Revised Diagnosis From Histiocytic Neoplasm to Optic Chiasm Glioblastoma After Genetic Analysis.

ABSTRACT: A 46-year-old man presented with left eye blurring. Automated visual field testing showed an incongruous right hemianopia, with sparing of the lower temporal quadrant in the right eye. MRI revealed foci of gadolinium enhancement in the optic chiasm and optic tracts. Serologic testing (including myelin oligodendrocyte glycoprotein and neuromyelitis optica antibodies) and cerebrospinal fluid analysis were negative. Whole-body PET/CT scan found no malignancy. Biopsy of the optic chiasm revealed a moderately cellular neoplasm composed of atypical, discohesive cells with enlarged nuclei, prominent eosinophilic nucleoli, and abundant vacuolated cytoplasm. Immunohistochemical stains for CD68 and S100 were positive, whereas those for GFAP, OLIG2, SOX10, and multiple others were negative, supporting a diagnosis of histiocytic neoplasm. Five weeks later, results became available from next-generation sequencing targeting the coding regions of hundreds of malignancy-associated genes and select introns. Alterations associated with histiocytic neoplasms (i.e. BRAF and MAP2K1 mutations) were absent. However, there was a nonsense mutation in the PTEN gene, a hotspot mutation in the TERT gene promotor, and focal amplifications of the CDK4 and MDM2 genes. Additionally, there was chromosome 6q loss, 7 gain, and 10q loss. Based on these findings, the diagnosis was revised to glioblastoma, IDH-wildtype, CNS WHO grade 4. The patient began treatment with temozolomide while continuing radiation therapy. This case illustrates how next-generation sequencing can at times provide more accurate diagnostic information than standard tissue histopathology.

Utility of PD-1, PD-L1, and IDO-1 Stains in Ocular Extranodal Marginal Zone Lymphoma (MZL) and Diffuse Large B-cell Lymphoma (DLBCL).

Extranodal marginal zone lymphoma (EMZL) is the most common subtype of ocular lymphomas. Diffuse large B-cell lymphoma (DLBCL) and EMZL with large-cell transformation present diagnostic challenges. Radiotherapy is the standard treatment for ocular lymphomas, but complications and relapse are common. Diagnostic utility in challenging cases, as well as treatment options using immune checkpoint inhibitors, are unclear in ocular lymphomas. We herein investigated the PD-1, PD-L1, and IDO1 staining patterns in 20 cases of ocular lymphomas, including EMZL (n=14), EMZL with increased large cells (n=2), and DLBCL (n=4). PD-1, PD-L1, and IDO1 staining was not detected in lymphoma cells in any cases but was observed within the tumor microenvironment in all cases. Positivity for PD-1, PD-L1, and IDO1 in inflammatory cells was seen either intratumorally or peritumorally. In all 6 cases with significantly more large B cells, the density of PD-1, PD-L1, and IDO1 expression in the tumor microenvironment was higher than that of the remaining 14 cases without large B cells (P-value<0.0001), whereas other clinicopathologic features showed no statistical correlation. Increased expression of PD-1, PD-L1, and IDO1 in the inflammatory milieu in cases with large cells may provide diagnostic utility in small biopsies as well as therapeutic potential.

Metastatic glioblastoma to the lungs: a case report and literature review.

Glioblastoma is the most common malignant primary brain tumor. Despite its infiltrative nature, extra-cranial glioblastoma metastases are rare. We present a case of a 63-year-old woman with metastatic glioblastoma in the lungs. Sarcomatous histology, a reported risk factor for disseminated disease, was found. Genomic alterations of TP53 mutation, TERT mutation, PTEN mutation, and +7/-10 were also uncovered. Early evidence suggests these molecular aberrations are common in metastatic glioblastoma. Treatment with third-line lenvatinib resulted in a mixed response. This case contributes to the growing body of evidence for the role of genomic alterations in predictive risk in metastatic glioblastoma. There remains an unmet need for treatment of metastatic glioblastoma.

