SMARCB1 deletion

Based on the morphologic, immunohistochemical, and molecular analyzes, the present case was difficult to classify into any of the existing entities. SMARCB1 deficiency might play a key role in the tumorigenesis.

We reported the first case of primary adenocarcinoma of the spermatic cord with SMARCB1 (INI-1) deficiency. This case contributes to the expanding understanding of rare neoplasms and underscores the importance of further research into therapeutic strategies targeting SMARCB1-deficient tumors.

Simvastatin was highly sensitive against MZ611ATRT cells and induced apoptosis (IC50 was 3.098 µM for MZ611ATRT, 41.88uM for U-87 MG, 23.34uM for IOMM-Lee, and 18.12uM for U-251 MG.). Pathways involved in cholesterol biosynthesis may be new targets for adjuvant therapy of AT/RT.

Postoperative adjuvant chemotherapy was given to three patients. AFP-producing adenocarcinoma is a rare subtype of gastric cancer, which can be combined with SWI/SNF complex deletion, and the pathomorphological manifestations are different from the classical SWI/SNF complex deletion of undifferentiated carcinoma with rhabdoid phenotype.

The original diagnosis was usually high-grade non-intestinal-type adenocarcinoma or high-grade myoepithelial carcinoma. A correct diagnosis of these aggressive tumors could lead to improved targeted therapies with potentially better overall disease-specific survival.

Research of INI1 deletion should be performed for undifferentiated carcinoma of young patients because of possibilities of molecular therapies such as autophagy inhibitors or proteasome inhibitors could be used in clinical trials.

We present this case as well as a review of the literature regarding etiologic associations with ES. Poster type: Poster Defense

This multiomics study supports the notion that P-ES and C-ES are distinct molecular entities, characterized by a different degree of phenotypic drift form the mesenchymal makeup and marked by different DNA methylation and miRNA:gene circuitries. The transcriptional profile of P-ES suggests that biology rather than anatomic location sustains its poorer outcome. Our study unveiled also novel immunohistochemical markers that might aid in the differential diagnosis of P-ES and C-ES, thus serving as potential tools of patient stratification in future studies.

Partial loss of SMARCB1/INI1, secondary to heterozygous deletion and/or copy number gain of SMARCB1, is not peculiar of aggressive forms, but can be identified by immunohistochemistry in a significant portion of conventional skull base chordomas, including the chondroid subtype. The variable protein expression does not appear to correlate with clinicopathological parameters, nor survival outcomes, but still, it could have therapeutic implications.

Patients who underwent GTR of these lesions showed improved survival rates. Recent advancements in NGS aided in the identification of diagnostic and therapeutic PIS-relevant targets.

Metastases exhibited a certain extent of genomic and transcriptomic diversity from primary PanNETs. TP53 and KRAS mutation in primary samples might associate with metastasis and contribute to a poorer prognosis. A high fraction of novel targetable alterations enriched in metastases deserves to be validated in advanced PanNETs.

CSF ctDNA could more sensitively detect molecular markers and metastasis-related mechanisms than tumor tissues in GCLM patients, and our study sheds light on utilizing CSF ctDNA in prognostic estimation and clinical assessment in GCLM.

Here we describe SMARCB1-negative PTCL-NOS as a potential new molecular subtype of PTCL-NOS significantly enriched in young patients. A strong concordance between naturally occurring SMARCB1-deficient PTCL in humans and in the targeted mouse model were found regarding epigenetic features. Our results provide a rationale for further investigation of potential HDACi combination therapies in SMARCB1-negative PTCL-NOS.

In each case, experts would combine conventional multimodal treatment concepts, including re-irradiation, with targeted therapy based on molecular genetic findings. International cooperative trials combining a (chemo-)therapy backbone with targeted therapy approaches for defined subgroups may help to gain valid clinical data and improve treatment in pediatric patients with recurrent/progressing HGG.

Partial loss of SMARCB1/INI1, secondary to heterozygous deletion and/or copy number gain of SMARCB1 , is not peculiar of aggressive forms, but can be identified by immunohistochemistry in in a significant portion of conventional and chondroid skull base chordomas. The different protein expression does not appear to correlate with clinicopathological parameters nor survival outcomes. However, it could still have therapeutic implications.

P2 | "Notably, a complete SMARCB1/INI1 deletion (targetable by tazemetostat) was identified... NGS in conjunction with OGM demonstrated improved detection of clinically actionable alterations for this patient. Thus, both tests should be routinely considered as a part of the diagnostic regimen to better characterize key mutations in rare tumors and uncover actionable targets for treatment. Combining multiple types of molecular analyses uncovered that this patient was eligible for a novel clinical trial."

No abstract available

Based on epigenetic characteristics, primary adult sellar SMARCB1/INI1-deficient tumors represent a subtype of ATRT with similar epigenetic characteristics of ATRT-MYC subgroup. Our findings suggest that DNA methylation profiling should be utilized for differential diagnosis for the majority of epithelioid sarcoma and (sellar) rhabdoid tumor.

