Catheter embolization for pulmonary arteriovenous malformations during chemotherapy for appendiceal adenocarcinoma: A case report of associated brain abscess.

Pulmonary arteriovenous malformations are rare, abnormal, low-resistance vascular structures that connect a pulmonary artery to a vein. They are common in patients with hereditary hemorrhagic telangiectasia; however, acquired malformations can occur in patients with underlying diseases such as chest trauma, hepatic cirrhosis, and mitral stenosis. Pulmonary arteriovenous malformations bypass the normal pulmonary capillary bed and result in intrapulmonary right-to-left shunts, which may cause central nervous system complications such as brain abscesses or ischemic stroke. Brain abscesses related to pulmonary arteriovenous malformations are not uncommon; however, reports of their occurrence during chemotherapy are limited. Here, we report the case of a 68-year-old woman with bilateral pulmonary arteriovenous malformations and appendiceal adenocarcinoma who developed a bacterial brain abscess during chemotherapy. The infection was treated using abscess drainage and antibiotic therapy. After the brain abscess healed, catheter embolization was performed on the pulmonary arteriovenous malformations and chemotherapy was resumed. The present case suggests that if a patient with a malignancy has a pulmonary arteriovenous malformation, clinicians should pay special attention to complications such as brain abscesses during chemotherapy. For patients who do not urgently need chemotherapy, embolization of the pulmonary arteriovenous malformation before chemotherapy may be a better treatment option.

Multifraction stereotactic radiotherapy utilizing inhomogeneous dose distribution for brainstem metastases: a single-center retrospective analysis.

Brainstem metastases are challenging to manage owing to the critical neurological structures involved. Although stereotactic radiotherapy (SRT) offers targeted high doses while minimizing damage to adjacent normal tissues, the optimal dose fractionation remains undefined. This study evaluated the efficacy and safety of multifraction SRT with an inhomogeneous dose distribution. This retrospective study included 31 patients who underwent 33 treatments for 35 brainstem lesions using linear accelerator-based multifraction SRT (30 Gy in five fractions, 35 Gy in five fractions or 42 Gy in 10 fractions) with an inhomogeneous dose distribution (median isodose, 51.9%). The outcomes of interest were local failure, toxicity and symptomatic failure. The median follow-up time after brainstem SRT for a lesion was 18.6 months (interquartile range, 10.0-24.3 months; range, 1.8-39.0 months). Grade 2 toxicities were observed in two lesions, and local failure occurred in three lesions. No grade 3 or higher toxicities were observed. The 1-year local and symptomatic failure rates were 8.8 and 16.7%, respectively. Toxicity was observed in two of seven treatments with a gross tumor volume (GTV) greater than 1 cc, whereas no toxicity was observed in treatments with a GTV less than 1 cc. No clear association was observed between the biologically effective dose of the maximum brainstem dose and the occurrence of toxicity. Our findings indicate that multifraction SRT with an inhomogeneous dose distribution offers a favorable balance between local control and toxicity in brainstem metastases. Larger multicenter studies are needed to validate these results and determine the optimal dose fractionation.

Neuroradiological, genetic and clinical characteristics of histone H3 K27-mutant diffuse midline gliomas in the Kansai Molecular Diagnosis Network for CNS Tumors (Kansai Network): multicenter retrospective cohort.