Glioblastoma is the most common malignant primary brain tumor. Glioblastoma can spread into healthy tissue, but metastases beyond the brain are rare. We present a case of a 63-year-old woman with metastatic glioblastoma in the lungs. We identified risk factors associated with spread beyond the brain, including factors related to tissue structure and specific molecular alterations. Treatment with third-line lenvatinib resulted in a mixed response. This case adds to the limited existing data for the use of molecular alterations to serve as risk factors for metastatic glioblastoma. Treatment options are needed for this devastating disease.

Pembrolizumab in an HIV-infected patient with glioblastoma.

Persons living with human immunodeficiency virus (PLWH) carry increased risk for developing malignancies, including glioblastoma. Despite extensive investigations, both human immunodeficiency virus (HIV) and glioblastoma are incurable. Treatment for a patient with combined glioblastoma and HIV remains an unexplored need. Preliminary evidence suggests that immunotherapy may be effective for the simultaneous treatment of both HIV and cancer by reversing HIV latency and T cell exhaustion. We present a case of glioblastoma in a PLWH who was treated with pembrolizumab. Treatment was well tolerated and safe with a mixed response. Our patient did not develop any opportunistic infections, immune-related adverse events, or worsening of his immunodeficiency. To our knowledge, this is the first reported case of a PLWH and glioblastoma treated with immunotherapy.

Persons living with human immunodeficiency virus (PLWH) are at increased risk for cancers, including glioblastoma. Despite extensive research, both human immunodeficiency virus (HIV) and glioblastoma are incurable. The optimal treatment for concurrent HIV and glioblastoma is unknown. Early evidence suggests that immunotherapy can deplete residual HIV and restore immune function. We present a case of glioblastoma in a PLWH treated with immunotherapy. Treatment was well tolerated and safe. To our knowledge, this is the first reported case of a PLWH and glioblastoma treated with immunotherapy.

Epigenetic reprogramming shapes the cellular landscape of schwannoma.

Mechanisms specifying cancer cell states and response to therapy are incompletely understood. Here we show epigenetic reprogramming shapes the cellular landscape of schwannomas, the most common tumors of the peripheral nervous system. We find schwannomas are comprised of 2 molecular groups that are distinguished by activation of neural crest or nerve injury pathways that specify tumor cell states and the architecture of the tumor immune microenvironment. Moreover, we find radiotherapy is sufficient for interconversion of neural crest schwannomas to immune-enriched schwannomas through epigenetic and metabolic reprogramming. To define mechanisms underlying schwannoma groups, we develop a technique for simultaneous interrogation of chromatin accessibility and gene expression coupled with genetic and therapeutic perturbations in single-nuclei. Our results elucidate a framework for understanding epigenetic drivers of tumor evolution and establish a paradigm of epigenetic and metabolic reprograming of cancer cells that shapes the immune microenvironment in response to radiotherapy.

Functional interactions between neurofibromatosis tumor suppressors underlie Schwann cell tumor de-differentiation and treatment resistance.

Schwann cell tumors are the most common cancers of the peripheral nervous system and can arise in patients with neurofibromatosis type-1 (NF-1) or neurofibromatosis type-2 (NF-2). Functional interactions between NF1 and NF2 and broader mechanisms underlying malignant transformation of the Schwann lineage are unclear. Here we integrate bulk and single-cell genomics, biochemistry, and pharmacology across human samples, cell lines, and mouse allografts to identify cellular de-differentiation mechanisms driving malignant transformation and treatment resistance. We find DNA methylation groups of Schwann cell tumors can be distinguished by differentiation programs that correlate with response to the MEK inhibitor selumetinib. Functional genomic screening in NF1-mutant tumor cells reveals NF2 loss and PAK activation underlie selumetinib resistance, and we find that concurrent MEK and PAK inhibition is effective in vivo. These data support a de-differentiation paradigm underlying malignant transformation and treatment resistance of Schwann cell tumors and elucidate a functional link between NF1 and NF2.

Stromal Keratitis Associated With CMV Anterior Uveitis.

