Development and validation of the surmising model for volumetric breast density using X-ray exposure conditions in digital mammography.

The use of breast density as a biomarker for breast cancer treatment has not been well established owing to the difficulty in measuring time-series changes in breast density. In this study, we developed a surmising model for breast density using prior mammograms through a multiple regression analysis, enabling a time series analysis of breast density. We acquired 1320 mediolateral oblique view mammograms to construct the surmising model using multiple regression analysis. The dependent variable was the breast density of the mammary gland region segmented by certified radiological technologists, and independent variables included the compressed breast thickness (CBT), exposure current times exposure second (mAs), tube voltage (kV), and patients' age. The coefficient of determination of the surmising model was 0.868. After applying the model, the correlation coefficients of the three groups based on the CBT (thin group, 18-36 mm; standard group, 38-46 mm; and thick group, 48-78 mm) were 0.913, 0.945, and 0.867, respectively, suggesting that the thick breast group had a significantly low correlation coefficient (p = 0.00231). In conclusion, breast density can be accurately surmised using the CBT, mAs, tube voltage, and patients' age, even in the absence of a mammogram image.

Extensive brainstem lesions in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): A case report.

Myelin oligodendrocyte glycoprotein antibody-associated disease is a group of central nervous system demyelinating disorders caused by autoantibodies. While myelin oligodendrocyte glycoprotein antibody-associated disease typically presents as optic neuritis and myelitis in adults, this case report details a patient with brainstem lesions. A 45-year-old male presented with episodes of vertigo, nystagmus, and diplopia in left lateral gaze, which had persisted for 2 months, accompanied by headache. Computed tomography showed hyperdensity extending from the left side of the pons to the middle cerebellar peduncle. Magnetic resonance imaging revealed lesions exhibiting heterogeneous diffusion restriction, with enhancement that included granular and linear patterns. 18F-fluorodeoxyglucose positron emission tomography demonstrated increased uptake in these lesions. Following further evaluation, myelin oligodendrocyte glycoprotein antibody-associated disease was diagnosed. Treatment with high-dose corticosteroids initially alleviated symptoms, but symptoms flared upon reduction of the steroids. This case underscores the importance of considering myelin oligodendrocyte glycoprotein antibody-associated disease in the differential diagnosis of brainstem lesions and discusses distinguishing imaging features from similar conditions.

18 F-FDG Uptake in Pancreatic AL Amyloidosis Associated With Multiple Myeloma.

ABSTRACT: A 60-year-old woman underwent whole-body contrast-enhanced CT because multiple myeloma was suspected. The contrast-enhanced CT showed pancreatic enlargement without main pancreatic duct dilatation and increased peripancreatic fat tissue. 18 F-FDG PET/CT demonstrated diffuse uptake in the enlargement of the pancreas, left and right ventricles, and vertebral column. Biopsy and bone marrow aspiration cytology revealed amyloid light-chain amyloidosis associated with multiple myeloma. Chemotherapy was performed; 18 F-FDG uptake in the pancreas then disappeared, and the pancreatic enlargement decreased. When diffuse 18 F-FDG uptake in pancreatic enlargement is observed in multiple myeloma patients, amyloid light-chain amyloidosis should be considered.

Solitary Fibrous Tumor With an Acute Subdural Hematoma: A Case Report and Review of the Literature.

Solitary fibrous tumor (SFT) is a rare interstitial tumor that originates from various soft tissues, and SFTs occurring within the cranium are extremely rare. While intracranial SFTs with cerebral hemorrhage or subarachnoid hemorrhage have been reported, there have been no reports of intracranial SFTs causing subdural hematoma. In this case, we report on an intracranial SFT accompanied by a subdural hematoma. A 29-year-old female was emergently transported due to the sudden onset of persistent headache and vomiting that began the night before. CT and MRI imaging revealed a hemorrhagic tumor under the tentorium and an acute subdural hematoma extending along the tentorium. The excised tumor was diagnosed as an SFT through histopathological examination. After undergoing radiation therapy, no recurrence has been observed. This is the first case report of an SFT accompanied by a subdural hematoma, and it is vital to recognize that SFTs can be associated with subdural hematomas for proper diagnosis and treatment planning.

Choroid plexus and pituitary gland hemochromatosis induced by transfusional iron overload: Two case reports.

