Expanded analysis of high-grade astrocytoma with piloid features identifies an epigenetically and clinically distinct subtype associated with neurofibromatosis type 1.

High-grade astrocytoma with piloid features (HGAP) is a recently recognized glioma type whose classification is dependent on its global epigenetic signature. HGAP is characterized by alterations in the mitogen-activated protein kinase (MAPK) pathway, often co-occurring with CDKN2A/B homozygous deletion and/or ATRX mutation. Experience with HGAP is limited and to better understand this tumor type, we evaluated an expanded cohort of patients (n = 144) with these tumors, as defined by DNA methylation array testing, with a subset additionally evaluated by next-generation sequencing (NGS). Among evaluable cases, we confirmed the high prevalence CDKN2A/B homozygous deletion, and/or ATRX mutations/loss in this tumor type, along with a subset showing NF1 alterations. Five of 93 (5.4%) cases sequenced harbored TP53 mutations and RNA fusion analysis identified a single tumor containing an NTRK2 gene fusion, neither of which have been previously reported in HGAP. Clustering analysis revealed the presence of three distinct HGAP subtypes (or groups = g) based on whole-genome DNA methylation patterns, which we provisionally designated as gNF1 (n = 18), g1 (n = 72), and g2 (n = 54) (median ages 43.5 years, 47 years, and 32 years, respectively). Subtype gNF1 is notable for enrichment with patients with Neurofibromatosis Type 1 (33.3%, p = 0.0008), confinement to the posterior fossa, hypermethylation in the NF1 enhancer region, a trend towards decreased progression-free survival (p = 0.0579), RNA processing pathway dysregulation, and elevated non-neoplastic glia and neuron cell content (p < 0.0001 and p < 0.0001, respectively). Overall, our expanded cohort broadens the genetic, epigenetic, and clinical phenotype of HGAP and provides evidence for distinct epigenetic subtypes in this tumor type.

Alpha-synuclein supports type 1 interferon signalling in neurons and brain tissue.

The protein alpha-synuclein is predominantly expressed in neurons and is associated with neurodegenerative diseases like Parkinson's disease and dementia with Lewy bodies. However, the normal function of alpha-synuclein in neurons is not clearly defined. We have previously shown that mice lacking alpha-synuclein expression exhibit markedly increased viral growth in the brain, increased mortality and increased neuronal cell death, implicating alpha-synuclein in the neuronal innate immune response. To investigate the mechanism of alpha-synuclein-induced immune responses to viral infections in the brain, we challenged alpha-synuclein knockout mice and human alpha-synuclein knockout dopaminergic neurons with RNA virus infection and discovered that alpha-synuclein is required for neuronal expression of interferon-stimulated genes. Furthermore, human alpha-synuclein knockout neurons treated with type 1 interferon failed to induce a broad range of interferon stimulated genes, implying that alpha-synuclein interacts with type 1 interferon signalling. We next found that alpha-synuclein accumulates in the nucleus of interferon-treated human neurons after interferon treatment and we demonstrated that interferon-mediated phosphorylation of STAT2 is dependent on alpha-synuclein expression in human neurons. Next, we found that activated STAT2 co-localizes with alpha-synuclein following type 1 interferon stimulation in neurons. Finally, we found that brain tissue from patients with viral encephalitis expresses increased levels of phospho-serine129 alpha-synuclein in neurons. Taken together, our results show that alpha-synuclein expression supports neuron-specific interferon responses by localizing to the nucleus, supporting STAT2 activation, co-localizing with phosphorylated STAT2 in neurons and supporting expression of interferon-stimulated genes. These data provide a novel mechanism that links interferon activation and alpha-synuclein function in neurons.

Genomic and epigenomic re-categorization of congenital glioblastoma and desmoplastic infantile ganglioglioma.

