The landscape of submicroscopic structural variants at the OPN1LW/OPN1MW gene cluster on Xq28 underlying blue cone monochromacy.

Blue cone monochromacy (BCM) is an X-linked retinal disorder characterized by low vision, photoaversion, and poor color discrimination. BCM is due to the lack of long-wavelength-sensitive and middle-wavelength-sensitive cone photoreceptor function and caused by mutations in the OPN1LW/OPN1MW gene cluster on Xq28. Here, we investigated the prevalence and the landscape of submicroscopic structural variants (SVs) at single-base resolution in BCM patients. We found that about one-third (n = 73) of the 213 molecularly confirmed BCM families carry an SV, most commonly deletions restricted to the OPN1LW/OPN1MW gene cluster. The structure and precise breakpoints of the SVs were resolved in all but one of the 73 families. Twenty-two families-all from the United States-showed the same SV, and we confirmed a common ancestry of this mutation. In total, 42 distinct SVs were identified, including 40 previously unreported SVs, thereby quadrupling the number of precisely mapped SVs underlying BCM. Notably, there was no "region of overlap" among these SVs. However, 90% of SVs encompass the upstream locus control region, an essential enhancer element. Its minimal functional extent based on deletion mapping in patients was refined to 358 bp. Breakpoint analyses suggest diverse mechanisms underlying SV formation as well as in one case the gene conversion-based exchange of a 142-bp deletion between opsin genes. Using parsimonious assumptions, we reconstructed the composition and copy number of the OPN1LW/OPN1MW gene cluster prior to the mutation event and found evidence that large gene arrays may be predisposed to the occurrence of SVs at this locus.

GM-CSF, G-CSF or no cytokine therapy with anti-GD2 immunotherapy for high-risk neuroblastoma.

Colony-stimulating factors have been shown to improve anti-disialoganglioside 2 (anti-GD2) monoclonal antibody response in high-risk neuroblastoma by enhancing antibody-dependent cell-mediated cytotoxicity (ADCC). A substantial amount of research has focused on recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) as an adjuvant to anti-GD2 monoclonal antibodies. There may be a disparity in care among patients as access to GM-CSF therapy and anti-GD2 monoclonal antibodies is not uniform. Only select countries have approved these agents for use, and even with regulatory approvals, access to these agents can be complex and cost prohibitive. This comprehensive review summarizes clinical data regarding efficacy and safety of GM-CSF, recombinant human granulocyte colony-stimulating factor (G-CSF) or no cytokine in combination with anti-GD2 monoclonal antibodies (ie, dinutuximab, dinutuximab beta or naxitamab) for immunotherapy of patients with high-risk neuroblastoma. A substantial body of clinical data support the immunotherapy combination of anti-GD2 monoclonal antibodies and GM-CSF. In contrast, clinical data supporting the use of G-CSF are limited. No formal comparison between GM-CSF, G-CSF and no cytokine has been identified. The treatment of high-risk neuroblastoma with anti-GD2 therapy plus GM-CSF is well established. Suboptimal efficacy outcomes with G-CSF raise concerns about its suitability as an alternative to GM-CSF as an adjuvant in immunotherapy for patients with high-risk neuroblastoma. While programs exist to facilitate obtaining GM-CSF and anti-GD2 monoclonal antibodies in regions where they are not commercially available, continued work is needed to ensure equitable therapeutic options are available globally.

Radiation recall reaction induced by gemcitabine/docetaxel in children: A retrospective study on risk factors and outcomes.

INTRODUCTION: Radiation recall reaction (RRR) is a rare inflammatory reaction developing in a previously irradiated field after a triggering agent. In pediatric patients, it is poorly understood and deficiently studied. Gemcitabine-docetaxel (G/D) in childhood cancer is mainly used as a salvage regimen for sarcomas. We aim to describe RRR triggered by G/D in children. PATIENTS AND METHODS: Retrospective review of 21 patients receiving G/D along with radiotherapy at two hospitals from 2010 until 2022. RRR was considered as any toxicity occurring after G/D administration in a previously irradiated field. RRR features were described. Fisher's and Mann-Whitney tests were utilized to analyze the risk factors involved. RESULTS: Sixteen episodes of RRR developed in 16 (76.2%) patients. RRR mainly involved deep layers of the skin (58%) and occurred predominantly after two G/D cycles. The mean time between radiotherapy and chemotherapy was 28.5 days (0-1359 days), and the mean radiation volume 391 mL (157-1810 mL) for RRR. RRR treatment was mainly systemic steroids, with partial responses in six of 11 (58%) patients. Re-exposure to G/D was associated with a high rate of recurrence in nine of 15 (56.2%), prompting drug discontinuation. The major risk factors for RRR after G/D include, without statistical significance, a larger volume of the irradiated field and a shorter interval between chemotherapy and radiotherapy. CONCLUSIONS: The incidence of RRR after G/D in the pediatric population is higher than previously reported. Drug re-exposure is usually followed by recurrence. Higher irradiated volumes and a shorter time to the start of chemotherapy could be related with an increased risk of RRR.