Hemochromatosis is a primary or secondary pathological condition characterized by the deposition of excess iron in the body tissues, which can eventually lead to cellular damage and organ dysfunction. Although excess iron deposition in the central nervous system is rare, involvement of the choroid plexus, pituitary gland, cortical surfaces, and basal ganglia has been reported to date. This case report describes 2 cases of transfusion-induced hemochromatosis involving the choroid plexus and pituitary gland, which were diagnosed by magnetic resonance imaging (MRI). In both cases, gradient echo (GRE) sequences, such as T2 star-weighted image and susceptibility-weighted imaging demonstrated markedly low signal intensity in the choroid plexus. Furthermore, the pituitary gland showed low signal intensity on T2-weighted images in Patient 2. Because these low signal intensities were not seen prior to red blood cell transfusion, they were diagnosed with transfusion-induced hemochromatosis. Brain MRI with GRE sequences was useful in detecting iron deposition in the choroid plexus. Considering that iron deposition in the body tissues can lead to irreversible organ damage, MRI with GRE sequences should be considered for patients with suspected iron overload.

Asymmetric diffuse thyroid uptake on 18F-FDG PET/CT in patient with subacute thyroiditis: Case report and literature review.

A 48-year-old man with an intermittent fever of 39.0oC for more than three weeks underwent computed tomography (CT) and blood testing, which revealed no clues. Antibiotics wereadministered, but his condition did not improve. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) showed right-lobe-dominant diffuse thyroid uptake. On technetium-99m (99mTc) pertechnetate scintigraphy, the thyroid gland could not be visualized, and he was diagnosed with subacute thyroiditis (SAT). When asymmetric 18F-FDG diffuse thyroid uptake on PET/CT is observed in a patient with a fever of unknown origin (FUO), SAT may need to be considered.

Prognostic role of preoperative fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography with an image-based harmonization technique: A multicenter retrospective study.

Objectives: Despite the prognostic impacts of preoperative fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography examination, fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography-based prognosis prediction has not been used clinically because of the disparity in data between institutions. By applying an image-based harmonized approach, we evaluated the prognostic roles of fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters in clinical stage I non-small cell lung cancer. Methods: We retrospectively examined 495 patients with clinical stage I non-small cell lung cancer who underwent fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography examinations before pulmonary resection between 2013 and 2014 at 4 institutions. Three different harmonization techniques were applied, and an image-based harmonization, which showed the best-fit results, was used in the further analyses to evaluate the prognostic roles of fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters. Results: Cutoff values of image-based harmonized fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters, maximum standardized uptake, metabolic tumor volume, and total lesion glycolysis were determined using receiver operating characteristic curves that distinguish pathologic high invasiveness of tumors. Among these parameters, only the maximum standardized uptake was an independent prognostic factor in recurrence-free and overall survivals in univariate and multivariate analyses. High image-based maximum standardized uptake value was associated with squamous histology or lung adenocarcinomas with higher pathologic grades. In subgroup analyses defined by ground-glass opacity status and histology or by clinical stages, the prognostic impact of image-based maximum standardized uptake value was always the highest compared with other fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters. Conclusions: The image-based fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography harmonization was the best fit, and the image-based maximum standardized uptake was the most important prognostic marker in all patients and in subgroups defined by ground-glass opacity status and histology in surgically resected clinical stage I non-small cell lung cancers.

Prognostic significance of the harmonized maximum standardized uptake value of 18F-FDG-PET/CT in patients with resectable oral tongue squamous cell carcinoma: a multicenter study.

OBJECTIVES: To investigate the usefulness of harmonized 18F-FDG-PET/CT parameters for predicting the postoperative recurrence and prognosis of oral tongue squamous cell carcinoma (OTSCC). METHODS: We retrospectively analyzed the cases of 107 OTSCC patients who underwent surgical resection at four institutions in Japan in 2010-2016 and evaluated the harmonized PET parameters of the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) for the primary tumor as the pSUVmax, pMTV, and pTLG. For lymph node metastasis, we used harmonized PET parameters of nodal-SUVmax, nodal-total MTV (tMTV), and nodal-total TLG (tTLG). The associations between the harmonized PET parameters and the patients' relapse-free survival (RFS) and overall survival (OS) were evaluated by the Kaplan-Meier method and Cox proportional hazard regression analysis for model 1 (preoperative stage) and model 2 (preoperative + postoperative stages). RESULTS: The harmonized SUVmax values were significantly lower than those before harmonization (p=0.012). The pSUVmax was revealed as a significant preoperative risk factor for RFS and OS. Nodal-SUVmax, nodal-tMTV, and nodal-tTLG were significant preoperative risk factors for OS. The combination of pSUVmax + nodal-SUVmax significantly stratified the patients into a low-risk group (pSUVmax <3.97 + nodal-SUVmax <2.85 or ≥2.85) and a high-risk group (pSUVmax ≥3.97 + nodal-SUVmax <2.85 or pSUVmax ≥3.97 + nodal-SUVmax ≥2.85) for recurrence and prognosis (RFS: p=0.001; OS: p<0.001). CONCLUSIONS: The harmonized pSUVmax is a significant prognostic factor for the survival of OTSCC patients. The combination of pSUVmax and nodal-SUVmax identified OTSCC patients at high risk for recurrence and poor prognosis at the preoperative stage.

