^(18)F-FDG显像对骨肉瘤化疗效果评价的初步研究

Response of osteosarcoma to chemotherapy evaluated by ^(18)F-FDG imaging

目的:探讨18F-FDG显像对术前骨肉瘤患者化疗效果的评价意义。方法:临床诊断为骨肉瘤患者7例,化疗前后分别接受两次18F-FDG显像。观察化疗前后两次图象特征,并进行半定量分析。利用公式(TNR1-TNR2)/TNR1计算获得化疗前后放射性计数率的变化率。经手术获得组织病理学肿瘤坏死率。结果:7例患者化疗后与化疗前图象相比,病灶部位放射性摄取程度均有减低,化疗前后最大计数率有显著性差异(P<0.01),化疗前后平均计数率亦有显著性差异(P<0.01)。7例患者中,4例获得病理组织学坏死率疗效判定。3例肿瘤坏死率大于90%,1例肿瘤坏死率为80%,18F-FDG显像半定量分析,化疗前后计数率的变化率与坏死率具有正相关关系,(TNR1-TNR2)/TNR1max与坏死率的相关系数为0.94,(TNR1-TNR2)/TNR1average与坏死率的相关系数为0.84。结论:18F-FDG显像可用于判断骨肉瘤的化疗效果,半定量分析结果与病理组织学坏死率有正相关关系,有助于准确评估骨肉瘤的坏死率和化疗效果。

Objective： To evaluate potential role of lSF-fluoro-2-deoxy-D-glucose （tSF-FDG） in assessing chemotherapy response of primary osteosarcoma. Methods： Seven patients with osteosarcoma continued by pathology were examined with 18F- FDG imaging beibre and after chemotherapy. Two practiced nuclear medicine doctor observed the image and do the semiquantitative analysis. Tumor to non-tumor radioactivity count ratios （TNR） was used. The radioactivity count variance ratio before and after chemotherapy obtained by using formula（TNR1-TNR2）/TNR1. The histopathological tumor necrosis were obtained by surgery. Result： The radioactivity count before and after chemotherapy （TNR1max and TNR2max,;TNR1averagr and TNR2averagr） had significant difference（P〈0.05）. Four of the 7 patients got histopathological tumor necrosis, which had a significant correlation to the radioactivity count variance ratio. The eorrelation coefficient of （TNR1-TNR2）/TNR1nax and （TNR1-TNR2）/TNR1averagr, with the tumor necrosis were 0.94 and 0.84 respectively. Conclusion： 18F-FDG imaging can be used to assess the chemotherapy response of osteosarcoma noninvasively.The semi-quantitative analysis which has consistency with the histopathological tumor necrosis is helpful in evaluating response of osteosarc oma to chemotherapy.