Optical coherence tomography biomarkers in MYO7A-inherited retinal dystrophy: longitudinal study in pediatric patients.

PURPOSE: This study aims to answer a key question: is MYO7A-inherited retinal dystrophy (MYO7A-IRD) a photoreceptor-first or retinal pigment epithelium-first disease? A second aim was to determine the most useful biomarkers to monitor disease progression in pediatric patients with Usher syndrome type 1B (USH1) secondary to MYO7A mutation. METHODS: Fifty-two eyes from 26 patients with genetically-confirmed MYO7A-IRD underwent swept-source optical coherence tomography (SS-OCT). Structural abnormalities were evaluated and correlated with follow-up time and best corrected visual acuity (BCVA). All patients were evaluated at baseline and after ≥ 40 months of follow-up. RESULTS: The mean (SD) patient age was 9.92 (± 4.1) years. Mean follow-up time was 43 (± 3.2) months. At the final evaluation, the most common qualitative abnormalities in the subfoveal area were alterations in the photoreceptor outer segments (76.9% of eyes) and in the interdigitation zone (IZ) (80.8%). The presence of cystoid macular edema at baseline was independently associated with worse BCVA at the final assessment (increase in LogMAR estimate = 0.142; t(45.00) = 2.78, p = 0.009). The mean width of the ellipsoid and interdigitation zones decreased significantly (by 668 µm and 278 µm, respectively; both p < 0.001). CONCLUSION: This study shows that disruption of the photoreceptor outer segments and the IZ are the first alterations detected by SS-OCT in the early phases of MYO7A-IRD. These data highlight the potential value of measuring the width of the ellipsoid and IZ to evaluate disease progression. These findings also demonstrate the utility of monitoring for the emergence of cystic lesions as biomarkers of worse visual prognosis in patients with MYO7A-IRD.

Prognostic value of xenograft engraftment in patients with metastatic high-risk neuroblastoma.

BACKGROUND: Successful engraftment of human cancer biopsies in immunodeficient mice correlates with the poor prognosis of patients. This was reported 30 years ago for children with neuroblastoma, but the standard of care treatment evolved significantly during the last 15 years, leading to improved survival of these patients. Here, we evaluated the association of patient-derived xenograft (PDX) engraftment and prognosis in patients receiving up-to-date treatments for cancers classified as metastatic (stage M) high-risk neuroblastoma (HR-NB) by the International Neuroblastoma Risk Group Staging System (INRGSS). METHODS: We obtained biopsies from patients with stage M HR-NB. We inoculated biopsy fragments subcutaneously in mice. We studied the association of PDX engraftment with event-free survival (EFS) and overall survival (OS) of patients. RESULTS: Since 2009, we established 17 PDX from 97 samples of 66 patients with stage M HR-NB, with a follow-up of at least two years. Factors associated with higher probability of engraftment were the death as outcome (p = .0006) and the amplification of the gene MYCN in tumors (p = .0271). Patients whose biopsies established a PDX had significantly shorter EFS and OS (p = .0039 and .0002, respectively) than patients whose samples did not engraft. The association of PDX engraftment and OS was significant in patients without MYCN amplification (p = .0041), but not in patients with MYCN amplification (p = .2707). CONCLUSION: Positive PDX engraftment is a factor related to poor prognosis and fatal outcome in patients with stage M HR-NB treated with up-to-date therapies.

Identification of immunosuppressive factors in retinoblastoma cell secretomes and aqueous humor from patients.