High 18F-FDG Uptake in a Papillary Craniopharyngioma of the Third Ventricle.

ABSTRACT: Craniopharyngioma is a benign tumor classified as grade 1 by the World Health Organization Classification of Tumors of the Central Nervous System. We present a rare case of a high-18F-FDG-avidity papillary craniopharyngioma of the third ventricle. A 65-year-old man underwent CT and MRI examinations for gait disturbance, lower-limb weakness, and urinary incontinence, and an oval solid tumor that extended from the suprasellar region to the third ventricle was identified. 18F-FDG PET/CT showed high accumulation (SUVmax, 22.3) in the tumor. A transventricular endoscopic tumor biopsy led to the diagnosis of papillary craniopharyngioma.

Visualization of tumor hypoxia and re-oxygenation after stereotactic body radiation therapy in early peripheral lung cancer: A prospective study.

BACKGROUND AND PURPOSE: In this study, fluoromisonidazole positron emission tomography (F-MISO PET/CT) was used to evaluate tumor hypoxia and re-oxygenation in patients with lung tumors treated with stereotactic body radiation therapy (SBRT). MATERIALS AND METHODS: Patients with T1-2 N0 lung cancer were included in this study. The prescribed dose was 48-52 Gy in four fractions. F-MISO PET/CT was performed twice, before SBRT and 1-3 days after the first irradiation. The maximum standardized uptake value (SUVmax) and tumor/muscle ratio (TMR) were evaluated as indicators of hypoxia. The threshold for hypoxia was defined as a TMR of 1.30 or more. RESULTS: Between 2016 and 2021, 15 patients were included. Pre-treatment tumor hypoxia was observed in nine tumors (60 %). TMR in all six tumors without pre-treatment hypoxia rose after single high-dose irradiation. In contrast, TMR in six of nine tumors with pre-treatment hypoxia dropped after irradiation, suggesting re-oxygenation. Although no local recurrence was noted, regional and/or distant relapses were seen in four patients (27 %). Of these, three had tumors with abnormal F-MISO uptake. The remaining patient had a tumor without signs of hypoxia on pre-treatment PET/CT. The 2-year progression free survival of patients with tumors with and without pre-treatment hypoxia were 30 % and 63 %, respectively (p = 0.319). CONCLUSION: Tumor hypoxia reduced after single high-dose irradiation. Tumor with F-MISO uptake seems to be an unfavorable prognostic factor in lung SBRT.

Comparison of Conventional Imaging and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Diagnostic Accuracy of Staging in Patients with Intrahepatic Cholangiocarcinoma.

We aimed to examine the accuracy of tumor staging of intrahepatic cholangiocarcinoma (ICC) by using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET-CT). From January 2001 to December 2021, 202 patients underwent PET-CT, CT, and MRI for the initial staging of ICC in two institutions. Among them, 102 patients had undergone surgical treatment. Ninety patients who had a histopathological diagnosis of ICC were retrospectively reviewed. The sensitivity and specificity of 18F-FDG PET-CT, CT, and magnetic resonance imaging (MRI) in detecting tumors, satellite focus, vascular invasion, and lymph node metastases were analyzed. Ninety patients with histologically diagnosed ICC were included. PET-CT demonstrated no statistically significant advantage over CT and MR in the diagnosis of multiple tumors and macrovascular invasion, and bile duct invasion. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET-CT in lymph node metastases were 84%, 86%, 91%, 84%, and 86%, respectively. PET-CT revealed a significantly higher accuracy compared to CT or MRI (86%, 67%, and 76%, p < 0.01, respectively) in the diagnosis of regional lymph node metastases. The accuracy of tumor staging by PET-CT was higher than that by CT/MRI (PET-CT vs. CT vs. MRI: 68/90 vs. 47/90 vs. 51/90, p < 0.05). 18F-FDG PET-CT had sensitivity and specificity values for diagnosing satellite focus and vascular and bile duct invasion similar to those of CT or MRI; however, PET-CT showed higher accuracy in diagnosing regional lymph node metastases. 18F-FDG PET-CT exhibited higher tumor staging accuracy than that of CT/MRI. Thus, 18FDG PET-CT may support tumor staging in ICC.