INTRODUCTION: The recently updated World Health Organization classification of central nervous system (CNS) tumors, 5th edition, (CNS5) reclassifies pediatric tumors according to their distinct molecular drivers, recognizing a new entity-infant-type hemispheric glioma (IHG). Defined by its unique epigenetic signature, and/or genomic fusions in ALK, ROS1, NTRK, or MET gene, IHG subsumes many cases previously classified as congenital glioblastoma (cGBM). Histologic features of IHG are still poorly defined with known overlap with a clinic radiologically similar entity-desmoplastic infantile ganglioglioma/astrocytoma (DIG). METHODS: We revisited our cohort of cGBMs and DIGs, now reclassifying them according to CNS5 and compared the clinical, radiologic, molecular and histologic features between the two. RESULTS: 3/6 cases of cGBM that underwent targeted NGS fusion mutation panel were positive for ALK fusions (involving MAP4, MZT2Bex2, and EML4 genes as fusion partners), and 1/6 showed GOPC:ROS1 fusion. Interestingly, GOPC:ROS1 fusion was also shared by 1/5 cases of histologically defined DIG. DNA methylation profiling using the Heidelberg classifier (v12.3) recategorized 2/5 DIG cases as IHG (including the case with ROS1 alteration). CONCLUSION: In conclusion, histology alone is insufficient to distinguish IHG from DIG, necessitating epigenomic and genomic testing for the diagnosis of early-life gliomas.

Unusual features of neurosarcoidosis: A 18-year retrospective.

BACKGROUND: Neurosarcoidosis (NS) is a challenging diagnosis for clinicians and pathologists. NS most often presents with leptomeningeal involvement where it mimics infectious or neoplastic meningitis, and in up to half of cases, systemic signs of sarcoidosis are lacking. Rare presentations include dural-based mass(es) (mimicking meningioma), hypothalamic/sellar-based lesions (mimicking pituitary adenoma), or as myelopathy (mimicking tumor or neurodegenerative condition). For pathologists, the morphological effects of prior therapy are not well documented. NS as an unsuspected cause of demise today is even less well known. METHODS: Search of departmental databases and personal files, 2004-2022, for NS cases, with focus on the subset with features of interest to pathologists. RESULTS: 22 cases were identified (8 M: 14F, 13-66 years), in 11 of which the CNS specimen represented first diagnosis of sarcoidosis. 20 were surgical and 2 were autopsy cases. Focus of the study revolved around 2 surgical cases with NS granulomas intimately admixed with tumor (1 meningoma, 1 gonadotroph pituitary adenoma/pituitary neuroendocrine tumor (PitNET). One surgical and one autopsy case each had decrease in lymphocytes and well-formed granulomas, with increased fibrosis and hemosiderin in post-treatment tissues. We speculate, but cannot prove, that this may be due to prior steroid therapy. Both autopsy cases were women (38, 43-years), both with cauda equina syndrome/ progressive weakness as first presentation, and extensive spinal cord/nerve root sarcoidosis at demise. First diagnosis of NS/sarcoidosis was at autopsy in the 38-year-old. CONCLUSIONS: Unusual features for pathologists are that NS can co-exist within benign tumors, prior therapy alters histological features, and even in the modern era, may be first diagnosed at autopsy.

Urothelial carcinoma metastases impacting the CNS: A 20-year retrospective series.

INTRODUCTION: Our group has a longstanding interest in metastases impacting the central nervous system (CNS), including spread from prostatic adenocarcinomas, thyroid carcinomas, and breast carcinomas, most of which metastasize to CNS sites at a later time after the primary tumor is well-known. However, one of the least frequent types of systemic malignancies to metastasize to brain or spine is urothelial carcinoma. Thus, few large studies from a single institution exist. Fewer still detail the interval between first diagnosis of primary tumor and CNS lesion, or whether a patient might have their first presentation of cancer in the brain or spine, thus prompting review of our 20-year experience. MATERIALS: Case identification via text word search of pathology databases from our adult and referral hospitals, 2002 to present. Demographic and clinical data were extracted from reports and the medical record. RESULTS: 15 cases, 11 male: 4 female, age range 37-82 years were identified. Nine had metastases to brain parenchyma, 5 to vertebral column impacting spinal cord, and 2 to skull, one of which had tumor extension into right parietal lobe. Strikingly, 5 of 15 patients had had their CNS-impacting metastasis as their first presentation of neoplastic disease. CONCLUSIONS: CNS metastasis of urothelial carcinoma is a rare occurrence; nevertheless, pathologists should include urothelial carcinoma in their differential diagnosis as a type of cancer that can first present with a CNS-impacting metastasis.