The microenvironment of retinoblastoma, the solid malignancy of the developing retina, is immunosuppressive. To study the interactions between tumor-associated microglia/macrophages (TAMs) and tumor cells in retinoblastomas, we analyzed immunohistochemistry markers in 23 patient samples and characterized 105 secreted cytokines of 11 retinoblastoma cell models in culture. We detected profuse infiltration of CD163+ protumoral M2-like polarized TAMs in eyes enucleated due to cancer progression. Previous treatment of patients increased the number of TAMs but did not affect M2-like polarization. M2-like microglia/macrophages were almost absent in five eyes obtained from children enucleated due to nontumoral causes. CD8+ tumor-infiltrating lymphocytes (TILs) were moderately abundant in tumor eyes and very scarce in nontumoral ones. The expression of the immune checkpoint molecule PD-L1 was absent in 95% of the tumor samples, which is concordant with the finding of FOXP3+ Tregs infiltrating tumors. We confirmed the pathology results using single-cell transcriptome analysis of one tumor. We identified the cytokines extracellular matrix metalloproteinase inducer (EMMPRIN) and macrophage migration inhibitory factor (MIF), both with reported immunosuppressive activity, secreted at high levels in retinoblastoma primary cell cultures. Gene expression analysis of a large retinoblastoma cohort and single-cell transcriptome analysis confirmed that MIF and EMMPRIN were significantly upregulated in retinoblastomas, which led us to quantify both proteins by immunoassays in liquid biopsies (aqueous humor obtained from more than 20 retinoblastoma patients). We found a significant increase in the concentration of MIF and EMMPRIN in cancer patients, compared to 12 noncancer ones. Finally, we showed that macrophages derived from peripheral blood mononuclear cells increased the expression of markers of M2-like polarization upon exposure to retinoblastoma-conditioned medium or recombinant MIF. Overall, our findings suggest that retinoblastoma cell secretions induce the protumoral phenotype of this tumor. Our results might have clinical impact in the fields of biomarkers and treatment. © 2022 The Pathological Society of Great Britain and Ireland.

Vitamin D Status in Children With High-risk Neuroblastoma.

BACKGROUND: Vitamin D deficiency has become a matter of concern in pediatric cancer patients. A relationship between neuroblastoma and Vitamin D signaling pathways has been revealed with interest in the antiproliferative and antiinvasive properties of vitamin D. Our aim is to describe the prevalence of Vitamin D deficiency among children with high-risk neuroblastoma (HR-NB) and to explore its association with disease status. MATERIALS AND METHODS: In all, 182 patients with HR-NB were managed at our center from 2017 to 2021. Serum 25(OH)D levels were tested at the first blood analysis performed and correlated with clinical data and disease status. RESULTS: One hundred forty-eight (81.4%) had low 25(OH)D levels (48.4% categorized as deficiency (25(OH)D below 20 ng/mL) and 33.0% as insufficiency (25(OH)D 20 to 30 ng/mL). Median Vitamin D level was 20.2 ng/mL. Vitamin D levels were not associated with race or sex. Although malnourished patients had lower median 25(OH)D levels(11.1 ng/mL), no statistical association was observed with Vitamin D deficiency. There was no association between Vitamin D levels and disease status. An inverse correlation was found between age and vitamin D levels ( P =0.0040). CONCLUSION: A concerning high prevalence of low Vitamin D levels affects more than two-thirds of patients with HR-NB in our cohort, regardless of the disease status at the time of evaluation. Older children are at a higher risk for deficient levels of vitamin D.

Comprehensive variant spectrum of the CNGA3 gene in patients affected by achromatopsia.

Achromatopsia (ACHM) is a congenital cone photoreceptor disorder characterized by impaired color discrimination, low visual acuity, photosensitivity, and nystagmus. To date, six genes have been associated with ACHM (CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6), the majority of these being implicated in the cone phototransduction cascade. CNGA3 encodes the CNGA3 subunit of the cyclic nucleotide-gated ion channel in cone photoreceptors and is one of the major disease-associated genes for ACHM. Herein, we provide a comprehensive overview of the CNGA3 variant spectrum in a cohort of 1060 genetically confirmed ACHM patients, 385 (36.3%) of these carrying "likely disease-causing" variants in CNGA3. Compiling our own genetic data with those reported in the literature and in public databases, we further extend the CNGA3 variant spectrum to a total of 316 variants, 244 of which we interpreted as "likely disease-causing" according to ACMG/AMP criteria. We report 48 novel "likely disease-causing" variants, 24 of which are missense substitutions underlining the predominant role of this mutation class in the CNGA3 variant spectrum. In addition, we provide extensive in silico analyses and summarize reported functional data of previously analyzed missense, nonsense and splicing variants to further advance the pathogenicity assessment of the identified variants.

High-risk Pathologic Features Based on Presenting Findings in Advanced Intraocular Retinoblastoma: A Multicenter, International Data-Sharing American Joint Committee on Cancer Study.