The usefulness of the total metabolic tumor volume for predicting the postoperative recurrence of thoracic esophageal squamous cell carcinoma.

BACKGROUND: Induction or adjuvant therapies are not always beneficial for thoracic esophageal squamous cell carcinoma (ESCC) patients, and it is thus important to identify patients at high risk for postoperative ESCC recurrence. We investigated the usefulness of the total metabolic tumor volume (TMTV) for predicting the postoperative recurrence of thoracic ESCC. METHODS: We retrospectively analyzed the cases of 163 thoracic ESCC patients (135 men, 28 women; median age of 66 [range 34-82] years) treated at our hospital in 2007-2012. The TMTV was calculated from the fluorine-18 fluorodeoxyglucose (18F-FDG) uptake in the primary lesion and lymph node metastases. The optimal cut-off values for relapse and non-relapse were obtained by the time-dependent receiver operating curve analyses. Relapse-free survival (RFS) was evaluated by the Kaplan-Meier method, and between-subgroup differences in survival were analyzed by log-rank test. The prognostic significance of metabolic parameters and clinicopathological variables was assessed by a Cox proportional hazard regression analysis. The difference in the failure patterns after surgical resection was evaluated using the χ2-test. RESULTS: The optimal cut-off value of TMTV for discriminating relapse from non-relapse was 3.82. The patients with a TMTV ≥3.82 showed significantly worse prognoses than those with low values (p < 0.001). The TMTV was significantly related to RFS (model 1 for preoperative risk factors: TMTV: hazard ratio [HR] =2.574, p = 0.004; model 2 for preoperative and postoperative risk factors: HR = 1.989, p = 0.044). The combination of the TMTV and cN0-1 or pN0-1 stage significantly stratified the patients into low-and high-risk recurrence groups (TMTV cN0-1, p < 0.001; TMTV pN0-1, p = 0.004). The rates of hematogenous and regional lymph node metastasis were significantly higher in the patients with TMTV ≥3.82 than those with low values (hematogenous metastasis, p < 0.001, regional lymph node metastasis, p = 0.011). CONCLUSIONS: The TMTV was a more significantly independent prognostic factor for RFS than any other PET parameter in patients with resectable thoracic ESCC. The TMTV may be useful for the identifying thoracic ESCC patients at high risk for postoperative recurrence and for deciding the patient management.

Automatic detection of primary and metastatic lesions on cervicothoracic region and whole-body bone using a uniform machine-learnable approach for [18F]-FDG-PET/CT image analysis.

We propose a method to detect primary and metastatic lesions with Fluorine-18 fluorodeoxyglucose (FDG) accumulation in the lung field, neck, mediastinum, and bony regions on the FDG-PET/CT images. To search for systemic lesions, various anatomical structures must be considered. The proposed method is addressed by using an extraction process for anatomical regions and a uniform lesion detection approach. The uniform approach does not utilize processes that reflect any region-specific anatomical aspects but has a machine-learnable framework. Therefore, it can work as a lesion detection process for a specific anatomical region if it machine-learns the specific region data. In this study, three lesion detection processes for the whole-body bone region, lung field, or neck-mediastinum region are obtained. These detection processes include lesion candidate detection and false positive (FP) candidate elimination. The lesion candidate detection is based on a voxel anomaly detection with a one-class support vector machine. The FP candidate elimination is performed using an AdaBoost classifier ensemble. The image features used by the ensemble are selected sequentially during training and are optimal for candidate classification. Three-fold cross-validation was used to detect performance with the 54 diseased FDG-PET/CT images. The mean sensitivity for detecting primary and metastatic lesions at 3 FPs per case was 0.89 with a 0.10 standard deviation (SD) in the bone region, 0.80 with a 0.10 SD in the lung field, and 0.87 with a 0.10 SD in the neck region. The average areas under the ROC curve were 0.887 with a 0.125 SD for detecting bone metastases, 0.900 with a 0.063 SD for detecting pulmonary lesions, and 0.927 with a 0.035 SD for detecting the neck-mediastinum lesions. These detection performances indicate that the proposed method could be applied clinically. These results also show that the uniform approach has high versatility for providing various lesion detection processes.