Histopathologic features of nasal glial heterotopia (nasal glioma).

PURPOSE: Nasal glioneuronal heterotopia (NGH) is an uncommon developmental abnormality of the nasal cavity or paranasal soft tissue. Few detailed histologic studies of NGH exist, and molecular analyses have not been performed to date. METHODS: We describe six cases of pediatric NGH and two representative encephaloceles encountered in our practice over the past 20 years. RESULTS: Two clinically distinct patient groups were noted, those with 1) intranasal nasal cavity mass (n = 3), or 2) extranasal cutaneous mass on the nose (n = 3, 1 on nasal apex, 2 on nasal bridge). Intranasal cases presented within the first week of life, whereas the extranasal NGH presented at ages of 4, 7, and 8 months. Resection was curative in 5/6 cases, with a single case showing local recurrence. Histologic examination showed a predominantly glial cell composition, with nests of GFAP-immunoreactive neuropil containing large, often multinucleated astrocytes. Neurons, although difficult to identify on H&E-stains, were readily observed in all cases by NeuN-immunostain. At least focal leptomeninges were noted in 2/3 intranasal and 1/3 extranasal NGHs on routine histology, SSTR2A immunohistochemistry further confirmed leptomeninges/ arachnoid cells in 4/6 cases. 1 of 4 NGH (extranasal) cases showed copy number variations in chromosome 16, 17 and 19, which were also present in 1/2 encephalocele cases. The full significance of these alterations remains unknown. CONCLUSION: We find evidence of histologic overlap between NGH and encephalocele, and, for the first time, report molecular alterations shared between the two entities, suggesting that these conditions may represent spectrum of the same histopathologic entity.

Innumerable Meningiomas Arising in a Patient With Tuberous Sclerosis Complex Decades After Radiation Therapy.

Meningioma is the most common radiation-induced brain neoplasm, usually occurring after a latency of 20 - 35 years, with multiplicity in 10% of cases. Radiation-induced meningiomas (RIMs) have not previously been reported in patients with tuberous sclerosis complex (TSC), unlike their well-known occurrence in other familial tumor predisposition syndrome patients. We report a TSC patient who developed numerous intracranial meningiomas twenty five year after radiation therapy for subependymal giant cell astrocytoma (SEGA). Autopsy examination showed innumerable, coalescent, benign, meningothelial meningiomas, WHO grade 1, ranging in size from 0.2 cm to 3.3 cm. Autopsy also showed small residual SEGA, radiation-induced cerebral vasculopathy, and classic TSC features including several small subependymal nodules ("candle gutterings"), white matter radial heterotopia, facial angiofibromas, dental enamel pitting, one ash leaf spot, and multiple hepatic and renal angiomyolipomas. Next-generation sequencing analysis utilizing a 500+ gene cancer panel demonstrated chromosomal loss involving the majority of chromosome 22, including the NF2 gene locus, as well as a truncating nonsense mutation in TSC1 p. R509*. While TSC patients rarely require radiation therapy, this striking case suggests that patients with TSC should be monitored closely if cranial therapeutic radiation is administered.

Secondary parenchymal CNS involvement by lymphoma including rare types: Follicular and EBV-positive NK/T cell lymphoma, nasal type.