PURPOSE: To determine the value of clinical features for advanced intraocular retinoblastoma as defined by the eighth edition of the American Joint Committee on Cancer (AJCC) cT3 category and AJCC Ophthalmic Oncology Task Force (OOTF) Size Groups to predict the high-risk pathologic features. DESIGN: International, multicenter, registry-based retrospective case series. PARTICIPANTS: Eighteen ophthalmic oncology centers from 13 countries over 6 continents shared evaluations of 942 eyes enucleated as primary treatment for AJCC cT3 and, for comparison, cT2 retinoblastoma. METHODS: International, multicenter, registry-based data were pooled from patients enrolled between 2001 and 2013. High-risk pathologic features were defined as AJCC categories pT3 and pT4. In addition, AJCC OOTF Size Groups were defined as follows: (1) less than half, (2) more than half but less than two thirds, (3) more than two thirds of globe volume involved, and (4) diffuse infiltrating retinoblastoma. MAIN OUTCOME MEASURES: Statistical risk of high-risk pathologic features corresponding to AJCC cT3 subcategories and AJCC OOTF Size Groups. RESULTS: Of 942 retinoblastoma eyes treated by primary enucleation, 282 (30%) showed high-risk pathologic features. Both cT subcategories and AJCC OOTF Size Groups (P < 0.001 for both) were associated with high-risk pathologic features. On logistic regression analysis, cT3c (iris neovascularization with glaucoma), cT3d (intraocular hemorrhage), and cT3e (aseptic orbital cellulitis) were predictive factors for high-risk pathologic features when compared with cT2a with an odds ratio of 2.3 (P = 0.002), 2.5 (P = 0.002), and 3.3 (P = 0.019), respectively. Size Group 3 (more than two-thirds globe volume) and 4 (diffuse infiltrative retinoblastoma) were the best predictive factors with an odds ratio of 3.3 and 4.1 (P < 0.001 for both), respectively, for high-risk pathologic features when compared with Size Groups 1 (i.e., < 50% of globe volume). CONCLUSIONS: The AJCC retinoblastoma staging clinical cT3c-e subcategories (glaucoma, intraocular hemorrhage, and aseptic orbital cellulitis, respectively) as well as the AJCC OOTF Size Groups 3 (tumor more than two thirds of globe volume) and 4 (diffuse infiltrative retinoblastoma) both allowed stratification of clinical risk factors that can be used to predict the presence of high-risk pathologic features and thus facilitate treatment decisions.

Metastatic Death Based on Presenting Features and Treatment for Advanced Intraocular Retinoblastoma: A Multicenter Registry-Based Study.

PURPOSE: To evaluate presenting features, tumor size, and treatment methods for risk of metastatic death due to advanced intraocular retinoblastoma (RB). DESIGN: International, multicenter, registry-based retrospective case series. PARTICIPANTS: A total of 1841 patients with advanced RB. METHODS: Advanced RB was defined by 8th edition American Joint Committee on Cancer (AJCC) categories cT2 and cT3 and new AJCC-Ophthalmic Oncology Task Force (OOTF) Size Groups (1: < 50% of globe volume, 2: > 50% but < 2/3, 3: > 2/3, and 4: diffuse infiltrating RB). Treatments were primary enucleation, systemic chemotherapy with secondary enucleation, and systemic chemotherapy with eye salvage. MAIN OUTCOME MEASURES: Metastatic death. RESULTS: The 5-year Kaplan-Meier cumulative survival estimates by patient-level AJCC clinical subcategories were 98% for cT2a, 96% for cT2b, 88% for cT3a, 95% for cT3b, 92% for cT3c, 84% for cT3d, and 75% for cT3e RB. Survival estimates by treatment modality were 96% for primary enucleation, 89% for systemic chemotherapy and secondary enucleation, and 90% for systemic chemotherapy with eye salvage. Risk of metastatic mortality increased with increasing cT subcategory (P < 0.001). Cox proportional hazards regression analysis confirmed a higher risk of metastatic mortality in categories cT3c (glaucoma, hazard ratio [HR], 4.9; P = 0.011), cT3d (intraocular hemorrhage, HR, 14.0; P < 0.001), and cT3e (orbital cellulitis, HR, 19.6; P < 0.001) than in category cT2a and with systemic chemotherapy with secondary enucleation (HR, 3.3; P < 0.001) and eye salvage (HR, 4.9; P < 0.001) than with primary enucleation. The 5-year Kaplan-Meier cumulative survival estimates by AJCC-OOTF Size Groups 1 to 4 were 99%, 96%, 94%, and 83%, respectively. Mortality from metastatic RB increased with increasing Size Group (P < 0.001). Cox proportional hazards regression analysis revealed that patients with Size Group 3 (HR, 10.0; P = 0.002) and 4 (HR, 41.1; P < 0.001) had a greater risk of metastatic mortality than Size Group 1. CONCLUSIONS: The AJCC-RB cT2 and cT3 subcategories and size-based AJCC-OOTF Groups 3 (> 2/3 globe volume) and 4 (diffuse infiltrating RB) provided a robust stratification of clinical risk for metastatic death in advanced intraocular RB. Primary enucleation offered the highest survival rates for patients with advanced intraocular RB.

