Altered expression of metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 in cervical disc herniation patients.

The aim of the current study was to examine matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) expression in patients with cervical disc herniation (CDH). A total of 127 specimens from CDH patients undergoing posterior spinal surgery were obtained for the case group, which was divided into three subgroups: lateral protrusion (N = 102), median protrusion (N = 18), and paramedian protrusion (N = 7). Another 55 specimens from subjects who had cervical spine trauma and underwent spinal canal decompression were obtained for the control group. Routine hematoxylin and eosin staining was performed for pathological diagnosis. Immunohistochemical (IHC) analysis was used to determine MMP-2 and TIMP-2 expression. Under light microscopy, MMP-2-positive cells presented brown-yellow or dark brown staining in the cell membrane or cytoplasm. MMP-2 expression in the case group was significantly higher than that in controls (P < 0.05). Furthermore, MMP-2 expression in the lateral and median protrusion groups was significantly higher compared to that in the paramedian protrusion group (both P < 0.05), while there was no apparent difference in MMP-2 expression between the lateral and median protrusion groups (P > 0.05). IHC results showed that TIMP-2 expression in cases was significantly lower than that in controls (P < 0.05). Spearman correlation analysis indicated that MMP- 2 was negatively correlated with TIMP-2 expression (r = -0.418, P < 0.001). In conclusion, MMP-2 expression increased, whereas TIMP- 2 expression decreased in CDH patients, suggesting that MMP-2 and TIMP-2 expression may contribute to CDH development.

Do high glucose levels have differential effect on FDG uptake in inflammatory and malignant disorders?

BACKGROUND: The association of hyperglycaemia with reduced fluorodeoxyglucose (FDG) uptake by tumour cells is well established. Therefore, it is standard practice that all patients must fast for at least several hours prior to FDG positron emission tomography (PET) imaging. However, the effect of hyperglycaemia on FDG uptake by inflammatory and infectious lesions is unknown. The aim of this study was to investigate this important issue. METHODS: For in vitro studies human mononuclear cells were isolated from 12 normal volunteers and FDG uptake was determined in medium containing differing concentrations of glucose. FDG uptake by human mesothelioma cells was also measured for comparison. For studies involving patients, 416 FDG PET scans of patients with confirmed malignancy (n=321) or benign lesions (n=95) were reviewed retrospectively. The relationship between serum glucose level and FDG uptake by the lesions was assessed utilizing the standardized uptake value (SUV) technique. RESULTS: In the in vitro studies, while FDG uptake by mesothelioma cells decreased as glucose concentration increased, there was no differential uptake of FDG uptake by mononuclear cells at glucose concentrations less than 250 mg x dl(-1). In clinical patients, FDG uptake by malignant lesions was slightly, but negatively affected by serum glucose level (r= -0.21, P<0.01) (glucose range 49-187 mg x dl(-1)). In contrast, FDG uptake by inflammatory lesions was positively associated with serum glucose level (r=0.43, P<0.01) (glucose range 54-215 mg x dl(-1)). DISCUSSION AND CONCLUSION: While the degree of FDG uptake is primarily influenced by the nature of the underlying lesion, serum glucose concentration appears to have a small effect on FDG uptake, which differs between malignant disorders and inflammatory processes. Our data suggest that below a certain level, elevated glucose concentration might not have a negative effect on FDG uptake in inflammatory cells, contrary to that observed in malignant disorders.

18F-fluorodeoxyglucose-positron emission tomography in evaluation of primary cutaneous lymphoma.

BACKGROUND: The diagnosis of primary cutaneous lymphoma (PCL) is currently based on clinical and histological findings and/or relatively invasive procedures such as bone marrow and fine-needle lymph node biopsies. Although computed tomography (CT) is a noninvasive imaging modality that is widely used for staging in patients with lymphoma, it cannot provide information about malignant cutaneous lesions. OBJECTIVES: To investigate the usefulness of (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) in the management of PCL. METHODS: We retrospectively analysed 31 FDG-PET studies in 19 patients with PCL [15 T-cell non-Hodgkin lymphoma (NHL) and four B-cell NHL]. There were 10 men and nine women (age range 23-84 years, mean +/- SD 54 +/- 16). Eleven FDG-PET studies were performed for initial staging and 20 FDG-PET studies were performed for restaging following therapy. Results of FDG-PET were compared with those of CT. Clinical parameters and/or biopsy results of lesions served as reference for the accuracy of PET and CT in evaluating local and metastatic lesions. RESULTS: For the initial staging, FDG-PET had a sensitivity of 82% for the evaluation of local disease and 80% for the detection of distant metastasis. The corresponding values for CT were 55% and 100%, respectively. For restaging of cutaneous lymphoma, FDG-PET had a sensitivity of 86% and specificity of 92% for local recurrence/residual disease and a sensitivity of 100% and specificity of 100% for distant metastasis. The corresponding values for CT were 50% and 83% for local recurrence/residual disease and 100% and 67% for distant metastasis. CONCLUSIONS: FDG-PET has a potential value for initial staging and restaging following therapy in patients with PCL. FDG-PET has higher diagnostic value than CT in the detection both of local disease and distant metastasis.