BACKGROUND: Secondary CNS involvement by systemic lymphomas (SCNSL) is uncommon, but when it occurs, is usually due to diffuse large B cell lymphoma (DLBCL). Three recent unusual cases serve to highlight diagnostic challenges. OBJECTIVE: To report SCNSL from DLBCL and two unusual lymphoma types: follicular lymphoma with high-grade transformation to DLBCL and NK/T cell lymphoma, nasal type (ENKL), nasal type. RESULTS: SCNSL in the DLBCL case occurred at 7-year interval from primary in a 54-year-old woman who presented with stroke-like symptoms and a right postcentral gyrus 2.6 × 2.9 × 2.6 cm. mass. The follicular lymphoma occurred at 6-month interval in a 69-year-old woman with 1 month of diplopia and 2 weeks of cognitive decline; multifocal lesions involved temporal lobe, subependymal periventricular areas, brainstem, cerebellum, hypothalamus, corpus callosum and gyrus rectus. The ENKL occurred at 25-month interval from nasal biopsy in a 45-year-old man with 1 week of altered mental status; multifocal cerebral and brainstem lesions were identified. Histological features in cases 1 and 3 were identical to the primary lymphoma, with high-grade transformation to DLBCL in the follicular lymphoma. CONCLUSION: Unusual features in our series include longer interval from primary to relapse in case 1 with DLBCL (usually <2 years of diagnosis), and SCNSL occurring from either follicular lymphoma or EKNL, nasal type (<6% of cases). Pathologists play an important role in excluding infectious, especially in cases with parenchymal lesions and characterizing the lymphoma type in SCNSL.

Targetable molecular alterations in congenital glioblastoma.

INTRODUCTION: Congenital glioblastomas (cGBMs) are uncommon tumors presenting in early infancy, variably defined as diagnosed at birth or at age less than 3 months by strict criteria, or more loosely, as occurring in very young children less than 12 months of age. Previous studies have shown that cGBMs are histologically indistinguishable from GBMs in older children or adults, but may have a more favorable clinical outcome, suggesting biological differences between congenital versus other GBMs. Due to the infrequency of cGBMs, especially when employing strict inclusion criteria, molecular features have not been sufficiently explored. METHODS: Archer FusionPlex Solid Tumor Kit, Archer VariantPlex Solid Tumor Kit, Illumina RNAseq were utilized to study cGBMs seen at our institution since 2002. A strict definition for cGBM was utilized, with only infants less than age 3 months at clinical presentation sought for this study. RESULTS: Of the 8 cGBM cases identified in our files, 7 had sufficient materials for molecular analyses, and 3 of 7 cases analyzed showed fusions of the ALK gene (involving MAP4, MZT2Bex2 and EML4 genes as fusion partners). One case showed ROS1 fusion. Somatic mutations in TSC22D1, BMG1 and DGCR6 were identified in 1 case. None of the cases showed alterations in IDH1/2, histone genes, or the TERT gene, alterations which can be associated with GBMs in older children or adults. CONCLUSIONS: Our results show that cGBMs are genetically heterogeneous and biologically different from pediatric and adult GBMs. Identification of ALK and ROS1 raise the possibility of targeted therapy with FDA-approved targeted inhibitors.

Prostatic adenocarcinoma CNS parenchymal and dural metastases: alterations in ERG, CHD1 and MAP3K7 expression.

BACKGROUND: Prostatic carcinoma metastatic to dura is commonly encountered at autopsy, but presenting as a dural or, especially parenchymal, brain metastasis during life is far less common. Our group has been interested in two immunohistochemical (IHC) markers previously shown to be downregulated in particularly aggressive primary prostatic carcinomas: CHD1 and MAP3K7. Here we assess protein expression in clinically-relevant CNS metastases. We also assessed how these two markers correlated with the most common genetic alteration in prostate cancer: TMPRSS2 fusion to ERG (40-60% of carcinomas at the primary site), which places ERG expression under the control of the androgen-regulated TMPRSS2 gene, increasing expression. DESIGN: Database query, 2000-2016, identified 16 metastases to dura, 5 to brain parenchyma. RESULTS: Four of five intraparenchymal metastases and 15/16 informative dural-based metastases were ERG-negative (90.5% overall). There was reduced expression of CHD1 in 8/21 and reduced MAP3K7 in 17/21 cases; 7/19 (37%) ERG-negative metastases had dual low expression of CHD1/MAP3K7. ERG-positive cases had high expression of one or both markers. CONCLUSION: Metastatic prostatic carcinoma to CNS demonstrates expression patterns consistent with particularly aggressive behavior. Lower ERG expression in dural and intraparenchymal metastases suggests a possibility that ERG-negative tumors with loss of MAP3K7 may become resistant to standard therapies and diffusely metastasize.