MIF/CXCR4 signaling axis contributes to survival, invasion, and drug resistance of metastatic neuroblastoma cells in the bone marrow microenvironment.

BACKGROUND: The bone marrow (BM) is the most common site of dissemination in patients with aggressive, metastatic neuroblastoma (NB). However, the molecular mechanisms underlying the aggressive behavior of NB cells in the BM niche are still greatly unknown. In the present study, we explored biological mechanisms that play a critical role in NB cell survival and progression in the BM and investigated potential therapeutic targets. METHODS: Patient-derived bone marrow (BM) primary cultures were generated using fresh BM aspirates obtained from NB patients. NB cell lines were cultured in the presence of BM conditioned media containing cell-secreted factors, and under low oxygen levels (1% O2) to mimic specific features of the BM microenvironment of high-risk NB patients. The BM niche was explored using cytokine profiling assays, cell migration-invasion and viability assays, flow cytometry and analysis of RNA-sequencing data. Selective pharmacological inhibition of factors identified as potential mediators of NB progression within the BM niche was performed in vitro and in vivo. RESULTS: We identified macrophage migration inhibitory factor (MIF) as a key inflammatory cytokine involved in BM infiltration. Cytokine profiling and RNA-sequencing data analysis revealed NB cells as the main source of MIF in the BM, suggesting a potential role of MIF in tumor invasion. Exposure of NB cells to BM-conditions increased NB cell-surface expression of the MIF receptor CXCR4, which was associated with increased cell viability, enhanced migration-invasion, and activation of PI3K/AKT and MAPK/ERK signaling pathways. Moreover, subcutaneous co-injection of NB and BM cells enhanced tumor engraftment in mice. MIF inhibition with 4-IPP impaired in vitro NB aggressiveness, and improved drug response while delayed NB growth, improving survival of the NB xenograft model. CONCLUSIONS: Our findings suggest that BM infiltration by NB cells may be mediated, in part, by MIF-CXCR4 signaling. We demonstrate the antitumor efficacy of MIF targeting in vitro and in vivo that could represent a novel therapeutic target for patients with disseminated high-risk NB.

New-onset non-lesional aphasic status epilepticus. Clinical description, diagnostic clues, and treatment algorithm.

OBJECTIVES: De novo aphasic status epilepticus (ASE) in patients without a previous history of epilepsy and without cerebral lesions (aphasic NOSE) is rare. The aim of the study is to describe its clinical characteristics, etiologies, and outcome. MATERIALS & METHODS: Single-center study including consecutive patients presenting to the emergency department between 2011 and 2019 with acute aphasia, which was finally diagnosed as aphasic NOSE. Subsequent episodes of aphasia (>5 min) were recorded and divided into confirmed ASE and postictal aphasic episodes (non-ASE). Clinical characteristics of the two types of episodes were compared. RESULTS: Nineteen patients were included, suffering fifty episodes of epileptic aphasia, episodes per patient 2.6 (range 1-7). Fifteen patients (71.4%) were women, mean age at ASE onset was 66.05 years old (SD 6.3). Nine (47%) patients died, 6 of them (66.7%) during the aphasic episode. Ictal EEG was available in 37 episodes, confirming the diagnosis of ASE in 12 episodes; in 8 episodes, the EEG fulfilled the criteria of possible ASE. The most frequent etiologies were inflammatory and vascular. Comparing ASE with non-ASE episodes, ASE was longer than non-ASE (225 vs 65 h, p .024) and was treated more frequently with BZD (76 vs 24%, p .001) but with a longer delay (22.2 vs 1.5 h, p .06). CONCLUSIONS: ASE is a treatable, highly relapsing emergency, with the subsequent relapses ASE or postictal aphasia. EEG is diagnostic in half of the patients, while in others imaging techniques are also useful. Benzodiazepines should be administered. Persistent aphasia, of more than 65 hours' duration, is highly suggestive of ASE.

AC-265347 Inhibits Neuroblastoma Tumor Growth by Induction of Differentiation without Causing Hypocalcemia.