Risk factors for unfavourable outcomes after shunt surgery in patients with idiopathic normal-pressure hydrocephalus.

A number of vascular risk factors (VRFs) have been reported to be associated with idiopathic normal-pressure hydrocephalus (iNPH), but it remains unclear whether these VRFs are related to patient outcomes after shunt surgery. Therefore, we investigated the risk factors for unfavourable outcomes after shunt surgery in iNPH patients using two samples from Tohoku University Hospital and from a multicentre prospective trial of lumboperitoneal (LP) shunt surgery for patients with iNPH (SINPHONI-2). We enrolled 158 iNPH patients. We compared the prevalence of VRFs and clinical measures between patients with favourable and unfavourable outcomes and identified predictors of unfavourable outcomes using multivariate logistic regression analyses. The presence of hypertension, longer disease duration, more severe urinary dysfunction, and a lower Evans' index were predictors of unfavourable outcomes after shunt surgery. In addition, hypertension and longer disease duration were also predictors in patients with independent walking, and a lower Evans' index was the only predictor in patients who needed assistance to walk or could not walk. Our findings indicate that hypertension is the only VRF related to unfavourable outcomes after shunt surgery in iNPH patients. Larger-scale studies are needed to elucidate the reason why hypertension can affect the irreversibility of symptoms after shunt placement.

High 11 C-Methionine Uptake in a Parasellar Inflammatory Pseudotumor.

ABSTRACT: A 20-year-old man had left visual impairment and homonymous hemianopsia. MRI findings suggested enlargement of an optic glioma, because optic glioma was indicated by MRI 14 years earlier without a definite pathological diagnosis. 11 C-methionine (MET) PET showed high uptake in the tumor in the parasellar region. Transnasal endoscopic biopsy was performed, and an inflammatory pseudotumor (IPT) was diagnosed based on histopathological findings. High MET uptake in a parasellar IPT has apparently not been previously reported. Clinicians should be aware of the possibility of high MET uptake in IPT, because this image could provide an interpretation pitfall.

Utility of U-Net for the objective segmentation of the fibroglandular tissue region on clinical digital mammograms.

This study investigates the equivalence or compatibility between U-Net and visual segmentations of fibroglandular tissue regions by mammography experts for calculating the breast density and mean glandular dose (MGD). A total of 703 mediolateral oblique-view mammograms were used for segmentation. Two region types were set as the ground truth (determined visually): (1) one type included only the region where fibroglandular tissue was identifiable (called the 'dense region'); (2) the other type included the region where the fibroglandular tissue may have existed in the past, provided that apparent adipose-only parts, such as the retromammary space, are excluded (the 'diffuse region'). U-Net was trained to segment the fibroglandular tissue region with an adaptive moment estimation optimiser, five-fold cross-validated with 400 training and 100 validation mammograms, and tested with 203 mammograms. The breast density and MGD were calculated using the van Engeland and Dance formulas, respectively, and compared between U-Net and the ground truth with the Dice similarity coefficient and Bland-Altman analysis. Dice similarity coefficients between U-Net and the ground truth were 0.895 and 0.939 for the dense and diffuse regions, respectively. In the Bland-Altman analysis, no proportional or fixed errors were discovered in either the dense or diffuse region for breast density, whereas a slight proportional error was discovered in both regions for the MGD (the slopes of the regression lines were -0.0299 and -0.0443 for the dense and diffuse regions, respectively). Consequently, the U-Net and ground truth were deemed equivalent (interchangeable) for breast density and compatible (interchangeable following four simple arithmetic operations) for MGD. U-Net-based segmentation of the fibroglandular tissue region was satisfactory for both regions, providing reliable segmentation for breast density and MGD calculations. U-Net will be useful in developing a reliable individualised screening-mammography programme, instead of relying on the visual judgement of mammography experts.

Acceptance of Murine Islet Allografts Without Immunosuppression in Inguinal Subcutaneous White Adipose Tissue Pretreated With bFGF.