Neuropathological Findings in a Case of IFIH1-Related Aicardi-Goutières Syndrome.

Aicardi-Goutières syndrome (AGS) is a rare syndrome characterized by calcification, diffuse demyelination, and variable degree of brain atrophy. The syndrome is genetically heterogeneous with mutations in 7 genes, including TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR1, and IFIH1 (interferon-induced helicase c domain-containing protein 1) associated with the syndrome, so far. These mutations lead to the overproduction of α-interferon within the central nervous system. Mutations in IFIH1 have been recently described in a subset of AGS, with only 1 previous report of neuropathological findings. We report neuropathological findings in a second case of AGS with a known mutation in IFIH1 gene. The patient is a 16-year-old adolescent boy with early-onset symptoms that progressed to profound loss of cognitive and motor functions. The patient experienced sudden cardiopulmonary arrest at the age of 16 years. At autopsy, the cause of death was determined to be pulmonary thromboembolism. Neuropathological examination revealed microcephaly (brain weight: 916 g) with relatively mild brain atrophy on gross examination. Microscopic examination revealed multifocal calcifications limited to small to medium central nervous system arteries (no evidence of calcification in other organs), involving bilateral cerebral cortex, basal ganglia, thalamus, and cerebellum. Ultrastructural examination showed Calcospherules limited to the vessel walls and the perivasulcar area without evidence of neuronal ferrugination or tubuloreticular bodies. The extent of calcifications was variable across different brain regions, resembling findings in previously reported cases and correlated with the extent of IFIH1 protein expression (data derived from Allen Brain Institute). AGS is a rare cause of brain calcifications that can closely mimic congenital and neonatal infections such as Rubella and similar infections.

Intracranial Ewing sarcoma: four pediatric examples.

BACKGROUND: Ewing sarcoma typically arises in bone and is unrelated to intraparenchymal small blue cell embryonal central nervous system (CNS) tumors previously designated primitive neuroectodermal tumors (PNETs). When the CNS is impacted, it is usually secondary to local extension from either the epidural space, skull, or intracranial or spinal metastases. Primary examples within the cranial vault are rare, usually dural-based, and are largely case reports in the literature. We detail four pediatric patients with solitary, primary intracranial Ewing sarcoma, all manifesting the archetypal EWRS1 gene rearrangement that confirms diagnosis. PROCEDURE: Neurosurgical Department records, spanning 21 years (1995-2016), were reviewed to identify patients. Demographics, clinical history, pathological/genetic features, and clinical course were retrieved from the medical record and personal files of the authors. RESULTS: Four patients, one male and three females, age 5 to 16 years, were identified. One presented in extremis from a large lesion, two with soft tissue masses, and the fourth as an incidental finding after being involved in a motor vehicle collision. Three had clear bony involvement: a 10-year-old girl with a large left temporal lesion had clear origin in the skull, with spiculated calcified striations throughout the mass; a 9-year-old girl presented with a bony left petrous apex mass; and a 16-year-old girl presented with a left temporal mass with extension to the dura and underlying bone erosion. Only the 5-year-old boy had a large left frontoparietal mass traversing the falx with no bony contact. All four tumors manifested the diagnostic EWSR1 mutation and were treated with an Ewing sarcoma regimen. Outcomes were variable, with one patient showing progressive metastatic disease and death 3 years after presentation, one patient with disease-free survival 10.5 years after completion of therapy, and one alive and well at the completion of therapy 1 year after diagnosis. One patient completed therapy recently with post-therapy scans showing no evidence of disease. CONCLUSION: Testing for the EWSR1 mutation confirms the diagnosis of Ewing sarcoma and excludes other types of embryonal CNS tumors. Long-term disease-free survival is possible with adherence to the appropriate therapeutic regimen after gross surgical resection.

