肺癌PET-CT定位的临床价值

The clinical value of lung cancer's PET-CT simulation

目的:探讨18F-FDGPET-CT在肺癌放疗定位中的应用价值。方法:16例肺癌患者以PET-CT检查和定位,扫描数据刻盘输入治疗计划系统,将PET-CT融合图像、PET图像和CT图像进行对比分析。结果:16例中,12例获得了与PET-CT检查前一致的临床分期,4例临床分期提高;9例纵膈淋巴结直径≥1.0cm(1.0-4.2cm)显示为高放射性摄取,4例同时有≥1.0cm和<1.0cm的纵膈淋巴结均显示为高放射性摄取,3例纵膈淋巴结<1.0cm的显示无放射性摄取;在伴有肺不张的6例中,5例清楚区分了肿瘤组织与肺不张组织,1例合并阻塞性肺炎与肿瘤组织无法区分;3例化疗后病例清楚显示原发灶和纵膈淋巴结残存或消失。PET-CT融合图像前后方向位移25%(4/16),头脚方向位移31.3%(5/16)。结论:PET-CT用于肺癌定位可以进一步明确临床分期,准确定位定性肿瘤病灶,确定淋巴结性质,区分肿瘤与肺不张,鉴别治疗后有无肿瘤残存等,进而使放疗靶区勾画准确,放疗计划设计合理。

Objective：To investigate the potential clinical benefit of 18F-FDG PET-CT scan simulation in lung cancer patients.Methods：Checking and simulating 16 lung cancer patients by PET-CT.Scan statistics,burn disks and input the statistics into treatment planning system,then contrast PET-CT fusing images,PET images and CT images.Results：In the 16 cases,the clinical stage had no change in 12 cases;4 cases were upstaged.PET image showed clear uptake in mediastinal lymph nodes whose diameter〉1.0cm（1.0-4.2cm） in 9 cases,and in mediastinal lymph nodes whose diameter 〉1.0cm and 〈1.0cm in 4 cases.In 3 cases,mediastinal lymph node whose diameter 〈1.0cm showed no uptake in PET-CT image.In the 6 cases with pulmonary atelectasis,5 cases clearly divided tumor tissue and atelectatic lung,1 case could not divide obstructive pneumonia and tumor,3 cases showed tumor and mediastinal lymph node＇s remain or disappear after chemotherapy.PET-CT fusing images has a bit shift of 25%（4/16） in the forward and backward direction,and 31.3%（5/16） in the head and feet direction.Conclusion：The use of PET-CT in lung cancer can further make sure the clinical stage,determine the nature of tumor lesions and lymph node precisely before treatment.In the application of radiotherapy,PET-CT can divide tumor and pulmonary atelectasis,distinguish tumor remains after treatment,and delineate GTV precisely,make the plan of radiotherapy more reasonable.