Expression of Glut-1 and Glut-3 in untreated oral squamous cell carcinoma compared with FDG accumulation in a PET study

Increased expression of glucose transporter-1(Glut-1) and glucose transporter-3(Glut-3) has been reported in many human cancers. The mechanism of glucose entry into oral squamous cell carcinoma (OSCC) remains unclear. In this study we investigated,in untreated human OSCC, the relationship between tumour fluorine-18 fluoro-2-deoxy-D-glucose(FDG) accumulation and the expression of Glut-1 and Glut-3, as well as the association between the expression of Glut-1 and of Glut-3. All patients underwent FDG positron emission tomography(PET) pre-operatively. Standardised uptake values (SUVs) were used for evaluation of tumour FDG uptake. Final diagnoses were established by histology. Immunohistochemical staining results were evaluated according to the percentage(%) of positive area, intensity and staining score. Tumoursections were stained by immunohistochemistry for Glut-1 and Glut-3. Glut-1 immunostaining revealed that 18(94.7%) of the 19 tumours stained positively, while Gult-3 immunostaining yielded positive findings for 16(84.2%) tumours. Overall, a relatively low level of agreement(36.8%) in the staining score was observed between Glut-1 and Glut-3 expression. No relationship was found between the staining pattern and tumour differentiation or T grade classification in either Glut-1 or Glut-3 immunostaining. Furthermore, no relationship was found between increased FDG SUV and tumour differentiation, but the former did correlate with T grade. In conclusion, high FDG uptake values were seen in OSCC with overexpression of Glut-1 and Glut-3. However, no significant correlation was found between FDG SUV and Glut-1 or Glut-3 expression

Comparison of 11C-choline PET and FDG PET for the differential diagnosis of malignant tumors

We prospectively assessed and compared the usefulness of 11C-choline positron emission tomography (PET) with that of [18F]-2-fluoro-2-deoxy-D-glucose (FDG) PET for the differentiation between benign and malignant tumors. A total of 126 patients with 130 lesions were studied (25 brain tumors, 51 head and neck tumors, 15 bone tumors, 16 lung tumors, and 23 soft tissue tumors). 11C-choline PET and FDG PET were performed from 5 and 40 min, respectively, after injection of 275-370 MBq tracer. PET data were evaluated using the standardized uptake value (SUV) and were analyzed in accordance with the pathologic data. The 11C-choline uptake in malignancies was 3.9 2.3 (n =81), which was significantly higher than that in benign lesions (n =49) (2.6 1.7,P <0.005). The FDG uptake in malignancies was 5.9 3.8 (n =81) and was also significantly higher than that in benign lesions (2.8 2.0, P <0.0001). The 11C-choline uptake in the lesions correlated with FDG uptake (r =0.65, P <0.003).According to an ROC analysis, the areas under the ROC curves (AUCs) for 11C-choline PET were more than 0.8 in bone head and neck, lung, and soft tissue tumors, while the AUC was 0.79 in brain tumors. The AUCs for FDG PET were similarly more than 0.8 in bone, head and neck, lung, and soft tissue tumors, but had a lower value of 0.585 in brain tumors. In brain, head and neck, bone, and soft tissue tumors, 11C-choline showed higher contrast than FDG. In conclusion, it is feasible to use 11C-choline PET for differentiation between malignant and benign tumours, especially of the brain, head ad neck, bone, and soft tissue. However, attention needs to be drawn to the high uptake of 11C-choline in some benign tumors and tumour-like lesions, as this will be of significance in clinical practice

Rhenium-188-HEDP Therapy for the Palliation of Pain Due to Osseous Metastases in Lung Cancer Patients

Rhenium-188-hydroxyethylidine diphosphonate(188Re-HEDP) is a novel and attractive radiopharmaceutical that localizes in areas of osseous metastases and emits beta particles with enerty sufficient to be therapeutically useful. The aim of this study is to evaluate the effectiveness of 188Re-HEDP in patients with lung cancer for the palliation of painful osseous metastases. Intravenous administration of activities rangiong between 1.15 GBq(31 mCi) and 4.6GBq(124 mCi) of 188Re-HEDP was given to each of 30 patients with painful osseous metastases from lung cancer. The patients were clinically followed at weekly intervals for the first 2 months, and monthly thereafter up to 1 year.Hematologic testing was performed before treatment and thereafter for 6 weeks. Pain response was scored by a four-point pain-rating scale as complete, marked, mild, and no response. Prompt and significant relief of bone pain occurred in 80percent with no significant side-effects or hematopoietic toxicity. Forty-six percent(46percent)of the patients discontinued analgesics after treatment. This clical study indicated that 188Re-HEDP can offer significant pain palliation and is a useful radiopharmaceutical for treating painful osseous metastases from lung cancer