Desmoplastic infantile astrocytoma/ganglioglioma with rare BRAF V600D mutation.

BACKGROUND: Desmoplastic infantile astrocytoma (DIA) and desmoplastic infantile gangliogliomas (DIGs) are rare, massive, cystic and solid tumors of infants usually found in superficial cerebral hemispheres. They manifest prominent desmoplastic stroma, admixed neoplastic astrocytes, primitive-appearing small cells, and additional neoplastic ganglion cells in the case of DIGs. While v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutation is found in up to 50% of pediatric gangliogliomas, two recent studies found that it was rare in DIA/DIGs; we sought to assess BRAF status in DIA/DIGs from our institution. PROCEDURE: Departmental files from 2000 to 2016 were reviewed to identify cases. Clinical, neuroimaging, histological, and immunohistochemistry (IHC) features were assessed; the latter included IHC for astrocytic and neuronal markers and BRAF VE1. BRAF mutational assessment by Sanger and next-generation sequencing was attempted in all cases. RESULTS: All six identified cases (four males-two females; three DIA-three DIG) occurred in children <1-year old, were large, cerebral-hemispheric, cystic and solid, and enhancing tumors. Only one case, a DIG with prominent aggregates of neoplastic ganglion cells, showed either BRAF VE1 IHC positivity or mutation by Sanger and next-generation sequencing (rare c. 1799_1800delinsAT; p. V600D). Four of six archival cases were BRAF VE1 IHC negative, but failed mutational sequencing. CONCLUSION: Five of six classic DIA/DIGs were negative for BRAF mutation; previous series have identified BRAF mutation in two of 18 and one of 14 cases, although all were the more common BRAF V600E. We were unable to find other examples of glial tumors in public databases with this rare BRAF V600D mutation. Identification of BRAF mutational opens the possibility of BRAF-targeted therapies for the subset of DIA/DIG that clinically progress postresection.

p16 Loss and E2F/cell cycle deregulation in infant posterior fossa ependymoma.

BACKGROUND: Posterior fossa (PF) ependymomas (EPNs) in infants less than 1 year of age (iEPN-PF) have a poorer clinical outcome than EPNs in older children. While radiation therapy is the standard of care for the latter, it is withheld in infants to avoid neurotoxicity to immature brain. It is unknown whether the adverse outcome in iEPN-PFs is due to treatment differences or aggressive biology. We examined this question using molecular profiling. METHODS: Six anaplastic iEPN-PFs were subjected to transcriptomic analysis and FISH for p16 loss and gains of 1q, and compared with anaplastic PF EPNs from older children. Results were validated by immunohistochemistry (IHC). RESULTS: All six iEPN-PFs were grouped within EPN PF subgroup A (PFA). E2F targets and G2M checkpoint were identified as the most enriched gene sets in iEPN-PF, which was validated in a larger independent cohort. Accordingly, MIB-1 IHC demonstrated a higher mitotic rate in iEPN-PFs than noninfant anaplastic EPN PFA. Genetic and protein analyses demonstrated that p16 loss and low p16 protein expression is a hallmark of iEPN-PF, and that none harbored 1q gains. Kaplan-Meier analysis confirmed the poorer clinical outcome of the iEPN-PF cohort. CONCLUSIONS: Biological differences, characterized by loss of p16 expression without gains of 1q in iEPN-PFs, as well as deregulated E2F target gene transcription, are indicative of deregulated p16-CDK4/6-pRB-E2F pathway activity. This may underlie the poor clinical outcome seen in this group of iEPN-PFs, rather than the withholding of radiation therapy. Results suggest a potential actionable therapy for iEPN-PF, namely cyclin-dependent kinase 4/6 (CDK4/6) inhibitors.

Double separate versus contiguous pituitary adenomas: MRI features and endocrinological follow up.

