Metabolic Ratio of FDG-PET and Histologic Grading in Cerebral Gliomas

To assess the degree of malignancy in cerebral gliomas at the time of diagnosis, we compared the metabolic ratio using 18F-fluorodeoxyglucose(FDG)-Positron Emission Tomography(PET) with histologic grading and proliferative index(Ki-67) of cerebral gliomas. Materials for this study were histologically-examined 21 gliomas and they were divided into glioblastomas as group 1, anaplastic gliomas as group 2, and low-grade gliomas as group 3. The visual analysis of FDG-PET images showed hypermetabolic lesions in 14(87.5%) out of 16 high-grade gliomas (glioblastomas and anaplastic gliomas), and hypometabolic lesions in 4(80%) out of 5 low-grade gliomas. Tumor to cerebellum ratio(T/Cbll) in FDG-PET was used as metabolic ratio and the values of T/Cbll in each group were 1.30+/-0.10, 0.73+/-0.07, 0.70+/-0.07, respectively. In comparision of T/Cbll between group 1 with remaining two groups, differences were statistically significant(p=0.0002, p=0.0002, respectively), however, there was no statistical difference between group 2 and group 3. The values of Ki-67 were 24.16+/-5.66 in group 1, 8.10+/-2.70 in group 2, 5.46+/-1.23 in group 3, and differences were statistically significant between group 1 and group 2, 3(p=0.015, p=0.015, respectively), but there was no statistical difference between group 2 and group 3. The correlation between T/Cbll and Ki-67 was good and statistically significant(p=0.0047). In conclusion, the visual and semiquantitative analysis of FDG-PET would be helpful in determining the degree of malignancy in cerebral gliomas.

A Study on the Debrisoquine Metabolism in a Group, of Korean Population / 예방의학회지

The genetically determined ability to metabolize debrisoquine(DBR) is related to risk of lung cancer and DBR hydroxylation exhibits wide inter-individual variation. In this study, 100 korean adults were tested for their ability to metabolize DBR. The DBR metabolic phonotype were determined by metabolic ratio (MR, DBR/4-HDBR) which is the percent dose excreted as unchanged DBR divided by the percent dose excreted as 4-hydro-xydebrisoqinne(4-HriBR) in a aliquots of an eight hour urine sample, after 10 mg DBR test dose administration. Analysis was performed on a capillary gas chromatography fitted with electron capture detector. The results were as follows; 1. Geometric mean or DBR MR was 0.32 in male, 0.27 in female, 0.30 in total and the distribution of log(MR) was seemed to follow normal distribution. 2. Metabolic ratio of DBR was higher in non-smoker and non-drinker than in smoker and drinker without any statistically significant difference. 3. None of personal factors was significantly related to DBR MR except age. 4. The DBR metabolic phonotype was extensive metabolizer(EM) 93, intermediate metabolizer (IM) 7 by traditional method and EM 98, IM 3 by Caporaso's method. The poor metabolizer (PM) phenotype was not found by either method. 5. Maximal expected PM phenotype was 0.36% by traditional method and 0.04% by Caporaso's method.