Studies on efficacy evaluation and prediction of side effect of cancer chemotherapy using positron CT.

Glucose demand is one of the physiological characteristics of tumor cells，the myocardium and the brain。^&lt；18&gt；FDG(2-deoxy-2-(^&lt；18&gt；F)fluoro-D-glucose)，positron-labelled glucose analog is taken in tumor cells and the myocardium like glucose but trapped in the glucolysis pathway。On the basis of this property^&lt；18&gt；FDG was used as tracer for detecting cancer with positron emission tomography(PET).We report the results obtained by comparing the change of the image，which was clinically constructed using PET with^&lt；18&gt；FDG during chemotherapy，to the current efficacy evaluation.A total of 10advanced cancer patients were examined.Following the injection of^&lt；18&gt；FDG，serial emission scans by ECAT II were performed on the primary or metastatic tumor as determined by X-CT。We attempted quantification of^&lt；18&gt；FDG concentration in tumors as follows：DAR(Differential Absorption Ratio)=(PET Count X Calibration Factor)/(injected dose/body weight)。In addition，their changes caused by the treatment…More were calculated and denoted as DAR-ratio(DAR at examination/DAR at previous examination)。The categories of efficacy·obtained by the evaluation method of the Japan Society for Cancer Therapy and changes of the scanning images as well as DAR-ratio were compared.In10cases，there was a significant relationship between the efficacy evaluation by current method and that by the change of^&lt；18&gt；FDG-PET imaging.With regard to the change of quantitative expression of^&lt；18&gt；FDG uptake in the tumor，expressed as DAR-ratio，nonresponder had the DAR-ratio of over 1.0，while that of responder was under 0.7。No inconsistency was found between these values and the categories of efficacy evaluation by current method.This method not only expressed morphological change of tumors but can quantify metabolic change in tumor tissues by chemotherapy。Analytic studies on tumor image by^&lt；18&gt；FDG-PET seem to be promising for the evaluation of efficacy of cancer chemotherapy.It was expermentally observed with rats that the^&lt；18&gt；FDG uptake into the heart decreased3days after the adriamycin of THP-Adriamycin administration。The similar result was seen with other kinds of anthracyclines：aclacynomycin or KRN8602(Under Development)。Clinically，the DAR of^&lt；18&gt；FDG-PET-Cardial Image was relatively low in the cases administered with anticancer drugs compared to those without anticancer drugs.We are convinced that the results will contribute to the future study to detect the mechanism that causes cardiotoxicity of anticancer drugs.Less：Less

Glucose demand is one of the physiological characteristics of tumor cells, the myocardium and the brain. ^<18>FDG(2-deoxy-2-(^<18>F)fluoro-D-glucose), positron-labelled glucose analog is taken in tumor cells and the myocardium like glucose but trapped in the glucolysis pathway. On the basis of this property ^<18>FDG was used as tracer for detecting cancer with positron emission tomography(PET).We report the results obtained by comparing the change of the image, which was clinically constructed using PET with ^<18>FDG during chemotherapy, to the current efficacy evaluation.A total of 10 advanced cancer patients were examined. Following the injection of ^<18>FDG, serial emission scans by ECAT II were performed on the primary or metastatic tumor as determined by X-CT. We attempted quantification of ^<18>FDG concentration in tumors as follows : DAR(Differential Absorption Ratio)=(PET count x calibration factor)/(injected dose/body weight). In addition, their changes caused by the treatment … More were calculated and denoted as DAR-ratio(DAR at examination/ DAR at previous examination). The categories of efficacy・obtained by the evaluation method of the Japan Society for Cancer Therapy and changes of the scanning images as well as DAR-ratio were compared. In 10 cases, there was a significant relationship between the efficacy evaluation by current method and that by the change of ^<18>FDG-PET imaging. With regard to the change of quantitative expression of ^<18>FDG uptake in the tumor, expressed as DAR-ratio, nonresponder had the DAR-ratio of over 1.0, while that of responder was under 0.7. No inconsistency was found between these values and the categories of efficacy evaluation by current method.This method not only expressed morphological change of tumors but can quantify metabolic change in tumor tissues by chemotherapy. Analytic studies on tumor image by ^<18>FDG-PET seem to be promising for the evaluation of efficacy of cancer chemotherapy.It was expermentally observed with rats that the ^<18>FDG uptake into the heart decreased 3 days after the adriamycin of THP-Adriamycin administration. The similar result was seen with other kinds of anthracyclines : aclacynomycin or KRN 8602(under development). Clinically, the DAR of ^<18>FDG-PET-Cardial Image was relatively low in the cases administered with anticancer drugs compared to those without anticancer drugs. We are convinced that the results will contribute to the future study to detect the mechanism that causes cardiotoxicity of anticancer drugs. Less