PURPOSE: Human cytomegalovirus (CMV) has commonly been reported as a cause of anterior uveitis and corneal endotheliitis. Unlike its other herpetic family members, herpes simplex virus and varicella zoster virus, involvement of the corneal stroma in CMV is uncommon. In this case series, we describe patients with CMV stromal keratitis. METHODS: This was a retrospective chart review of patients seen at a tertiary referral center from 1999 to 2023 with stromal keratitis who tested positive for CMV by directed polymerase chain reaction of aqueous fluid or corneal tissue. RESULTS: This series describes 5 patients, 4 of whom presented with anterior uveitis and stromal keratitis and were confirmed to be positive for CMV through the polymerase chain reaction of aqueous fluid. The fifth patient experienced recurrent corneal graft failures, with the most recent failed graft being positive for CMV based on immunohistochemical stains of the corneal stroma. The average age of patients was 62 years (range 36-80 years). Only 1 patient (20%) exhibited elevated intraocular pressure with stellate keratic precipitates at the initial presentation, whereas 3 other patients (60%) had a known history of glaucoma. CONCLUSIONS: Uveitis specialists are well aware of CMV as a cause of recurrent, hypertensive anterior uveitis but should also consider CMV in cases featuring stromal keratitis. The corneal endothelium may serve as a reservoir for both anterior uveitis and development of corneal stromal inflammation as demonstrated by the immunohistopathology exhibited in 1 case.

"De novo replication repair deficient glioblastoma, IDH-wildtype" is a distinct glioblastoma subtype in adults that may benefit from immune checkpoint blockade.

Glioblastoma is a clinically and molecularly heterogeneous disease, and new predictive biomarkers are needed to identify those patients most likely to respond to specific treatments. Through prospective genomic profiling of 459 consecutive primary treatment-naïve IDH-wildtype glioblastomas in adults, we identified a unique subgroup (2%, 9/459) defined by somatic hypermutation and DNA replication repair deficiency due to biallelic inactivation of a canonical mismatch repair gene. The deleterious mutations in mismatch repair genes were often present in the germline in the heterozygous state with somatic inactivation of the remaining allele, consistent with glioblastomas arising due to underlying Lynch syndrome. A subset of tumors had accompanying proofreading domain mutations in the DNA polymerase POLE and resultant "ultrahypermutation". The median age at diagnosis was 50 years (range 27-78), compared with 63 years for the other 450 patients with conventional glioblastoma (p < 0.01). All tumors had histologic features of the giant cell variant of glioblastoma. They lacked EGFR amplification, lacked combined trisomy of chromosome 7 plus monosomy of chromosome 10, and only rarely had TERT promoter mutation or CDKN2A homozygous deletion, which are hallmarks of conventional IDH-wildtype glioblastoma. Instead, they harbored frequent inactivating mutations in TP53, NF1, PTEN, ATRX, and SETD2 and recurrent activating mutations in PDGFRA. DNA methylation profiling revealed they did not align with known reference adult glioblastoma methylation classes, but instead had unique globally hypomethylated epigenomes and mostly classified as "Diffuse pediatric-type high grade glioma, RTK1 subtype, subclass A". Five patients were treated with immune checkpoint blockade, four of whom survived greater than 3 years. The median overall survival was 36.8 months, compared to 15.5 months for the other 450 patients (p < 0.001). We conclude that "De novo replication repair deficient glioblastoma, IDH-wildtype" represents a biologically distinct subtype in the adult population that may benefit from prospective identification and treatment with immune checkpoint blockade.

Pathological perspectives in pilocytic astrocytomas: Extent of resection as the sole critical factor for recurrence-free survival, and the challenge of evaluating conclusions derived from limited data.