PURPOSE: Double pituitary adenomas are defined as two adenomas within a gland. These have distinct light microscopic and immunohistochemical features and may be clearly-separate or contiguous. Most reports have focused on the various hormonal combinations in double tumors rather than on any potential increased risk for residual mass or endocrinopathy. METHODS: Departmental files were searched to identify all double adenomas from 1/1/2000 to 3/1/2016, with review of magnetic resonance imaging (MRI) to determine if the dual nature of the lesions could be discerned retrospectively after histologic diagnosis of double adenoma. All cases were immunostained for standard anterior pituitary hormones. RESULTS: Eight cases were identified: 2 follicle-stimulating hormone (FSH)/alpha subunit (ASU) + prolactinoma (PRL); 1 PRL + corticotroph (ACTH); 1 hormone-negative + PRL; 1 ACTH + ASU/growth hormone (GH)/PRL; 1 GH/PR + PRL; 1 FSH/ASU, + ACTH; 1 GH + luteinizing hormone (LH). One patient had clearly-separate lesions identified preoperatively and required two surgical procedures for gross total resection. A second patient had 2 lesions recognized at surgery and afterwards on retrospective neuroimaging. The remaining 6 patients had double adenomas discovered at the time of histologic examination that were not resolvable at surgery or on retrospective neuroimaging. Four patients, 2 with clearly-separate and 2 with contiguous double adenomas, had persistent MRI abnormalities, and one had continued endocrine abnormalities. CONCLUSIONS: Double contiguous pituitary adenomas are difficult to anticipate preoperatively or to resolve intraoperatively. Although double contiguous adenomas are much more common than double separate lesions, both have a risk for subtotal resection and, thus, residual mass and/or endocrinopathy may ensue.

Phase II trial of hypofractionated intensity-modulated radiation therapy combined with temozolomide and bevacizumab for patients with newly diagnosed glioblastoma.

Bevacizumab blocks the effects of VEGF and may allow for more aggressive radiotherapy schedules. We evaluated the efficacy and toxicity of hypofractionated intensity-modulated radiation therapy with concurrent and adjuvant temozolomide and bevacizumab in patients with newly diagnosed glioblastoma. Patients with newly diagnosed glioblastoma were treated with hypofractionated intensity modulated radiation therapy to the surgical cavity and residual tumor with a 1 cm margin (PTV1) to 60 Gy and to the T2 abnormality with a 1 cm margin (PTV2) to 30 Gy in 10 daily fractions over 2 weeks. Concurrent temozolomide (75 mg/m(2) daily) and bevacizumab (10 mg/kg) was administered followed by adjuvant temozolomide (200 mg/m(2)) on a standard 5/28 day cycle and bevacizumab (10 mg/kg) every 2 weeks for 6 months. Thirty newly diagnosed patients were treated on study. Median PTV1 volume was 131.1 cm(3) and the median PTV2 volume was 342.6 cm(3). Six-month progression-free survival (PFS) was 90 %, with median follow-up of 15.9 months. The median PFS was 14.3 months, with a median overall survival (OS) of 16.3 months. Grade 4 hematologic toxicity included neutropenia (10 %) and thrombocytopenia (17 %). Grades 3/4 non-hematologic toxicity included fatigue (13 %), wound dehiscence (7 %) and stroke, pulmonary embolism and nausea each in 1 patient. Presumed radiation necrosis with clinical decline was seen in 50 % of patients, two with autopsy documentation. The study was closed early to accrual due to this finding. This study demonstrated 90 % 6-month PFS and OS comparable to historic data in patients receiving standard treatment. Bevacizumab did not prevent radiation necrosis associated with this hypofractionated radiation regimen and large PTV volumes may have contributed to high rates of presumed radiation necrosis.

Orbital invasion by ACTH-secreting pituitary adenomas.