In vitro effect of contrast agents during immunoradiometric assay for tumour-associated antigens

The aim of this study was to investigate if contrast agents interfere with the performance of an immunoradiometric assay (IRMA) in vitro for serum tumour-associated antigen. Each of five carcinoembryonic antigen (CEA)-positive sera, CA-130-positive sera and tissue polypeptide antigen (TPA)-positive sera was mixed with six contrast agents: Ioversol 350, Iopamidol 370, Iomeprol 300, Iomeprol 400, Iohexol 300 and Gadopenteic acid in 50:50, 50:20, 50:5.0, 50:1.0, 50:0.5 and 50:0.1ul proportions. Following IRMA, the interference of binding rates in each mixture was calculated, and the serum concentrations of CEA, CA-130 and TPA were estimated and compared with the originals. All contrast agents used were able to inhibit the binding rate with IRMA and the inhibition rates were in proportion to the amount of contrast agent. The detection of serum concentrations of CEA, CA-130 and TPA was significantly inhibited in the mixtures withmore than 5.0 ul of contrast agent in all cases. Apart from Iomeprol 400, there was no significant inhibition of detection at the lowest concentrations of contrast agents. Iomeprol 400 was the strongest inhibitor and Gadopenteic acid the weakest inhibitor for each IRMA of the contrast agents employed. In conclusion, our results demonstrate that contrast agents may reduce the immunoreaction of antibody and antigen and lead to in vitro inhibition during immunoassays. It would be unwise to perform any plasma/serum immunoassay on a sample collected within 24 h of the administration of contrast agent considering the pharmacokinetics

Accelerated Pulmonary Clearance of Aerosolized Tc-99m-Diethylenetriamine Pentaacetic Acid (DTPA) in a Patient with Primary Hyperparathyroidism

Measurement of pulmonary clearance of inhaled Tc-99m DTPA aerosol as a marker of pulmonary damage was performed in a 36-year-old female on whom metastatic calcification was demonstrated in the lungs on a bone scan. Metastatic calcification was the result of metabolic abnormalities due primary hyperparathyroidism. The pulmonary clearance rate of inhaled Tc-99m DTPA showed significant acceleration in both lungs. The patient underwent parathyroidectomy for right superior parathyroid adenoma. Follow-up bone scan and Tc-99m DTPA aerosol clearance studies conducted one year after surgery did not reveal any abnormality

Labeling of Phosphorothioate Antisense Oligonucleotides with Yttrium-90

Novel yttrium-90 (90Y)-labeled phosphorothioate antisense oligonucleotides were designed as a potential targeted radionuclede therapeutic agent for malignant tumors. A 15-mer phosphorothioate antisense oligonucleotide, which was complementary to the translation start region of the N-myc oncogene mRNA, was conjugated with isothiocyanobenzyl ethylenediamine tetraacetic acid (SCN-Bn-EDTA), via a C-5-substituted deoxyuridine that had replaced a thymine in the oligonucleotide, and wa then labeled with 90Y-acetate. Following purification, the radiochemical purity of hte 90Y-Bn-EDTA-phosphorothioate antisence oligonucleotides was estimated by 2.0% agarose gel electrophoresis, and the specific hybridization of 90Y-Bn-EDTA-phosphorothioate antisense oligonucleotide to a phosphorodiester sense oligonucleotide was investigated by 20% polyacrylamide gel electrophoresis in a cell-free system. Radiochemical purity was 98.7 0.4% at 72 h after labeling and 90.3 0.9% after 72-h incubation with human normal serum. The 90Y-Bn-EDTA-phosphorothioate antisense oligonucleotide hybridized specifically to a complementary phosphorodiester sense oligonucleotide. In conclusion, phosphorothioate antisense oligonucleotides can be labeled stably with 90Y using SCN-Bn-EDTA without loss of hybridization properties