Background

Subtypes of glioblastoma multiforme (GBM) based on genetic and molecular alterations are thought to cause alterations in anatomic MRI owing to downstream biological changes, such as edema production, blood-brain barrier breakdown, and necrosis. The purpose of the current study was to identify a potential relationship between imaging features and the mesenchymal (MES) GBM subtype, which has the worst patient prognosis.

Methods

MRIs from 46 patients with histologically confirmed GBM were retrospectively analyzed. The volume of contrast enhancement, regions of central necrosis, and hyperintensity of T2/fluid attenuated inversion recovery (FLAIR) were measured. Additionally, the ratio of T2/FLAIR hyperintense volume to the volume of contrast enhancement and necrosis was calculated.

Results

The volume of contrast enhancement, volume of central necrosis, combined volume of contrast enhancement and central necrosis, and the ratio of T2/FLAIR to contrast enhancement and necrosis were significantly different in MES compared with non-MES GBM (Mann-Whitney, P < .05). Receiver-operator characteristics indicated that these 4 metrics were all significant predictors of the MES phenotype. The volume ratio of T2 hyperintensity to contrast enhancement and central necrosis was significantly lower in MES vs non-MES GBM (P < .0001), was a significant predictor of the MES phenotype (area under the curve = 0.93, P < .001), and could be used to stratify short- and long-term overall survival (log-rank, P = .0064 using cutoff of 3.0). These trends were also present when excluding isocitrate dehydrogenase 1 mutant tumors and incorporating covariates such as age and KPS score.

Conclusions

Results suggest that volume ratio may be a simple, cost-effective, and noninvasive biomarker for quickly identifying MES GBM.

Background

Information regarding clinical signs, assessment, treatment, and outcome in cats with hiatal hernia (HH) is limited.

Objectives

To characterize the clinical presentation of HH and medical and surgical outcomes in a cohort of affected cats.

Animals

Thirty-one client-owned cats with HH.

Methods

Medical records of cats with HH were retrospectively reviewed for signalment, history, results of diagnostic tests, details of surgical and medical treatments, complications, and outcome. Long-term follow-up data were obtained by telephone communication. Relationships between clinical variables and outcome were evaluated by regression analysis.

Results

Type I HH was present in 85.7% (24/28) of cats, and 64.5% (20/31) were >3 years of age at diagnosis. Twenty-one of 31 (67.7%) cats underwent surgical repair including phrenoplasty, esophagopexy, and left-sided gastropexy, and 10 of 31 cats were treated medically without surgery. Concurrent illness was common, and 77.4% cats had comorbidities. All cats survived to discharge, and median time to death or follow-up was 959 days (range, 3-4015 days). Cats treated medically survived longer than cats treated surgically, with median time to death or follow-up of 2559 and 771 days, respectively.

Conclusions and clinical importance

Type I HH is the most common type of HH in cats. A congenital etiology is possible, but many cats with HH were >3 years of age at diagnosis and suffered from comorbidities, including upper airway obstruction. Case selection and the presence of comorbidities likely influenced the outcome. Cats with HH may not be diagnosed until disease is advanced or concurrent illness draws attention to clinical signs.

Background

Limited information currently exists regarding the clinical progression and outcomes of cats that undergo choledochal stenting as a treatment for extrahepatic biliary obstruction (EHBO).

Hypothesis/objectives

Describe clinical characteristics, indications for choledochal stent placement, procedure, and outcomes in a cohort of cats undergoing choledochal stenting and evaluate risk factors associated with survival as well as recurrence of EHBO in affected cats.

Animals

Twenty-three client-owned cats undergoing choledochal stent placement.

Methods

Retrospective study. Medical records from 6 academic institutions were reviewed, and data were extracted and analyzed statistically.

Results

Median age of cats was 10.1 years (range, 2-16), and all cats had at least 2 clinical signs. Most common clinical signs were vomiting in 20/22 (90.9%), inappetence in 19/22 (86.4%), and lethargy in 19/23 (82.6%). Procedural complications were uncommon and rarely related to the stenting procedure. Clinical signs improved postoperatively in 15/20 (75.0%) cats and serum total bilirubin concentration decreased postoperatively in 13/19 (68.4%) cats. Eighteen (78.3%) cats survived to discharge. Recurrence of EHBO was documented in 7/18 (38.9%) cats that survived to discharge. Cholelithiasis was associated with recurrence of EHBO. Median survival time for cats that survived to discharge was 931 days (range, 19-3034). Absence of peritoneal effusion was associated with survival to discharge.

Conclusions and clinical importance

Choledochal stenting was an effective treatment modality in cats with EHBO with few procedural complications and potential for prolonged survival, but substantial risk for recurrence of EHBO was identified.

Promoter methylation of O6-methylguanine DNA methyltransferase (MGMT) is associated with a favorable prognosis in glioblastoma multiforme (GBM) and has been hypothesized to occur early in tumor transformation of glial cells. Thus, a possible link exists between the site of malignant transformation and MGMT promoter methylation status. Using the Analysis of Differential Involvement (ADIFFI) statistical mapping technique in a total of 358 patients with GBM, we demonstrate that human de novo GBMs occur in a high frequency contiguous with the posterior subventricular zone (SVZ); MGMT promoter methylated GBMs are lateralized to the left hemisphere, while MGMT unmethylated GBMs are lateralized to the right hemisphere; and tumors near the left temporal lobe have a significantly longer overall survival compared with tumors occurring elsewhere, independent of treatment or MGMT methylation status.