Neuroblastoma is the most common extracranial solid tumor of childhood, with heterogeneous clinical manifestations ranging from spontaneous regression to aggressive metastatic disease. The calcium-sensing receptor (CaSR) is a G protein-coupled receptor (GPCR) that senses plasmatic fluctuation in the extracellular concentration of calcium and plays a key role in maintaining calcium homeostasis. We have previously reported that this receptor exhibits tumor suppressor properties in neuroblastoma. The activation of CaSR with cinacalcet, a positive allosteric modulator of CaSR, reduces neuroblastoma tumor growth by promoting differentiation, endoplasmic reticulum (ER) stress and apoptosis. However, cinacalcet treatment results in unmanageable hypocalcemia in patients. Based on the bias signaling shown by calcimimetics, we aimed to identify a new drug that might exert tumor-growth inhibition similar to cinacalcet, without affecting plasma calcium levels. We identified a structurally different calcimimetic, AC-265347, as a promising therapeutic agent for neuroblastoma, since it reduced tumor growth by induction of differentiation, without affecting plasma calcium levels. Microarray analysis suggested biased allosteric modulation of the CaSR signaling by AC-265347 and cinacalcet towards distinct intracellular pathways. No upregulation of genes involved in calcium signaling and ER stress were observed in patient-derived xenografts (PDX) models exposed to AC-265347. Moreover, the most significant upregulated biological pathways promoted by AC-265347 were linked to RHO GTPases signaling. AC-265347 upregulated cancer testis antigens (CTAs), providing new opportunities for CTA-based immunotherapies. Taken together, this study highlights the importance of the biased allosteric modulation when targeting GPCRs in cancer. More importantly, the capacity of AC-265347 to promote differentiation of malignant neuroblastoma cells provides new opportunities, alone or in combination with other drugs, to treat high-risk neuroblastoma patients.

Clinicopathologic and molecular analysis of embryonal rhabdomyosarcoma of the genitourinary tract: evidence for a distinct DICER1-associated subgroup.

Embryonal rhabdomyosarcoma (ERMS) of the uterus has recently been shown to frequently harbor DICER1 mutations. Interestingly, only rare cases of extrauterine DICER1-associated ERMS, mostly located in the genitourinary tract, have been reported to date. Our goal was to study clinicopathologic and molecular profiles of DICER1-mutant (DICER1-mut) and DICER1-wild type (DICER1-wt) ERMS in a cohort of genitourinary tumors. We collected a cohort of 17 ERMS including nine uterine (four uterine corpus and five cervix), one vaginal, and seven urinary tract tumors. DNA sequencing revealed mutations of DICER1 in 9/9 uterine ERMS. All other ERMS of our cohort were DICER1-wt. The median age at diagnosis of patients with DICER1-mut and DICER1-wt ERMS was 36 years and 5 years, respectively. Limited follow-up data (available for 15/17 patients) suggested that DICER1-mut ERMS might show a less aggressive clinical course than DICER1-wt ERMS. Histological features only observed in DICER1-mut ERMS were cartilaginous nodules (6/9 DICER1-mut ERMS), in one case accompanied by foci of ossification. Recurrent mutations identified in both DICER1-mut and DICER1-wt ERMS affected KRAS, NRAS, and TP53. Copy number analysis revealed similar structural variations with frequent gains on chromosomes 2, 3, and 8, independent of DICER1 mutation status. Unsupervised hierarchical clustering of array-based whole-genome DNA methylation data of our study cohort together with an extended methylation data set including different RMS subtypes from genitourinary and extra-genitourinary locations (n = 102), revealed a distinct cluster for DICER1-mut ERMS. Such tumors clearly segregated from the clusters of DICER1-wt ERMS, alveolar RMS, and MYOD1-mutant spindle cell and sclerosing RMS. Only one tumor, previously diagnosed as ERMS arising in the maxilla of a 6-year-old boy clustered with DICER1-mut ERMS of the uterus. Subsequent sequencing analysis identified two DICER1 mutations in the latter case. Our results suggest that DICER1-mut ERMS might qualify as a distinct subtype in future classifications of RMS.

Subgroup and subtype-specific outcomes in adult medulloblastoma.