Orbital invasion by pituitary tumors is rare. To the best of the authors' knowledge, adrenocorticotrophin (ACTH)-secreting pituitary tumors with orbital invasion have not been described in MEDLINE indexed literature. The authors report 2 cases of ACTH-secreting tumors with orbital invasion. One patient had a history of endoscopic transsphenoidal subtotal resection of an ACTH-secreting tumor and presented with recurrence in the orbit. The second patient had a long history of visual loss considered to be secondary to glaucoma. Neuroimaging revealed a destructive mass involving the sella turcica with extension in the right orbit. Debulking of the mass was performed via a transsphenoidal approach, and histopathology revealed an ACTH-secreting adenoma. ACTH-secreting adenoma should be considered in the differential of tumors involving the sella turcica with orbital invasion.

Reassessment of Plurihormonal Pituitary Adenomas/PitNETs.

Plurihormonal pituitary adenomas/neuroendocrine tumors express multiple pituitary hormones and/or transcription factors, as determined by immunohistochemistry (IHC). Three types exist based on Endocrine WHO 2022 classification: mature plurihormonal PIT1 (pituitary-specific POU-class homeodomain factor-1), immature PIT1-lineage tumors, and a third type with unusual combinations of pituitary hormones and/or transcription factors. However, since then, "somatogonatotroph"/"multilineage" tumors with PIT1/SF1 (steroidogenic factor 1) co-expression have been described, possibly confounding this classification. We performed a database search, from 2018 to 2023, to identify and reclassify tumors, correlating with neuroimaging and endocrinological features at presentation. We identified 22 cases: M 9:F 13, mean age at surgery 51±16 years. The most common symptoms at initial presentation were headaches and/or vision changes (6/22) and acromegaly (5/22). All tumors were macroadenomas, mean diameter of 25±17mm; 11/22 (50%) had cavernous sinus invasion. More than 70% of tumors clinically secreted at least 1 hormone, and 27% tumors secreted at least 2 different hormones. Four patients underwent >1 surgical intervention. Reclassification by IHC yielded almost exclusively 2 types: immature PIT1-lineage (9/22) and "somatogonadotroph"/"multilineage tumors" with PIT1/SF1 co-expression (12/22), the latter replacing mature plurihormonal tumors. One true unusual plurihormonal tumor was identified. The extent of growth hormone, prolactin, thyroid stimulating hormone, PIT1, and SF1 IHC was variable, but immunopositivity for follicle-stimulating hormone and/or luteinizing hormone was nearly confined to co-expressors, distinguishing these from immature PIT1-lineage tumors. In conclusion, tumor size, invasiveness, and endocrinopathies do not distinguish PIT1/SF1 co-expressing tumors from immature PIT1-lineage tumors preoperatively; only full IHC pituitary workup allows distinction.

Pituitary Adenoma Coexistent with Sellar Clear Cell Meningioma Unattached to the Dura: Case Report and Treatment Considerations.

Collision tumors involving the sella are rare. Intrasellar collision tumors are most commonly composed of a combination of pituitary adenomas and pituitary neuroendocrine tumors; however, collision tumors consisting of a pituitary adenoma and intrasellar meningioma are exceedingly rare. The authors present the case of a 47-year-old man who presented with progressive right eye vision loss. Magnetic resonance imaging showed a large, heterogeneously enhancing sellar mass with suprasellar extension. Using a transcranial approach with a right subfrontal craniotomy, near-total resection of the mass was achieved. Histologic analysis confirmed a diagnosis of a gonadotroph adenoma with concomitant clear cell meningioma (CCM). This patient was discharged with improvement in visual acuity and no signs of diabetes insipidus. Given the indistinguishable radiographic characteristics of pituitary adenoma and CCM, a preoperative diagnosis of a collision tumor was difficult. This case was uniquely challenging since the CCM component lacked the classic dural attachment that is associated with meningiomas on neuroimaging. CCMs are classified as central nervous system (CNS) World Health Organization (WHO) grade 2 tumors and tend to behave more aggressively, therefore warranting close surveillance for signs of tumor recurrence. This is the first case to report a collision tumor consisting of pituitary adenoma and CCM.