This study aims to elucidate the clinical and molecular characteristics, treatment outcomes and prognostic factors of patients with histone H3 K27-mutant diffuse midline glioma. We retrospectively analyzed 93 patients with diffuse midline glioma (47 thalamus, 24 brainstem, 12 spinal cord and 10 other midline locations) treated at 24 affiliated hospitals in the Kansai Molecular Diagnosis Network for CNS Tumors. Considering the term "midline" areas, which had been confused in previous reports, we classified four midline locations based on previous reports and anatomical findings. Clinical and molecular characteristics of the study cohort included: age 4-78 years, female sex (41%), lower-grade histology (56%), preoperative Karnofsky performance status (KPS) scores ≥ 80 (49%), resection (36%), adjuvant radiation plus chemotherapy (83%), temozolomide therapy (76%), bevacizumab therapy (42%), HIST1H3B p.K27M mutation (2%), TERT promoter mutation (3%), MGMT promoter methylation (9%), BRAF p.V600E mutation (1%), FGFR1 mutation (14%) and EGFR mutation (3%). Median progression-free and overall survival time was 9.9 ± 1.0 (7.9-11.9, 95% CI) and 16.6 ± 1.4 (13.9-19.3, 95% CI) months, respectively. Female sex, preoperative KPS score ≥ 80, adjuvant radiation + temozolomide and radiation ≥ 50 Gy were associated with favorable prognosis. Female sex and preoperative KPS score ≥ 80 were identified as independent good prognostic factors. This study demonstrated the current state of clinical practice for patients with diffuse midline glioma and molecular analyses of diffuse midline glioma in real-world settings. Further investigation in a larger population would contribute to better understanding of the pathology of diffuse midline glioma.

Genome-wide association study on meningioma risk in Japan: a multicenter prospective study.

PURPOSE: Although meningiomas are the most common primary intracranial tumors, their genetic etiologies have not been fully elucidated. To date, only two genome-wide association studies (GWASs) have focused on European ancestries, despite ethnic differences in the incidence of meningiomas. The aim of this study was to conduct the first GWAS of Japanese patients with meningiomas to identify the SNPs associated with meningioma susceptibility. METHODS: In this multicenter prospective case-control study, we studied 401 Japanese patients with meningioma admitted in five institutions in Japan, and 50,876 control participants of Japanese ancestry enrolled in Biobank Japan. RESULTS: The quality control process yielded 536,319 variants and imputation resulted in 8,224,735 variants on the autosomes and 224,820 variants on the X chromosomes. This GWAS eventually revealed no genetic variants with genome-wide significance (P < 5 × 10 - 8) and observed no significant association in the previously reported risk variants rs11012732 and rs2686876 due to low minor allele frequency in the Japanese population. CONCLUSION: This is the first GWAS of meningiomas in East Asian populations and is expected to contribute to the development of GWAS research for meningiomas.

Structure-activity relationships of middle-size cyclic peptides, KRAS inhibitors derived from an mRNA display.

Cyclic peptides are attracting attention as therapeutic agents due to their potential for oral absorption and easy access to tough intracellular targets. LUNA18, a clinical KRAS inhibitor, was transformed-without scaffold hopping-from the initial hit by using an mRNA display library that met our criteria for drug-likeness. In drug discovery using mRNA display libraries, hit compounds always possess a site linked to an mRNA tag. Here, we describe our examination of the Structure-Activity Relationship (SAR) using X-ray structures for chemical optimization near the site linked to the mRNA tag, equivalent to the C-terminus. Structural modifications near the C-terminus demonstrated a relatively wide range of tolerance for side chains. Furthermore, we show that a single atom modification is enough to change the pharmacokinetic (PK) profile. Since there are four positions where side chain modification is permissible in terms of activity, it is possible to flexibly adjust the pharmacokinetic profile by structurally optimizing the side chain. The side chain transformation findings demonstrated here may be generally applicable to hits obtained from mRNA display libraries.

Association of increasing gross tumor volume dose with tumor volume reduction and local control in fractionated stereotactic radiosurgery for unresected brain metastases.