The deletion of the SMARCB1/INI1 gene leads to activation of certain pathways, which can be targeted for treatment with the drug Tazemetostat... NGS in conjunction to OGM can provide improved detection of clinically relevant variants for genetic disease. Thus, both tests should be considered as a part of the diagnostic regimen to better characterize key mutations in rare tumors and uncover actionable targets for treatment.

This is the first cancer-related germline analysis with detailed clinical information reported in Japanese children with brain tumors. The prevalence was almost equivalent to that in white children.

SMARCB1 MLPA assay of blood showed no deletion. This cascade represents a novel, "four-hit" mechanism of SMARCB1 inactivation resulting in ATRT and the first known dual diagnosis of NF2 and ATRT.

These findings highlight that AT/RTs, potentially paradigmatic for other pediatric tumors with a low mutational load, present a variety of highly immunogenic HLA class I and class II peptides from canonical as well as non-canonical protein sources. Inclusion of such cryptic peptides into therapeutic vaccines would enable an optimized mapping of the tumor cell surface, thereby reducing the likelihood of immune evasion.

The initial diagnostic biopsy did not reveal rhabdoid cells while all metastatic foci showed cells with rhabdoid morphology in the autopsy specimens. Although this rhabdoid component resembled malignant rhabdoid tumor morphologically, molecular analyses failed to show mutations or deletions of SMARCB1.

Critical analysis of radiological and histopathological features, including necessary immunostains (brachyury and SMARCB1/INI1), is necessary for their timely diagnosis. These tumors show loss of SMARCB1/INI1 immunostaining and homozygous deletion of INI1/SMARCB1 gene.

Both poorly differentiated chordomas demonstrated a complex hyperdiploid genomic profile with gain of multiple chromosomes and homozygous deletion of SMARCB1. Our findings show that heterozygous deletion of SMARCB1 or the loss of chromosome 22 is a consistent abnormality in extra-axial chordoma and transformation to poorly differentiated chordoma is characterized by homozygous loss of SMARCB1 associated with genomic complexity and instability such as hyperdiploidy.

One patient had progressive disease while receiving the enhancer of zeste homolog 2 inhibitor tazemetostat. Overall, these findings suggest that vulvar tumors with pure yolk sac-like morphology may represent morphologic variants of SMARCB1-deficient tumors and not veritable germ cell neoplasia. This potential reclassification may have both prognostic and treatment implications and warrants study of additional extragonadal yolk sac tumors.

Overexpression of NRAS was sufficient to restore cellular proliferation, and MYC, a transcription factor downstream of NRAS, was bound to the HERV-K LTR significantly more in the absence of SMARCB1 expression in AT/RT cells. We show a mechanism by which these undifferentiated tumors remain pluripotent, and we demonstrate that their formation is aided by aberrant HML-2 activation, which is dependent on SMARCB1 and its interaction with MYC.

While the site of origin cannot be determined definitively, the highest tumor burden was in the orbit, making this the most likely primary site. Congenital orbital rhabdoid tumor is rare and only a few cases are reported in the literature.

These include immunohistochemical antibodies that represent reliable surrogates for the detection of gene fusions (e.g., STAT6, CAMTA1, FOSB, DDIT3) and more recently described breakpoint-specific antibodies (e.g., SS18-SSX, PAX3/7-FOXO1). Additionally, discussed are markers that correlate with the presence of gene amplifications (e.g., MDM2, CDK4), deletions (e.g., SMARCB1, SMARCA4), single nucleotide variants (e.g., G34W, K36M), aberrant methylation (H3K27me3), and increased expression as discovered through gene expression profiling (e.g., MUC4, DOG1, ETV4, NKX2.2, NKX3.1).

The patient completed four rounds of neoadjuvant therapy with ifosfamide, carboplatin, and etoposide in combination with 50 Gy radiation...He had considerable disease progression despite pembrolizumab and investigative therapies on early phase clinical trials... This case describes an AYA patient with a treatment-resistant soft tissue myoepithelial carcinoma and a previously unreported ARID1A mutation. ARID1A mutations have been described as potent oncogenic drivers in other tumor types and are reportedly resistant to platinum-based chemotherapy regimens. While we cannot establish clinical guidelines from a single case, our finding expands the molecular phenotype of this tumor, provides a potential mechanism for the observed resistance to platinum-based chemotherapy in a subset of cases, and highlights the need for a new therapeutic approach to this challenging diagnosis.

SDCS can be clinically aggressive, harbor SMARCB1 homozygous deletions or truncating SMARCB1 mutations associated with LOH, and can occur with or without UV-MS. Overall, SMARCB1 mutations in NMSC are rare with most being of undetermined significance and associated with retained INI1 and UV-MS.