Prevention of immune rejection without immunosuppression is the ultimate goal of transplant immunobiology. One way to achieve this in cellular transplantation, such as with islet transplantation, is to create a favorable local environment at the transplant site. In the current study, we found that C57BL/6 mice with streptozotocin-induced diabetes remained normoglycemic for >1 year after transplantation of BALB/c islets without immunosuppression when the inguinal subcutaneous white adipose tissue (ISWAT) was the site of transplantation and when the site was pretreated with basic fibroblast growth factor. Mechanistically, mesenchymal stem cells (MSCs) expanded in the ISWAT after the treatment was found to produce transforming growth factor-ß (TGF-ß), and prevention of islet allograft rejection could be achieved by cotransplantation with syngeneic MSCs isolated from the ISWAT after the treatment, which was abolished by anti-TGF-ß antibody treatment. Importantly, TGF-ß-producing cells remained present at the site of cotransplantation up to the end of observation period at 240 days after transplantation. These findings indicate that prevention of islet allograft rejection without immunosuppression is feasible with the use of syngeneic TGF-ß-producing MSCs expanded in the ISWAT after the treatment with bFGF, providing a novel strategy for prevention of islet allograft rejection without immunosuppression.

Prognostic factors for bone metastases from head and neck squamous cell carcinoma: A case series of 97 patients.

Although bone is the second-most frequent site of distant metastases of head and neck squamous cell carcinoma (HNSCC), variable prognostic factors in patients with bone metastases from HNSCC have not been fully investigated. The aim of the present study was to assess the prognostic factors affecting overall survival (OS) in these patients. The medical records of 97 patients at two institutions who developed bone metastases from HNSCC between January 2010 and December 2020 were retrospectively reviewed. A multivariate analysis using a Cox proportional hazards model was performed to identify potential clinical predictive factors for longer OS. The median OS was 7 months, and the 1- and 2-year OS rates for all patients were 35.4 and 19.2%, respectively. The independent predictive factors for longer OS were single bone metastasis, good performance status and administration of systemic chemotherapy. The median OS with each predictor was 10, 10 and 10.5 months, respectively. In a selected group of patients with these three factors, the OS was 14.5 months. In conclusion, single bone metastasis, a good performance status and systemic chemotherapy were independent predictors of longer OS in patients with HNSCC, but their contributions were limited.

Usefulness of respiratory-gated PET acquisition during delayed 18F-FDG PET/CT scanning for patients with liver metastases.

OBJECTIVES: To assess respiratory-gated (RG) positron emission tomography (PET) acquisition for patients with liver metastases during delayed PET/computed tomography (CT) scanning with fluorine-18-fluorodeoxyglucose (18F-FDG). METHODS: Nineteen patients with liver metastases who had undergone early whole-body 18F-FDG PET/CT scans without the RG technique and delayed scans with the RG technique were retrospectively selected. The maximum standardized uptake value (SUVmax) of 41 liver lesions and the tumor-to-liver uptake ratios (TLRs) for these same lesions were compared among three data sets: early non-respiratory-gated (early non-RG) images, delayed non-respiratory-gated (delayed non-RG) images, and delayed respiratory-gated (delayed RG) images. In the delayed non-RG and delayed RG images, the improvements in the TLR, relative to the early non-RG images, were assessed according to lesion size. RESULTS: For liver lesions, the SUVmax of early non-RG, delayed non-RG, and delayed RG images were 6.58±2.34, 7.69±3.08, and 9.47±3.73, respectively. There were significant differences among the three images (P<0.01). The TLR of the delayed RG images was significantly higher than those of the early non-RG and delayed non-RG images (P<0.01). In the delayed RG images, the difference in the TLR improvement for lesions ≤10 mm in size was 15% higher than that for lesions >10 mm in size; in the delayed non-RG images, the difference in the TLR improvement for the same lesion categories was 6%. CONCLUSION: Delayed RG imaging improves the TLR, compared with early non-RG and delayed non-RG imaging, especially for small lesions. RG PET acquisition may be a promising protocol for assessing liver metastases on delayed PET/CT scans.

Lung carcinoma-associated cognitive impairment in a patient with Alzheimer's disease pathology: A case report.

A patient with Alzheimer's disease (AD) pathology when cognitive impairment is detected tends to be diagnosed with AD. However, before diagnosing, we make an effort to exclude other diseases, for example, carcinoma.