BACKGROUND: Fractionated stereotactic radiosurgery (fSRS) is an important treatment strategy for unresected brain metastases. We previously reported that a good volumetric response 6 months after fSRS can be the first step for local control. Few studies have reported the association between gross tumor volume (GTV) dose, volumetric response, and local control in patients treated with the same number of fractions. Therefore, in this study, we aimed to investigate the GTV dose and volumetric response 6 months after fSRS in five daily fractions and identify the predictive GTV dose for local failure (LF) for unresected brain metastasis. METHODS: This retrospective study included 115 patients with 241 unresected brain metastases treated using fSRS in five daily fractions at our hospital between January 2013 and April 2022. The median prescription dose was 35 Gy (range, 30-35 Gy) in five fractions. The median follow-up time after fSRS was 16 months (range, 7-66 months). RESULTS: GTV D80 > 42 Gy and GTV D98 > 39 Gy were prognostic factors for over 65% volume reduction (odds ratio, 3.68, p < 0.01; odds ratio, 4.68, p < 0.01, respectively). GTV D80 > 42 Gy was also a prognostic factor for LF (hazard ratio, 0.37; p = 0.01). CONCLUSIONS: GTV D80 > 42 Gy in five fractions led to better volume reduction and local control. The goal of planning an inhomogeneous dose distribution for fSRS in brain metastases may be to increase the GTV D80 and GTV D98. Further studies on inhomogeneous dose distributions are required.

Pathological characteristics of reoperated regrowing clinically nonfunctioning pituitary tumor cases in comparison with initial surgical cases.

Objective: Postoperative nonfunctioning pituitary tumor (NFPT) regrowth is a significant concern, but its predictive factors are not well established. This study aimed to elucidate the pathological characteristics of NFPTs indicated for reoperation for tumor regrowth. Methods: Pathological, radiological, and clinical data were collected from patients who underwent repeat operation for NFPT at Moriyama Memorial Hospital (MMH) between April 2018 and September 2023. For comparison, we also gathered data from patients who underwent initial surgery for NFPT during the same period at MMH. Results: Overall, 61 and 244 NFPT patients who respectively underwent reoperation and initial operation were evaluated. The mean period between the previous operation and reoperation was 113 months. Immunonegativity for any adenohypophyseal hormone was significantly more frequent in the reoperation group than in the initial operation group. In addition, the rate of hormone-negative but transcription factor-positive (H-/TF+) tumors among silent gonadotroph tumors was significantly higher in the reoperation group than in the initial operation group. Furthermore, seven silent corticotroph tumors (SCTs) in the reoperation group were ACTH-negative but TPIT-positive. Because most of the previous surgeries were performed in other hospitals a long time ago, we could procure the previous pathological results with immunohistochemistry (IHC) only from 21 patients. IHC for TF had not been performed in all the previous specimens. IHC for adenohypophyseal hormone was almost the same as the current results, and many H-/TF+ tumors were previously diagnosed as NCT. In addition, the reoperated patients were classified into 3 groups on the basis of the condition of the previous operation: gross total resection (GTR), 12 patients; subtotal resection (STR), 17 patients; and partial resection (PR), 32 patients. The mean Ki-67 LI in the GTR, STR, and PR subgroups were 1.82, 1.37, and 0.84, respectively, with the value being significantly higher in the GTR subgroup than in the PR subgroup (P < 0.05). Conclusions: The ratio of H-/TF+ tumors is significantly higher in symptomatically regrown tumors than in the initial cases, which used to be diagnosed as NCT. PR cases tend to grow symptomatically in a shorter period, even with lower Ki-67 LI than GTR cases.

Prognostic impact of clinical and radiological factors on leptomeningeal metastasis from solid cancers.

PURPOSE: The number of leptomeningeal metastasis (LM) patients has increased in recent years, as the cancer survival rates increased. An optimal prediction of prognosis is essential for selecting an appropriate treatment. The European Association of Neuro-Oncology-European Society for Medical Oncology (EANO-ESMO) guidelines for LM proposed a classification based on the cerebrospinal fluid cytological findings and contrast-enhanced magnetic resonance imaging (MRI) pattern. However, few studies have validated the utility of this classification. This study aimed to investigate the prognostic factors of LM, including the radiological and cytological types. METHODS: We retrospectively analyzed the data of 240 adult patients with suspected LM who had undergone lumbar puncture between April 2014 and September 2021. RESULTS: The most common primary cancer types were non-small-cell lung cancer (NSCLC) (143 (60%)) and breast cancer (27 (11%)). Positive cytology results and the presence of leptomeningeal lesions on contrast-enhanced MRI correlated with decreased survival in all patients. Nodular lesions detected on contrast-enhanced magnetic resonance were a poor prognostic factor in cytology-negative patients, while contrast-enhanced patterns had no prognostic significance in cytology-positive patients. Systemic therapy using cytotoxic agents and molecular-targeted therapy after LM diagnosis correlated with prolonged survival, regardless of the cytology results. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment and systemic chemotherapy after LM improved the survival of EGFR-mutated and wild-type NSCLC patients with positive cytology results. CONCLUSIONS: This study validated the efficacy of prognostication according to the EANO-ESMO guidelines for LM. Systemic therapy after LM diagnosis improves the survival of NSCLC patients.

