化综合治疗。根据靶体积划分方法勾画靶体积,并分别设置相应的计划靶体积;针对靶体积逐步缩野照射。分析治疗后局部区域控制情况以及影像学显示的残留和复发部位与靶体积的关系。结果]治疗后单纯鼻咽残留2例,单纯颈部残留3例,两部位同时残留2例,鼻咽原发灶及颈部转移灶消退率分别为97.3%和96.7%。中位随访时间35.5个月,鼻咽复发6例,颈部复发3例,3年局部和区域控制率分别为95.1%和97.2%。影像学分析显示,鼻咽残留灶和复发灶均位于鼻咽大体肿瘤体积(GTVnx)内;颈部残留病灶均位于颈部大体肿瘤体积(GTVnd)内;颈部复发灶1例位于GTVnd内,2例位于CTV2内。结论]依据该靶体积划分进行放疗,获得较好的局部区域控制,未观察到靶体积外和边缘复发,进一步显示了该靶体积划分较为合理,针对不同靶体积逐步缩野的照射方法是可行的。

Prospective Trial of Target Volume Delineation for Radiotherapy in Nasopharyngeal Carcinoma

Purpose] To verify the rationality of target volume delineation and the clinical effect for nasopharyngeal carcinoma (NPC). Methods] One hundred and fifty patients with NPC were enrolled in this study. Sixty-nine patients were treated by radiotherapy alone, and eighty-one patients received comprehensive radio-chemotherapy. The target volumes and the relevant planning target volumes (PTVs) were delineated. The step-by-step shrinked irradiation was carried out based on the different PTVs. Locoregional control and the relationship between the site of residual or recurrence and target volumes in radiography were analyzed after treatment. Results] Single nasopharynx residual and single cervical residual was found in 2 and 3 cases respectively; 2 sites residual in 2 cases. Primary tumor regression rate and cervical metastasis regression rate were 97.3% and 96.7% respectively. Nasopharyngeal recurrence were found in 6 cases; cervical, 3 cases, with a median follow-up of 35.5 months.The 3-year local and regional control rate were 97.3% and 96.7%, respectively. Imaging analysis showed all nasopharyngeal residual and recurrence were inside the gross tumor volumes of the nasopharynx (GTVnx); cervical residual were inside the gross tumor volumes of the cervical lymph nodes (GTVnd). One cervical recurrent tumors was inside GTVnd; 2, inside CTV2. Conclusions] According to the target volume delineation, satisfied locoregional control was achieved, and no recurrent tumor was observed outside or marginal to the target volumes after radiotherapy. The clinical result suggests that target volume delineation and the step-by-step shrinked irradiated technique are rational and feasible.