| 摘要: |
| 目的 对比CT、PET-CT图像在局部晚期胰腺癌（local advanced pancreatic carcinoma,LAPC）三维适形放射治疗（three dimensional conformal radiotherapy, 3D-CRT）靶区勾画中的差异，探讨PET-CT在精确放疗方案制定中的可能价值。方法 13例局部晚期胰腺癌确诊患者，分别采用PET-CT融合图像及同机CT图像勾画靶区体积，对比分析大体肿瘤体积(GTV)、临床靶体积(CTV)、计划靶体积(PTV)、周围正常组织受量等指标。结果PET-CT改变GTV、PTV：13例患者靶体积均有改变，GTVCT、GTVPET-CT 分别为(57.3±22.9)、(68.4±31.7)cm3，CTVCT、CTVPET-CT 分别为(119.9±38.7)、(132.7±47.5)cm3，PTVCT、PTVPET-CT分别为(288.6±52.1)、(312.4±79.4)cm3，差异均有统计学意义（P<0.05）；其中6例患者GTV体积增大明显（超过20%），平均增大36.5%（22.15 cm3 ），与PET-CT发现肿瘤浸润范围超出CT确定的肿瘤边界及PET-CT发现了更多的转移淋巴结引起有关。PET-CT改变放疗计划参数：给予相同的靶区剂量60 Gy/30次，基于PET-CT制定的放疗计划与基于CT制定的放疗计划相比，周围正常组织受量均发生相应的变化，但各项指标全组变化不明显，差异无统计意义。结论 应用PET-CT融合图像，可在保证正常组织受量符合临床要求的前提下，较精确地确定胰腺癌放射治疗靶区，有利于制定合理的三维适形放疗计划，但相关结论仍有待进一步大样本研究证实。 |
| 关键词: PET-CT 局部晚期胰腺癌 三维适形放射治疗 |
| DOI：10.3724/SP.J.1008.2014.00791 |
| 投稿时间：2014-05-04修订日期：2014-07-10 |
| 基金项目: |
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| Compare the target volume delineated by CT and PET-CT in 3D-CRT for LAPC |
| Wang Lin-yan,Cai Jin,Liu Hai-tao |
| (Department of Radiotherapy,Fudan University Shanghai Cancer Center) |
| Abstract: |
| Objective To compare the difference between the target volume delineated by CT and that delineated by positron emission tomography and computer tomography(PET-CT)in locally advanced pancreatic carcinoma (LAPC), and observe the impact of PET-CT on planning of three-dimensional conformal radiotherapy (3D- CRT). Methods Thirteen patients with locally advanced pancreatic carcinoma referred for radical radiation therapy, underwent PET-CT scanning. GTV was delineated on the CT imaging and PET-CT fused imaging respectively. The two images were used to develop the radiotherapy planning.Dose-volume histograms (DVH) parameters were selected to be paralleled to compare the quality of the two plans and the impact of PET-CT on radiation plan (RP) was further analyzed. Results (1) PET-CT image altered GTV and PTV: For all patients, the GTVCT versus GTVPET-CT was 57.3±22.9cm3 versus 68.4±31.7cm3,the CTVCT versus CTVPET-CT was 119.9±38.7cm3 versus 132.7±47.5cm3,the PTVCT versus PTVPET-CT was 288.6±52.1cm3 versus 312.4±79.4cm3.The difference was statistically significant. In 6 patients, changes were obvious. The average increase was 36.5%(22.15cm3), due to the extension of the primary tumor beyond that defined by CT and additional lymph node metastases. (2) PET-CT image changed the parameters of DVH: to deliver the same target dose of 60 Gy in 30 fractions, all dose-volume characteristics altered in treatment planning, but there was no significant difference. Conclusions PET-CT image can reflect the relationship of the tumor and normal tissue more accurately. The application of PET-CT fused imaging on target volume delineation not only can provide a satisfactory the parameters of DVH, but also more precise on target volume delineation and planning of three-dimensional conformal radiotherapy for LAPC. |
| Key words: PET-CT local advanced pancreatic carcinoma (LAPC) three dimensional conformal radiotherapy(3D-CRT) |