Prediction of MGMT promotor methylation status in glioblastoma by contrast-enhanced T1-weighted intensity image.

Background: The study aims to explore MRI phenotypes that predict glioblastoma's (GBM) methylation status of the promoter region of MGMT gene (pMGMT) by qualitatively assessing contrast-enhanced T1-weighted intensity images. Methods: A total of 193 histologically and molecularly confirmed GBMs at the Kansai Network for Molecular Diagnosis of Central Nervous Tumors (KANSAI) were used as an exploratory cohort. From the Cancer Imaging Archive/Cancer Genome Atlas (TCGA) 93 patients were used as validation cohorts. "Thickened structure" was defined as the solid tumor component presenting circumferential extension or occupying >50% of the tumor volume. "Methylated contrast phenotype" was defined as indistinct enhancing circumferential border, heterogenous enhancement, or nodular enhancement. Inter-rater agreement was assessed, followed by an investigation of the relationship between radiological findings and pMGMT methylation status. Results: Fleiss's Kappa coefficient for "Thickened structure" was 0.68 for the exploratory and 0.55 for the validation cohort, and for "Methylated contrast phenotype," 0.30 and 0.39, respectively. The imaging feature, the presence of "Thickened structure" and absence of "Methylated contrast phenotype," was significantly predictive of pMGMT unmethylation both for the exploratory (p = .015, odds ratio = 2.44) and for the validation cohort (p = .006, odds ratio = 7.83). The sensitivities and specificities of the imaging feature, the presence of "Thickened structure," and the absence of "Methylated contrast phenotype" for predicting pMGMT unmethylation were 0.29 and 0.86 for the exploratory and 0.25 and 0.96 for the validation cohort. Conclusions: The present study showed that qualitative assessment of contrast-enhanced T1-weighted intensity images helps predict GBM's pMGMT methylation status.

Validation of a New Methodology to Create Oral Drugs beyond the Rule of 5 for Intracellular Tough Targets.

Establishing a technological platform for creating clinical compounds inhibiting intracellular protein-protein interactions (PPIs) can open the door to many valuable drugs. Although small molecules and antibodies are mainstream modalities, they are not suitable for a target protein that lacks a deep cavity for a small molecule to bind or a protein found in intracellular space out of an antibody's reach. One possible approach to access these targets is to utilize so-called middle-size cyclic peptides (defined here as those with a molecular weight of 1000-2000 g/mol). In this study, we validated a new methodology to create oral drugs beyond the rule of 5 for intracellular tough targets by elucidating structural features and physicochemical properties for drug-like cyclic peptides and developing library technologies to afford highly N-alkylated cyclic peptide hits. We discovered a KRAS inhibitory clinical compound (LUNA18) as the first example of our platform technology.

First navigation with wireless muometric navigation system (MuWNS) in indoor and underground environments.

Navigation in indoor and underground environments has been extensively studied to realize automation of home, hospital, office, factory and mining services, and various techniques have been proposed for its implementation. By utilizing the relativistic and penetrative nature of cosmic-ray muons, a completely new wireless navigation technique called wireless muometric navigation system (MuWNS) was developed. This paper shows the results of the world's first physical demonstration of MuWNS used on the basement floor inside a building to navigate (a person) in an area where global navigation satellite system (GNSS)/ global positioning system (GPS) signals cannot reach. The resultant navigation accuracy was comparable or better than the positioning accuracy attainable with single-point GNSS/GPS positioning in urban areas. With further improvements in stability of local clocks used for timing, it is anticipated that MuWNS can be adapted to improve autonomous mobile robot navigation and positioning as well as other underground and underwater practical applications.