Medulloblastoma, a common pediatric malignant central nervous system tumour, represent a small proportion of brain tumours in adults. Previously it has been shown that in adults, Sonic Hedgehog (SHH)-activated tumours predominate, with Wingless-type (WNT) and Group 4 being less common, but molecular risk stratification remains a challenge. We performed an integrated analysis consisting of genome-wide methylation profiling, copy number profiling, somatic nucleotide variants and correlation of clinical variables across a cohort of 191 adult medulloblastoma cases identified through the Medulloblastoma Advanced Genomics International Consortium. We identified 30 WNT, 112 SHH, 6 Group 3, and 41 Group 4 tumours. Patients with SHH tumours were significantly older at diagnosis compared to other subgroups (p < 0.0001). Five-year progression-free survival (PFS) for WNT, SHH, Group 3, and Group 4 tumours was 64.4 (48.0-86.5), 61.9% (51.6-74.2), 80.0% (95% CI 51.6-100.0), and 44.9% (95% CI 28.6-70.7), respectively (p = 0.06). None of the clinical variables (age, sex, metastatic status, extent of resection, chemotherapy, radiotherapy) were associated with subgroup-specific PFS. Survival among patients with SHH tumours was significantly worse for cases with chromosome 3p loss (HR 2.9, 95% CI 1.1-7.6; p = 0.02), chromosome 10q loss (HR 4.6, 95% CI 2.3-9.4; p < 0.0001), chromosome 17p loss (HR 2.3, 95% CI 1.1-4.8; p = 0.02), and PTCH1 mutations (HR 2.6, 95% CI 1.1-6.2; p = 0.04). The prognostic significance of 3p loss and 10q loss persisted in multivariable regression models. For Group 4 tumours, chromosome 8 loss was strongly associated with improved survival, which was validated in a non-overlapping cohort (combined cohort HR 0.2, 95% CI 0.1-0.7; p = 0.007). Unlike in pediatric medulloblastoma, whole chromosome 11 loss in Group 4 and chromosome 14q loss in SHH was not associated with improved survival, where MYCN, GLI2 and MYC amplification were rare. In sum, we report unique subgroup-specific cytogenetic features of adult medulloblastoma, which are distinct from those in younger patients, and correlate with survival disparities. Our findings suggest that clinical trials that incorporate new strategies tailored to high-risk adult medulloblastoma patients are urgently needed.

Naxitamab combined with granulocyte-macrophage colony-stimulating factor as consolidation for high-risk neuroblastoma patients in complete remission.

BACKGROUND: Naxitamab is a humanized anti-disialoganglioside (GD2) monoclonal antibody approved for treatment of bone/bone marrow refractory high-risk neuroblastoma (HR-NB). Compassionate use (CU) expanded access program at Hospital Sant Joan de Deu permitted treatment of patients in complete remission (CR). We here report the survival, toxicity, and relapse pattern of patients in first or second CR treated with naxitamab and sargramostim (GM-CSF). PROCEDURE: Seventy-three consecutive patients with HR-NB (stage M at age >18 months or MYCN-amplified stages L1/L2 at any age) were treated in first or second CR. Treatment comprised five cycles of subcutaneous (SC) GM-CSF for 5 days at 250 µg/m2 /day (days -4 to 0), followed by naxitamab + SC GM-CSF for 5 days at 500 µg/m2 /day (days 1-5). Naxitamab was infused over 30 minutes at 3 mg/kg/day, days 1, 3, and 5, outpatient. RESULTS: Fifty-five patients were in first CR and 18 in second CR. Seventeen patients had MYCN-amplified NB and 11 detectable minimal residual disease in the bone marrow. Fifty-eight (79.5%) patients completed therapy. Four (5%) experienced grade 4 toxicities and 10 (14%) early relapse. Three-year event-free survival (EFS) 58.4%, 95% CI = (43.5%, 78.4%) and overall survival (OS) 82.4%, 95% CI = (66.8%, 100%). First CR patients 3-year EFS 74.3%, 95% CI = (62.7%, 88.1%), and OS 91.6%, 95% CI = (82.4%, 100%). EFS is significantly different between first and second CR (p = .0029). The pattern of relapse is predominantly (75%) of an isolated organ, mainly bone (54%). Univariate Cox models show prior history of relapse as the only statistically significant predictor of EFS but not OS. CONCLUSIONS: Consolidation with naxitamab and GM-CSF resulted in excellent survival rates for HR-NB patients in CR.

Functional neuroimaging in nonepileptiform electroencephalographic patterns in status epilepticus.

