局部中晚期鼻咽癌四程诱导化疗后肿瘤靶区勾画的研究

目的:探讨根据诱导化疗后肿瘤变化勾画靶区的方式及其临床疗效。方法:回顾性分析2009 年8 月至2013 年8 月中山大学肿瘤防治中心 57 例局部中鼻咽癌患者，行诱导化疗联合同期放化疗。诱导化疗前后鼻咽原发肿瘤范围（gross tumor volume，GTV ）（包括咽后淋巴结）分别为GTVnx-pre 和GTVnx-post 。临床靶区（clinical tumor volume，CTV ）CTVnx 1 为GTVnx-post 外扩10 mm范围，并包括 GTVnx-pre的区域。颈部淋巴结的靶区勾画与上述方法相似，分别命名为 GTVnd-pre、GTVnd-post 和CTVnd 1。CTV 2 为CTVnx 1及CTVnd 1 外扩 5 mm～10 mm范围及淋巴引流选择性预防照射范围。观察全组患者不良反应、近期及远期疗效。结果:GTVnx-pre和GTVnx-post 平均体积分别为 63 .7 cm3和21 .8 cm3（P<0.01 ）；GTVnd-pre和GTVnd-post 平均体积分别为 21 .7 cm3和7.5 cm3（P<0.01 ）。中位随访时间60 .0 个月，全组患者 5 年总生存率（overall survival ，OS）为86 .0%（49 /57 ），无远处转移生存率（distant metastasis free survival rate ，DMFS）为91 .2%（52 /57 ），无局部复发生存率（local recurrence survival rate ，LRFS）为93 .0%（53 /57 ），无进展生存率（progression free survival，PFS）为93 .0%（53 /57 ），复发患者均为GTVnx-post 或GTVnd-post 内复发。结论:鼻咽癌4 个疗程诱导化疗后肿瘤体积明显缩小，按化疗后肿瘤勾画靶区疗效较好，值得进一步验证。 

Target volume delineation in locoregionally advanced nasopharyngeal carcinoma after four circles of induction chemotherapy

Objective:To investigate target volume delineation after four cycles of induction chemotherapy in locoregionally advanced nasopharyngeal cancer (NPC). Methods:From August 2009 to August 2013, 57 patients with stageⅢ-ⅣNPC were treated with induc-tion-concurrent chemotherapy and intensity-modulated radiotherapy. The primary gross tumor volume (GTV), including retropharyn-geal lymph node metastasis before and after induction chemotherapy, was defined as GTVnx-pre and GTVnx-post, respectively, and the clinical target volume (CTV) was divided into two parts:CTV1 and CTV2. The CTVnx1 was defined as the GTVnx-post plus a 10-mm margin, covering the region of GTVnx-pre. The contouring of neck lymph nodes was similar to the primary gross tumor, with the neck lymph nodes GTV and CTV defined as GTVnd-pre, GTVnd-post, and CTVnd1, respectively. CTV2 was defined as CTVnx1 and CTVnd1 plus a 5-mm margin together with the bilateral cervical selective lymph drainage respectively areas. Treatment outcome and toxicity were determined in all patients. Results:The GTVnx-post was significantly smaller than the GTVnx-pre (21.8 cm3 vs. 63.7 cm3, P<0.01), whereas the GTVnd-post was significantly smaller than the GTVnd-pre (21.7 cm3 vs. 7.5 cm3, P<0.01). With a median follow-up of 60.0 months, the 5-year overall survival (OS), locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS), and progres-sion-free survival (PFS) rates were 49/57 (86.0%), 53/57 (93.0%), 52/57 (91.2%), and 53/57 (93.0%) respectively. All locoregional fail-ures occurred in the GTVnx-post or GTVnd-post field with no relapses in the CTVnx1 or CTVnd1. Conclusion:Four cycles of IC can signif-icantly reduce tumor volume. The target volume delineation according to the tumor volume after IC has encouraging long-term treat-ment outcome.