Development of Orally Bioavailable Peptides Targeting an Intracellular Protein: From a Hit to a Clinical KRAS Inhibitor.

Cyclic peptides as a therapeutic modality are attracting a lot of attention due to their potential for oral absorption and accessibility to intracellular tough targets. Here, starting with a drug-like hit discovered using an mRNA display library, we describe a chemical optimization that led to the orally available clinical compound known as LUNA18, an 11-mer cyclic peptide inhibitor for the intracellular tough target RAS. The key findings are as follows: (i) two peptide side chains were identified that each increase RAS affinity over 10-fold; (ii) physico-chemical properties (PCP) including Clog P can be adjusted by side-chain modification to increase membrane permeability; (iii) restriction of cyclic peptide conformation works effectively to adjust PCP and improve bio-activity; (iv) cellular efficacy was observed in peptides with a permeability of around 0.4 × 10-6 cm/s or more in a Caco-2 permeability assay; and (v) while keeping the cyclic peptide's main-chain conformation, we found one example where the RAS protein structure was changed dramatically through induced-fit to our peptide side chain. This study demonstrates how the chemical optimization of bio-active peptides can be achieved without scaffold hopping, much like the processes for small molecule drug discovery that are guided by Lipinski's rule of five. Our approach provides a versatile new strategy for generating peptide drugs starting from drug-like hits.

Robust increase in glucagon secretion after oral protein intake, but not after glucose or lipid intake in Japanese people without diabetes.

Few studies in Asian populations have analyzed how glucagon secretion is affected by ingested glucose, proteins or lipids, individually. To investigate the fluctuations of glucagon secretion after the intake of each of these nutrients, 10 healthy volunteers underwent oral loading tests using each of glucose, proteins and lipids, and blood levels of glucose, insulin and glucagon were measured every 30 min for 120 min. Whereas glucagon secretion was suppressed and minimally affected by oral glucose intake and lipid intake, respectively, oral protein intake robustly increased glucagon secretion, as well as insulin secretion. Further studies are needed to elucidate the mechanism by which protein loading increases glucagon secretion.

Clinical decision-making based on 11C-methionine PET in recurrent Cushing's disease with equivocal MRI findings.

OBJECTIVE: Diagnosis and accurate localization of recurrent tumors in Cushing's disease (CD) are challenging, especially after multiple transsphenoidal surgeries (TSSs) or radiosurgery. Even experts face difficulties in detecting these recurrent tumors, and a favorable surgical outcome is not guaranteed. In this report, the authors aimed to determine the usefulness of 11C-methionine positron emission tomography (MET-PET) for evaluating patients with recurrent CD with inconclusive magnetic resonance imaging (MRI) lesions and to develop a treatment protocol for these cases. METHODS: In this retrospective study of patients with recurrent CD in the period between April 2018 and December 2022, the authors assessed the usefulness of MET-PET in determining whether equivocal MRI findings were recurrent tumors or postsurgical cavities and deciding further treatment options. All patients had undergone at least one TSS, and most had undergone multiple TSSs and had pathologically confirmed corticotroph tumors with hypercortisolemia. RESULTS: Overall, 15 patients with recurrent CD (10 females and 5 males) were included, all of whom had undergone MET-PET. All patients had been subjected to multiple treatments, including TSSs or radiosurgeries. Their MRI scans demonstrated less-enhanced lesions that were not confirmed as recurrences even with cutting-edge MRI because they could not be distinguished from postsurgical changes with confidence. MET uptake was positive in 8 patients (9 examinations) and negative in 7. Following MET-PET, repeat TSS was performed in 5 patients. Corticotroph tumors were identified in all 5 patients, even though one of them had negative MET uptake. The MET uptake precisely identified a tumor location on the opposite side of the MRI-suspected lesion in 2 patients. Meanwhile, patients with negative uptake and mild hypercortisolism were only observed. Nonsurgical options were also used in other patients: temozolomide (TMZ) was administered in 2 patients owing to a prior history of multiple TSSs and radiosurgery and the drug-resistant nature of the disease. TMZ was highly effective in these patients; their Cushing's symptoms ameliorated, and their adrenocorticotropic hormone and cortisol levels continued to decline. Interestingly, MET uptake disappeared following TMZ treatment. CONCLUSIONS: MET-PET is extremely useful for confirming equivocal lesions on MRI in patients with recurrent CD and for deciding further treatment options. The authors propose a novel protocol based on MET-PET results for treating patients with relapsing CD in whom the recurrent tumors cannot be confirmed with MRI.

