Ⅲ期非小细胞肺癌FDG PET-CT定位三维适形放疗的预后分析

目的 观察Ⅲ期非小细胞肺癌(NSCLC)经氟标记脱氧葡萄糖(18FDG)PET-CT定位后行三维适形放疗的疗效、副反应及失败原因.方法 64例Ⅲ期NSCLC(临床Ⅲa、Ⅲb期)患者用信封法随机分为PET-CT定位三维适形放疗(3DCRT)组(PET-CT组)和普通CT定位3DCRT组(普通CT组).PET-CT组将PET和CT图像融合后进行靶区和重要脏器勾画,制定治疗计划后进行常规分割3DCRT 40 Gy左右,然后适当缩野针对残存肿瘤病灶放疗至总剂量65 Gy左右.普通CT组用普通CT定位设野,3DCRT至相同剂最.所有病例均用TP方案(紫杉醇175 mg/m2第1天,顺铂40 mg第2～4天)辅助化疗6个周期.结果 随访率100%.随访满1、2、3年者分别为40、20、11例,PET-CT组和CT组分别为23和17例、11和9例、7和4例.PET-CT组中13例靶区有改变.PET-CT组和普通CT组完全缓解、部分缓解率分别为13%、66%和19%、53%(x2=0.33,P=0.564),1、2、3年局部控制率分别为84%、66%、53%和72%、59%、44%(x2=2.36,P=0.124),1、2、3年生存率分别为72%、34%、22%和53%、28%、13%(x2=2.46,P=0.117).PET-CT组1、2级肺晚期放射损伤发生率低于普通CT组,分别为28%、53%(x2=4.14,P=0.042).PET-CT组肺门、纵隔淋巴结复发率低于普通CT组,分别为3%和25%(P=0.026)、6%和28%(P=0.043);治疗失败主要原因相似均为远处转移,分别为56%和47%(x2=0.56,P=0.453).结论 PET-CT定位可以优化Ⅲ期NSCLC放疗设野计划,减少肺门和纵隔复发率,但远期生存率无明显提高,远处转移为主要失败原因.

Abstract：

Objective To analyse the long-term result and prognosis of 18 FDG PET/CT positioning three - dimensional conformal radiotherapy ( 3 DCRT ) for stage Ⅲ non - small cell lung cancer. Methods Sixty-four cases with stage Ⅲ non-small cell lung cancer (clinical stage Ⅲa- Ⅲb ) were randomly divided into two groups: PET/CT positioning three-dimensional conformal radiotherapy group (PET/CT group) and the conventional CT positioning three-dimensional conformal radiotherapy group (conventional CT group). In the PET/CT group, the target volume and critical organs were sketched according to PET/CT after fusion of the PET and the CT images; the treatment plan was worked out, then conventional fractionated 3DCRT ( total dosage around 40 Gy) followed by field-shrinked radiotherapy to a total dose of 65 Gy or sowas performed ;in the conventional CT group, the target volume and critical organs were sketched according to CT and 3DCRT were performed to the same total dose; All cases were treated with the TP scheme (paclitaxel 175 mg/m2,d1 ,cisplatin 40 mg,d2-4) adjuvant chemotherapy for 6 cycles after the radiotherapy. Results The followup rate was 100%. The number of patients who completed the 1-,2-and 5-year follow-up were 40,20 and 11 respectively ;The number of patients of the PET/CT group and conventional CT group were 23 and 17,11 and 9,7 and 4 respectively. Target volumes of 13 cases in the PET/CT group were changed. The complete remission and partial remission rates of the two groups were 13% 、66% and 19% 、53% (x2 = 0. 33, P =0. 564), respectively. The 1-,2-and 3-year local control rates of the PET/CT group and conventional CT group were84 % 、66% 、53 % an d72% 、59% 、44% ( x2 = 2.36, P = 0. 124 ) respectively. The1 -, 2-and 3-year survival rates were 72% 、34% 、22% and 53% 、28% 、13% (x2 =2. 46,P =0. 117) respectively. The level-1 and level-2 lungs' and trachea's late radiation injury of the PET/CT group and the conventional CT group were 28% and 53% ( x2 = 4. 14, P = 0. 042 ), respectively. The hilar and mediastinal lymph node recurrence rates of the PET/CT group were lower than those of the conventional CT group, were 3% ,25%(P = 0. 026) and 6%, 28% ( P = 0. 042 ), respectively. The main reason for treatment failure was distant metastasis both in the PET/CT group and conventional CT group,56% and 47% (x2 = 0. 56,P = 0. 453 ),respectively. Conclusions PET/CT, as a method of sketching the target of stage Ⅲ non-small cell lung cancer, can improve the radiation treatment plan, reduce the recurrence rate of hilar and mediastinal lymph nodes, meanwhile it can not improve the long-term survival rate; Distant metastasis was the main reason of failure.