Introduction: Pilocytic astrocytoma (PA) is one of the most common primary intracranial neoplasms in childhood with an overall favorable prognosis. Despite decades of experience, there are still diagnostic and treatment challenges and unresolved issues regarding risk factors associated with recurrence, most often due to conclusions of publications with limited data. We analyzed 499 patients with PA diagnosed in a single institution over 30 years in order to provide answers to some of the unresolved issues. Materials and Methods: We identified pilocytic astrocytomas diagnosed at the University of California, San Francisco, between 1989 and 2019, confirmed the diagnoses using the WHO 2021 essential and desirable criteria, and performed a retrospective review of the demographic and clinical features of the patients and the radiological, pathologic and molecular features of the tumors. Results: Among the patients identified from pathology archives, 499 cases fulfilled the inclusion criteria. Median age at presentation was 12 years (range 3.5 months - 73 years) and the median follow-up was 78.5 months. Tumors were predominantly located in the posterior fossa (52.6%). There were six deaths, but there were confounding factors that prevented a clear association of death to tumor progression. Extent of resection was the only significant factor for recurrence-free survival. Recurrence-free survival time was 321.0 months for gross total resection, compared to 160.9 months for subtotal resection (log rank, p <0.001). Conclusion: Multivariate analysis was able to identify extent of resection as the only significant variable to influence recurrence-free survival. We did not find a statistically significant association between age, NF1 status, tumor location, molecular alterations, and outcome. Smaller series with apparently significant results may have suffered from limited sample size, limited variables, acceptance of univariate analysis findings as well as a larger p value for biological significance. PA still remains a predominantly surgical disease and every attempt should be made to achieve gross total resection since this appears to be the most reliable predictor of recurrence-free survival.

Poorly differentiated orbital neuroendocrine carcinoma.

A man in his 70s presented with painless bilateral eyelid oedema and vertical diplopia. Evaluation showed a restrictive pattern of extraocular motility testing with MRI demonstrating significant enlargement of the right superior rectus and left superior oblique muscles along with right orbital fat stranding. Subsequent right orbital biopsy revealed poorly differentiated high-grade neuroendocrine carcinoma without a systemic primary site on further diagnostic workup. The patient was treated with carboplatin and etoposide and passed away from an infection a month after diagnosis. This case along with a review of other published cases highlights the varied presentation of orbital neuroendocrine carcinomas that may mimic a broad differential of orbital processes, thus requiring careful diagnostic workup. Subsequently, additional considerations in metastatic evaluation should be based on tumour histological features.

Novel SOX10 indel mutations drive schwannomas through impaired transactivation of myelination gene programs.

BACKGROUND: Schwannomas are common peripheral nerve sheath tumors that can cause severe morbidity given their stereotypic intracranial and paraspinal locations. Similar to many solid tumors, schwannomas and other nerve sheath tumors are primarily thought to arise due to aberrant hyperactivation of the RAS growth factor signaling pathway. Here, we sought to further define the molecular pathogenesis of schwannomas. METHODS: We performed comprehensive genomic profiling on a cohort of 96 human schwannomas, as well as DNA methylation profiling on a subset. Functional studies including RNA sequencing, chromatin immunoprecipitation-DNA sequencing, electrophoretic mobility shift assay, and luciferase reporter assays were performed in a fetal glial cell model following transduction with wildtype and tumor-derived mutant isoforms of SOX10. RESULTS: We identified that nearly one-third of sporadic schwannomas lack alterations in known nerve sheath tumor genes and instead harbor novel recurrent in-frame insertion/deletion mutations in SOX10, which encodes a transcription factor responsible for controlling Schwann cell differentiation and myelination. SOX10 indel mutations were highly enriched in schwannomas arising from nonvestibular cranial nerves (eg facial, trigeminal, vagus) and were absent from vestibular nerve schwannomas driven by NF2 mutation. Functional studies revealed these SOX10 indel mutations have retained DNA binding capacity but impaired transactivation of glial differentiation and myelination gene programs. CONCLUSIONS: We thus speculate that SOX10 indel mutations drive a unique subtype of schwannomas by impeding proper differentiation of immature Schwann cells.

Next-generation sequencing of a large uveal melanoma with whole genome doubling and a PBRM1 mutation.

Purpose: To report a large uveal melanoma with extra-scleral extension which underwent spontaneous infarction and its unique molecular signature profile. Observations: An 81-year-old female presented with a blind, painful eye. Intraocular pressure was 48 mm Hg. There was a large subconjunctival melanotic mass overlying a choroidal melanoma with anterior extension involving the ciliary body and the iridocorneal angle and iris. Ultrasonography confirmed a dome-shaped anterior cilio-choroidal mass with extra-scleral extension. The patient underwent enucleation and pathologic evaluation confirmed cilio-choroidal melanoma. The posterior half of the tumor involving the ciliary body and the extra-scleral component were spontaneously infarcted and were composed of large melanophages. Next-generation sequencing demonstrated a splice site mutation in PBRM1 and whole-genome doubling in addition to a GNAQ hotspot mutation, chromosome 3 loss and 8q gain. Conclusions and importance: This case of a large, auto-infarcted uveal melanoma demonstrates a PBRM1 mutation and whole-genome doubling.