ATP6AP2 is robustly expressed in pancreatic ß cells and neuroendocrine tumors, and plays a role in maintaining cellular viability.

ATP6AP2, also known as (pro)renin receptor, has been shown to be expressed in several tissues including pancreatic ß cells. Whereas ATP6AP2 plays an important role in regulating insulin secretion in mouse pancreatic ß cells, the expression profiles and roles of ATP6AP2 in human pancreatic endocrine cells and neuroendocrine tumor cells remain unclear. Here in this study, we investigated the expression profiles of ATP6AP2 in pancreatic endocrine cells, and found that ATP6AP2 is robustly expressed in pancreatic insulinoma cells as well as in normal ß cells. Although ATP6AP2 was also expressed in low-grade neuroendocrine tumors, it was not or faintly detected in intermediate- and high-grade neuroendocrine tumors. Knockdown experiments of the Atp6ap2 gene in rat insulinoma-derived INS-1 cells demonstrated decreased cell viability accompanied by a significant increase in apoptotic cells. Taken together, these findings suggest that ATP6AP2 plays a role in maintaining cellular homeostasis in insulinoma cells, which could lead to possible therapeutic approaches for endocrine tumors.

The use of a scented face mask in pediatric patients may facilitate mask acceptance before anesthesia induction.

Background: Scented face masks are commonly used during the induction phase of anesthesia. The present study investigated whether the use of a scented mask improved mask acceptance before the slow induction of anesthesia in pediatric patients. Methods: This prospective, randomized controlled trial enrolled patients aged 2-10 years who were scheduled to undergo surgery under general anesthesia. Patients were randomly assigned to either of regular unscented (control group) or scented (experimental group) face masks before anesthesia induction with a parent. The primary outcome was the mask acceptance score, rated on a validated 4-point from 1 point (not afraid; easily accepts the mask) to 4 points (afraid of a mask; crying or struggling). The secondary outcome was heart rate assessed by pulse oximetry in the pediatric ward before transfer to the operating room (OR), at the entrance to the OR, at the patient notification of mask fitting by the anesthesiologist, and after mask fitting. Results: Seventy-seven patients were accessed for eligibility, with 67 enrolled in the study: 33 in the experimental group and 34 in the control group. Mask acceptance was significantly greater among patients aged 2-3 years in the experimental than in the control group (p < 0.05). Conclusion: The use of a scented mask can improve mask acceptance before anesthesia induction with a parental presence in pediatric patients aged 2-3 years.Clinical Trial Registration: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000040819.

Linear accelerator-based stereotactic radiotherapy for brain metastases, including multiple and large lesions, carries a low incidence of acute toxicities: a retrospective analysis.