Background

Information regarding clinical signs, assessment, treatment, and outcome in cats with hiatal hernia (HH) is limited.

Objectives

To characterize the clinical presentation of HH and medical and surgical outcomes in a cohort of affected cats.

Animals

Thirty-one client-owned cats with HH.

Methods

Medical records of cats with HH were retrospectively reviewed for signalment, history, results of diagnostic tests, details of surgical and medical treatments, complications, and outcome. Long-term follow-up data were obtained by telephone communication. Relationships between clinical variables and outcome were evaluated by regression analysis.

Results

Type I HH was present in 85.7% (24/28) of cats, and 64.5% (20/31) were >3 years of age at diagnosis. Twenty-one of 31 (67.7%) cats underwent surgical repair including phrenoplasty, esophagopexy, and left-sided gastropexy, and 10 of 31 cats were treated medically without surgery. Concurrent illness was common, and 77.4% cats had comorbidities. All cats survived to discharge, and median time to death or follow-up was 959 days (range, 3-4015 days). Cats treated medically survived longer than cats treated surgically, with median time to death or follow-up of 2559 and 771 days, respectively.

Conclusions and clinical importance

Type I HH is the most common type of HH in cats. A congenital etiology is possible, but many cats with HH were >3 years of age at diagnosis and suffered from comorbidities, including upper airway obstruction. Case selection and the presence of comorbidities likely influenced the outcome. Cats with HH may not be diagnosed until disease is advanced or concurrent illness draws attention to clinical signs.

High-grade astrocytomas (HGAs), corresponding to World Health Organization grades III (anaplastic astrocytoma) and IV (glioblastoma; GBM), are biologically aggressive, and their molecular classification is increasingly relevant to clinical management. PDGFRA amplification is common in HGAs, although its prognostic significance remains unclear. Using fluorescence in situ hybridization (FISH), the most sensitive technique for detecting PDGFRA copy number gains, we determined PDGFRA amplification status in 123 pediatric and 263 adult HGAs. A range of PDGFRA FISH patterns were identified and cases were scored as non-amplified (normal and polysomy) or amplified (low-level and high-level). PDGFRA amplification was frequent in pediatric (29.3%) and adult (20.9%) tumors. Amplification was not prognostic in pediatric HGAs. In adult tumors diagnosed initially as GBM, the presence of combined PDGFRA amplification and isocitrate dehydrogenase 1 (IDH1)(R132H) mutation was a significant independent prognostic factor (P = 0.01). In HGAs, PDGFRA amplification is common and can manifest as high-level and focal or low-level amplifications. Our data indicate that the latter is more prevalent than previously reported with copy number averaging techniques. To our knowledge, this is the largest survey of PDGFRA status in adult and pediatric HGAs and suggests PDGFRA amplification increases with grade and is associated with a less favorable prognosis in IDH1 mutant de novo GBMs.

The kynurenine pathway (KP) is the principal route of L-Tryptophan (TRP) catabolism leading to the production of kynurenine (KYN), the neuroprotectants, kynurenic acid (KYNA) and picolinic acid (PIC), and the excitotoxic neurotoxin, quinolinic acid (QUIN). The enzymes indoleamine 2,3-dioxygenase-1 (IDO-1), indoleamine 2, 3-dioxygenase-2 (IDO-2) and tryptophan 2,3-dioxygenase (TDO-2) initiate the first step of the KP. Downstream enzymes include kynureninase (KYNU), 3-hydroxyanthranilate 3,4-dioxygenase (3-HAAO), kynurenine hydroxylase (KMO) and 2-amino-3-carboxymuconate semialdehyde decarboxylase (ACMSD). Kynurenine aminotransferase-I (KAT-I) is one of the enzymes responsible for synthesising KYNA. Mounting evidence directly implicates that IDO-1 induction in various tumours is a crucial mechanism facilitating tumour immune evasion and persistence. However, the involvement of the downstream machinery of the KP in brain tumour progression remains unexplored. A complete characterisation of the KP in brain tumours and the role of the KP in maintaining homeostasis between neuroprotection and neurodegeneration in glioma has not yet been investigated. Here we report the first comprehensive characterisation of the KP in cultured human glioma cells and GBM patient plasma. Our qRT-PCR data revealed that interferon-gamma (IFN-γ) (100 IU/ml) stimulation significantly potentiated the expression of IDO-1 IDO-2, KYNU, 3-HAAO, KMO and significantly down-regulated ACMSD and KAT-I expression in cultured human glioma cells. HPLC analysis revealed that IFN-γ stimulation significantly increased KP activity (KYN/TRP ratio), and significantly lowered the KYNA/KYN neuroprotective ratio in human cultured glioma cells. Our HPLC and GCMS data revealed that KP activation was significantly higher and the concentrations of TRP, KYNA, QUIN and PIC and the KYNA/KYN ratio were significantly lower in GBM patient plasma (n = 18) compared to controls. These results provide further evidence for the involvement of the KP in glioma pathophysiology and highlights a potential role of KP products as novel and highly attractive therapeutic targets to evaluate for the treatment of brain tumours.