18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) is usually used for staging or evaluation of treatment response rather than for cancer screening. However, 18F-FDG PET/CT has also been used in Japan for cancer screening in people with no cancer symptoms, and accumulating evidence supports this application of 18F-FDG PET/CT. Previously, we have observed a correlation between the saliva and tumor metabolomic profiles in patients with oral cancer. Hence, if salivary metabolites demonstrate a significant correlation with PET parameters such as the maximum standardized uptake value (SUVmax), they may have the potential to be used as a screening tool before PET/CT to identify patients with high SUVmax. Hence, in this study, we aimed to explore the relationship between salivary metabolites and SUVmax of 18F-FDG PET/CT using previously collected data. 18F-FDG PET/CT was performed for staging 26 patients with oral cancer. The collected data were integrated and analyzed along with quantified salivary hydrophilic metabolites obtained from the same patients with oral cancer and controls (n = 44). In total, 11 metabolites showed significant correlations with SUVmax in the delayed phases. A multiple logistic regression model of the two metabolites showed the ability to discriminate between patients with oral cancer and controls, with an area under the receiver operating characteristic curve of 0.738 (p = 0.001). This study uniquely confirmed a relationship between salivary metabolites and SUVmax of PET/CT in patients with oral cancer; salivary metabolites were significantly correlated with SUVmax. These salivary metabolites can be used as a screening tool before PET/CT to identify patients with high SUVmax, i.e., to detect the presence of oral cancer.

No abstract

Background 18F-fluoromisonidazole positron emission tomography (FMISO-PET) has been used for identification of hypoxic areas in tumors, and since hypoxia causes hypoxia-inducible factor-1 and enhancement of tumor growth, identifying the hypoxic area in the tumor tissue is important. Purpose To evaluate the usefulness of FMISO-PET in the grading of primary brain tumors. Material and Methods FMISO-PET was performed preoperatively on 41 consecutive patients with pathologically confirmed brain tumor. A neuroradiologist retrospectively measured both maximum standardized uptake value (SUVmax) and mean SUV (SUVmean) in the tumor and normal cerebellar parenchyma. Maximum tumor/normal control ratio (T/Nmax) and mean tumor/normal control ratio (T/Nmean) were calculated and analyzed. Results There was a positive correlation between World Health Organization (WHO) grade and both T/Nmax and T/Nmean (r = 0.731 and 0.713, respectively). When all cases were divided into benign (WHO grade II) and malignant groups (III and IV), there were significant differences between the two groups in both T/Nmax and T/Nmean ( P < 0.001). If the cutoff value was defined as T/Nmax = 1.25 and T/Nmean = 1.23, T/Nmax had a sensitivity of 90.0% and a specificity of 90.9% while T/Nmean had a sensitivity of 93.3% and a specificity of 90.9% in differentiating the benign group from the malignant group. Conclusion Both T/Nmax and T/Nmean in FMISO-PET have a positive correlation with primary brain tumor grading, making FMISO-PET useful in diagnosing the malignancy of primary brain tumors.

No abstract

No abstract

We should consider EHEC infection as part of a differential diagnosis when the findings of severe right colitis are seen without enteritis.

Background: The vascular supply to nonfunctioning pituitary adenomas (NFPAs) differs compared with that of the anterior lobe of the normal pituitary gland. In this study, we aimed to identify feeding arteries and flow dynamics using 3.0 T magnetic resonance imaging (MRI) in NFPAs. Methods: We divided 77 cases of NFPA into three groups according to the time-intensity curve (TIC) pattern by dynamic MRI. We also investigated the presence of feeder arteries as a flow void signal on T2-weighted imaging (T2WI). Results: According to the TIC, 39 cases demonstrated an ascending pattern, 10 cases demonstrated a descending pattern, and 28 cases demonstrated a monophasic pattern. Tumor size in the ascending group was larger compared with the descending group (P = 0.0036). Flow void signals were identified in 51 of 77 cases (66.2%) on T2WI. Tumor size was larger in tumors with a flow void signal compared with those without (P < 0.0001). Flow void signals were more frequently observed in the group of ascending pattern compared with the group of monophasic and descending pattern (P = 0.032 and P = 0.003, respectively). Particularly on the caudal side, the difference between the ascending group and the monophasic and descending groups was remarkable (P = 0.0035 and P < 0.0001, respectively). Conclusion: We successfully evaluated the blood supply pattern by the TIC analysis and identified flow voids using 3.0 T MRI. Blood supply pattern was significantly associated with NFPA size. These results suggested that NFPA hemodynamics changes during tumor growth.

Idiopathic hypertrophic pachymeningitis (IHP) is a chronic in‰ammatory disease of unknown cause. We report a case of IHP with bilateral distended subarachnoid space (SAS) of the optic nerves and unilateral visual disturbance. We observed marked amelioration of magnetic resonance (MR) imagingˆndings after initiation of treatment with prednisolone. This radiologicalˆnding implicates optic nerve sheath involvement that aŠects cerebrospinal ‰uid (CSF) dynamics around the optic nerve.