BACKGROUND: Data on acute toxicities after stereotactic radiotherapy (SRT) for brain metastases, including multiple and large lesions, are lacking. We aimed to evaluate the incidence and nature of toxicities immediately after SRT using a linear accelerator. METHODS: This retrospective study reviewed the medical records of 315 patients with brain metastases treated with SRT at our institution between May 2019 and February 2022. In total, 439 SRT sessions were performed for 2161 brain metastases. The outcome of interest was immediate side effects (ISEs), defined as new or worsening symptoms occurring during SRT or within 14 days after the end of SRT. RESULTS: Grade ≥ 2 and ≥ 3 ISEs occurred in 16 (3.6%) and 7 (1.6%) cases, respectively. Among 63 treatments for 10 or more lesions (range: 10-40), 1 (1.6%) ISE occurred. Among 22 treatments for lesions with a maximum tumor volume of > 10 cc, 2 (9.1%) ISEs occurred. Grade ≥ 3 ISEs included 1, 4, 1, and 1 cases of grade 3 nausea, grade 3 new-onset partial and generalized seizures, grade 3 obstructive hydrocephalus, and grade 5 intracranial hemorrhage, respectively. ISEs were more common in patients with a larger maximum tumor volume, primary sites other than lung and breast cancer, and pre-treatment neurological symptoms. CONCLUSION: SRT using a linear accelerator for brain metastases, including multiple and large lesions, is safe, with a low incidence of ISEs. Serious complications immediately after SRT are rare but possible; therefore, careful follow-up is necessary after treatment initiation.

Neurite orientation dispersion and density imaging and diffusion tensor imaging to facilitate distinction between infiltrating tumors and edemas in glioblastoma.

BACKGROUND: Glioblastomas are highly infiltrative tumors, and differentiating between non-enhancing tumors (NETs) and vasogenic edema (Edemas) occurring in the non-enhancing T2-weighted hyperintense area is challenging. Here, we differentiated between NETs and Edemas in glioblastomas using neurite orientation dispersion and density imaging (NODDI) and diffusion tensor imaging (DTI). MATERIALS AND METHODS: Data were collected retrospectively from 21 patients with primary glioblastomas, three with metastasis, and two with meningioma as controls. MRI data included T2 weighted images and contrast enhanced T1 weighted images, NODDI, and DTI. Three neurosurgeons manually assigned volumes of interest (VOIs) to the NETs and Edemas. The DTI and NODDI-derived parameters calculated for each VOI were fractional anisotropy (FA), apparent diffusion coefficient (ADC), intracellular volume fraction (ICVF), isotropic volume fraction (ISOVF), and orientation dispersion index. RESULTS: Sixteen and 14 VOIs were placed on NETs and Edemas, respectively. The ICVF, ISOVF, FA, and ADC values of NETs and Edemas differed significantly (p < 0.01). Receiver operating characteristic curve analysis revealed that using all parameters allowed for improved differentiation of NETs from Edemas (area under the curve = 0.918) from the use of NODDI parameters (0.910) or DTI parameters (0.899). Multiple logistic regression was performed with all parameters, and a predictive formula to differentiate between NETs and Edemas could be created and applied to the edematous regions of the negative control-group images; the tumor prediction degree was well below 0.5, confirming differentiation as edema. CONCLUSIONS: Using NODDI and DTI may prove useful in differentiating NETs from Edemas in the non-contrast T2 hyperintensity region of glioblastomas.

Nonbrain metastases seen on magnetic resonance imaging during metastatic brain tumor screening.

Although metastases found during head magnetic resonance imaging (MRI) are not limited to metastatic brain tumors, the MRI is a very common method for "brain metastasis screening," a modality that is being increasingly performed. In this review, we describe MRI findings of nonbrain metastases and discuss ways to avoid missing these lesions. Metastatic cranial bone tumors are among the most common nonbrain metastatic lesions found on head MRI, followed by leptomeningeal carcinomatosis. The other less-frequent metastatic lesions include those in the ventricle/choroid plexus, the pituitary gland and stalk, and the pineal gland. Metastases in the head and neck area, as well as cranial and intracranial lesions, should be carefully evaluated. Furthermore, direct geographical invasion, perineural spread, and double cancers should also be considered. While it is important to recognize these metastatic lesions on MRI, because they may necessitate a change in treatment strategy that could lead to an improvement in prognosis due to early introduction of therapy, nonbrain lesions should also be given greater attention, given the increasing survival of patients with cancer and advances in MRI technology, such as contrast-enhanced-3D T1-weighted imaging.