BACKGROUND: The diagnosis of nonconvulsive status epilepticus (NCSE) in patients with nonepileptiform EEG patterns remains a challenge. OBJECTIVE: To evaluate the usefulness of single photon emission computerized tomography (SPECT) and its quantification (QtSPECT) in the diagnosis of NCSE. METHODS: We retrospectively reviewed patients admitted with clinical suspicion of NCSE who underwent an HMPAO-SPECT simultaneously with scalp EEG showing nonepileptiform patterns, in a 5-year period. After a complete diagnostic workup, treatment, and clinical evolution, disregarding the SPECT results, patients were classified into confirmed NCSE (n = 11) and non-NCSE (n = 8). Then, we compared the EEG and SPECT results in both groups. RESULTS: Lateralized rhythmic delta activity (LRDA) was predominant in the NCSE group (45.4%, p = .045), while lateralized irregular slowing was observed equally in both groups. Patients with NCSE showed significant hyperperfusion compared with non-NCSE patients (p = .026). QtSPECT correctly classified 91% of patients in NCSE and 75% patients with non-NCSE (p = .006). CONCLUSIONS: Regional cerebral blood flow measured with SPECT could be useful in the diagnosis of NCSE in cases of an EEG pattern with lateralized slow activity and high clinical suspicion.

WT1-Mutant Wilms Tumor Progression Is Associated With Diverting Clonal Mutations of CTNNB1.

WT1-mutant Wilms tumors exhibit a high rate of concomitant CTNNB1 mutations, associated with activated Wnt signaling. Here, we show by laser and manual microdissection of different histologic cell types from 6 WT1-mutant tumor samples that 1 patient's tumor can contain up to 4 distinct mutations in CTNNB1 and/or WTX. Consecutive sections may also harbor different CTNNB1 mutations. The variability of activating CTNNB1 mutations demonstrates the multifocal nature of WT1-mutant Wilms tumors. As multiple independent tumors can occur in patients with constitutional WT1 mutations, they need to be surveyed more closely for tumor development.

Angioid streaks and obstructive sleep apnea syndrome: are they related?

BACKGROUND: Sleep apnea syndrome (OSAS) has been associated with different ocular manifestations including glaucoma, floppy eye syndrome, punctate keratitis, keratoconus, and optic neuropathy. Angioid streaks are mainly associated with pseudoxanthoma elasticum (PXE) although they can appear in other systemic conditions affecting the elastic fibers. METHODS: This is a prospective, cross-sectional study. A complete ophthalmic examination was performed in 92 patients undergoing overnight polysomnography for suspicion of OSAS. Diagnosis and classification of OSAS were made based on apnea-hypopnea index (AHI). Stereoscopic optic disc photographs were taken in all patients and independently evaluated by two ophthalmologists. Patients with angioid streaks were referred to a dermatologist for axillary skin biopsy in order to rule out pseudoxanthoma elasticum or other skin abnormalities. RESULTS: Bilateral angioid streaks were observed in three patients who had been diagnosed with severe OSAS (AHI > 30/h). No clinical features characteristic of pseudoxanthoma elasticum or other pathological skin signs were observed. Skin biopsies were normal for all three patients, supporting the diagnosis of idiopathic angioid streaks. One of the patients developed bilateral choroidal neovascularization secondary to the angioid streaks over subsequent years. CONCLUSIONS: In view of the low prevalence of idiopathic angioid streaks in the general population, the finding of angioid streaks in patients with severe OSAS suggests OSAS as a possible risk factor for its development. The hypothesis of a connective tissue abnormality that could explain an association between both entities deserves further elucidation.

Deep-intronic variants in CNGB3 cause achromatopsia by pseudoexon activation.

Our comprehensive cohort of 1100 unrelated achromatopsia (ACHM) patients comprises a considerable number of cases (~5%) harboring only a single pathogenic variant in the major ACHM gene CNGB3. We sequenced the entire CNGB3 locus in 33 of these patients to find a second variant which eventually explained the patients' phenotype. Forty-seven intronic CNGB3 variants were identified in 28 subjects after a filtering step based on frequency and the exclusion of variants found in cis with pathogenic alleles. In a second step, in silico prediction tools were used to filter out those variants with little odds of being deleterious. This left three variants that were analyzed using heterologous splicing assays. Variant c.1663-1205G>A, found in 14 subjects, and variant c.1663-2137C>T, found in two subjects, were indeed shown to exert a splicing defect by causing pseudoexon insertion into the transcript. Subsequent screening of further unsolved CNGB3 subjects identified four additional cases harboring the c.1663-1205G>A variant which makes it the eighth most frequent CNGB3 variant in our cohort. Compound heterozygosity could be validated in ten cases. Our study demonstrates that whole gene sequencing can be a powerful approach to identify the second pathogenic allele in patients apparently harboring only one disease-causing variant.