A Case of Orbital Sarcoidosis with Caseating Granulomatous Inflammation.

The authors report a rare case of orbital sarcoidosis with caseating granulomatous inflammation. A 55-year-old man presented with a 2-month history of progressively worsening diplopia and proptosis of the OS. Orbital CT demonstrated a diffuse orbital mass. Diagnostic anterior orbitotomy demonstrated caseating granulomas. Infectious testing, including special stains, cultures, and polymerase chain reaction testing, were negative for infectious causes. Chest CT demonstrated the presence of hilar lymphadenopathy with bronchoscopic biopsy showing noncaseating granulomas, supporting a diagnosis of sarcoidosis. The patient achieved clinical and symptomatic improvement at 8-month follow-up on methotrexate. While sarcoidosis is typically characterized by non-necrotizing granulomatous inflammation, sarcoid granulomas with necrosis have been previously described in pulmonary histopathology. This case emphasizes the importance of a comprehensive systemic workup, keeping systemic sarcoidosis on the differential, for necrotizing granulomatous inflammation of the orbit.

Prognostic Value of BAP1 and Preferentially Expressed Antigen in Melanoma (PRAME) Immunohistochemistry in Uveal Melanomas.

Uveal melanoma (UM) is the most common primary intraocular tumor in adults, and despite excellent local control, more than 50% of patients develop and die from metastatic disease. Loss of BAP1 nuclear staining, a surrogate marker of BAP1 mutation, and preferentially expressed antigen in melanoma (PRAME) messenger RNA overexpression, as assessed using qPCR, have previously been shown to correlate with increased metastasis rate in UM. In this study, we demonstrated that UM could be successfully risk-stratified using a combination of BAP1 and PRAME immunohistochemical (IHC) stains. We retrospectively reviewed 318 UM cases with sufficient tissue and performed BAP1 and PRAME IHC to stratify them as BAP1+/PRAME- (group 1, n = 135), BAP1+/PRAME+ (group 2, n = 43), BAP1-/PRAME- (group 3, n = 94), and BAP1-/PRAME+ (group 4, n = 46). Increasing the study risk group on the basis of loss of BAP1 expression and positive PRAME staining was associated with a higher rate of metastasis and disease-specific death and lower metastasis-free survival (MFS) and disease-specific survival (DSS). Among tumors with loss of BAP1 staining, PRAME positivity was associated with shorter MFS (P = .018) and showed a trend toward shorter DSS (P = .061). Among tumors with retained BAP1 staining, PRAME positivity was associated with shorter MFS and DSS (P = .001 and P = .021, respectively). In summary, a combination of BAP1 and PRAME IHC can be used for risk stratification of UMs.

Rapid pre-retinal ossification presenting as a vascularized lesion over an area of chronic retinal detachment.

Purpose: To describe the clinical, optical coherence tomography (OCT), and histopathological findings of a patient who was found to have ossification of a pre-retinal membrane after multiple surgical repairs for retinal detachment. Methods: The patient had comprehensive ophthalmic examinations during seven years of follow-up and underwent surgical removal of her pre-retinal membrane. Results: A 24-year-old woman with a history of retinal detachment and multiple retina surgeries presented with baseline vision of 20/200 and refractory glaucoma in the left eye (right eye with no light perception due to prior failed retinal detachment repair). OCT showed a thick epiretinal membrane with hypo-reflective intraretinal spaces in the macula, and exam revealed a chronic retinal detachment superotemporally surrounded by laser barricade. She was stable for six years and then experienced vision loss and decreasing eye pressure, concurrent with rapid evolution of pre-retinal fibrosis, leading to a vascularized consolidation in the mid-periphery, for which she underwent vitrectomy and membrane peel. The vascularized lesion over the area of detachment in the superotemporal retina was removed en bloc through the anterior chamber. Pathological findings revealed woven bone formation anterior to the internal limiting membrane, and the tissue was GFAP negative. Conclusions: Our case adds to the limited knowledge of the chronology, presentation, and surgical management of intraocular ossification, especially of the rarer pre-retinal type. Our patient highlights that development of ossification can happen more quickly than previously thought (year or years rather than decades), can be hidden under vascularized lesions, and is dynamic, with simultaneous release of traction in one area and increased traction in another. Diligent follow-up is indicated even in cases of vitreous membranes from retinal detachment that otherwise appear to have been stable for years.

Uterine Inflammatory Myofibroblastic Tumors: Proposed Risk Stratification Model Using Integrated Clinicopathologic and Molecular Analysis.

Inflammatory myofibroblastic tumor (IMT) of the uterus is a rare mesenchymal tumor with largely benign behavior; however, a small subset demonstrate aggressive behavior. While clinicopathologic features have been previously associated with aggressive behavior, these reports are based on small series, and these features are imperfect predictors of clinical behavior. IMTs are most commonly driven by ALK fusions, with additional pathogenic molecular alterations being reported only in rare examples of extrauterine IMTs. In this study, a series of 11 uterine IMTs, 5 of which demonstrated aggressive behavior, were evaluated for clinicopathologic variables and additionally subjected to capture-based next-generation sequencing with or without whole-transcriptome RNA sequencing. In the 6 IMTs without aggressive behavior, ALK fusions were the sole pathogenic alteration. In contrast, all 5 aggressive IMTs harbored pathogenic molecular alterations and numerous copy number changes in addition to ALK fusions, with the majority of the additional alterations present in the primary tumors. We combined our series with cases previously reported in the literature and performed statistical analyses to propose a novel clinicopathologic risk stratification score assigning 1 point each for: age above 45 years, size≥5 cm,≥4 mitotic figures per 10 high-power field, and infiltrative borders. No tumors with 0 points had an aggressive outcome, while 21% of tumors with 1 to 2 points and all tumors with ≥3 points had aggressive outcomes. We propose a 2-step classification model that first uses the clinicopathologic risk stratification score to identify low-risk and high-risk tumors, and recommend molecular testing to further classify intermediate-risk tumors.

Towards Development of a Standard Terminology of the World Health Organization Classification of Tumors of the Central Nervous System in the Turkish Language, and a Perspective on the Practical Implications of the WHO Classification for Low and Middle Income Countries.

In our manuscript, we propose a common terminology in the Turkish language for the newly adopted WHO classification of the CNS tumors, also known as the WHO CNS 5th edition. We also comment on the applicability of this new scheme in low and middle income countries, and warn about further deepening disparities between the global north and the global south. This division, augmented by the recent COVID-19 pandemic, threatens our ability to coordinate efforts worldwide and may create significant disparities in the diagnosis and treatment of cancers between the "haves" and the "have nots".

Multiplatform molecular analyses refine classification of gliomas arising in patients with neurofibromatosis type 1.

Gliomas arising in the setting of neurofibromatosis type 1 (NF1) are heterogeneous, occurring from childhood through adulthood, can be histologically low-grade or high-grade, and follow an indolent or aggressive clinical course. Comprehensive profiling of genetic alterations beyond NF1 inactivation and epigenetic classification of these tumors remain limited. Through next-generation sequencing, copy number analysis, and DNA methylation profiling of gliomas from 47 NF1 patients, we identified 2 molecular subgroups of NF1-associated gliomas. The first harbored biallelic NF1 inactivation only, occurred primarily during childhood, followed a more indolent clinical course, and had a unique epigenetic signature for which we propose the terminology "pilocytic astrocytoma, arising in the setting of NF1". The second subgroup harbored additional oncogenic alterations including CDKN2A homozygous deletion and ATRX mutation, occurred primarily during adulthood, followed a more aggressive clinical course, and was epigenetically diverse, with most tumors aligning with either high-grade astrocytoma with piloid features or various subclasses of IDH-wildtype glioblastoma. Several patients were treated with small molecule MEK inhibitors that resulted in stable disease or tumor regression when used as a single agent, but only in the context of those tumors with NF1 inactivation lacking additional oncogenic alterations. Together, these findings highlight recurrently altered pathways in NF1-associated gliomas and help inform targeted therapeutic strategies for this patient population.