Objective:To investigate the clinicopathological and molecular genetic characteristics of the neuroepithelial tumor with PATZ1 fusion (NET-PATZ1).Methods:Five cases of NET-PATZ1 diagnosed at the Sanbo Brain Hospital of Capital Medical University, Beijing, China from January 2020 to October 2024 were collected. The clinical, prognostic, imaging, histological and immunohistochemical features and the results of next-generation sequencing (DNA and RNA) of these 5 patients were collected and analyzed. Relevant literature was also reviewed for discussion.Results:Among the 5 cases, there were 4 females and 1 male, with a median age of 9.0 (6.5, 15.5) years. The tumors all occurred in the supratentorial cerebral hemispheres, including the frontal lobe, parietal lobe, lateral ventricle, and thalamus. There were diverse histological features. Two cases exhibited the characteristics of high-grade neuroepithelial tumors, while 3 cases showed those of low-grade neuroepithelial tumors. The tumor cells were mostly arranged in a rosette-like pattern around small blood vessel. The background was rich in vascular components or microvascular hyperplasia. Immunohistochemistry showed that the tumor cells diffusely expressed MAP2 and Vimentin, and had various expression of S-100 protein, GFAP, Olig2, NG2 and CD99, and cytoplasmic and perinuclear expression of Syn. At the genomic level, all cases had PATZ1 gene fusion variants, and the gene breakpoints were all located in exon 1. Four cases had fusion with the EWSR1 gene, and 1 case had fusion with the MN1 gene. The 5 patients all underwent craniotomy for tumor resection. The pathological diagnosis was NET-PATZ1. All cases had no recurrence or metastasis at the end of follow-up except that Case 3 developed spinal cord metastasis 11 months after the surgery.Conclusions:NET-PATZ1 is commonly found in children and adolescents, with diverse histological features. The tumor cells typically arrange in rosette-like patterns, and the background is rich in vascular components or microvascular hyperplasia. Tumor cells express glial cell-related markers to varying degrees, and co-expression of NG2 and CD34 is suggestive of its diagnosis. The establishment of a pathological diagnosis relies on the detection of PATZ1 fusion variations through genetic testing or a DNA methylation profile of NET-PATZ1.

Objective:To investigate the clinicopathological characteristics and differential diagnosis of DICER1-mutant primary intracranial sarcoma.Methods:Five cases of DICER1-mutant primary intracranial sarcoma at Sanbo Brain Hospital, Capital Medical University, Beijing, China during May 2013 to November 2024 were collected. The clinical and imaging data were retrieved. Histological evaluation, immunohistochemical staining and next generation sequencing were performed. Additionally, a literature review was conducted.Results:All five DICER1-mutant primary intracranial sarcomas were located in the supratentorial region, with one case involving the basal ganglia. There were two males and three females. The median age at diagnosis was 25 (14.0, 30.5) years. Morphologically, they were characterized by high-grade spindle cell sarcoma, with brisk mitotic activity and cytoplasmic eosinophilic globules. Myxoid degeneration, necrosis, and invasion into surrounding brain tissue were observed in some cases. The tumor cells showed diffuse staining of vimentin and variable expression of myogenic marker (desmin), with or without focal MyoD1 and/or Myogenin expression. Four tumors exhibited diffuse, strong expression of TLE1 and p53, while only three tumors showed loss of ATRX (nuclear) expression. Two cases showed mosaic loss of H3K27me3 expression in neoplastic cells. The Ki-67 proliferation index was high (40%-80%). Various neuronal markers, such as synaptophysin, NF, SOX2 and MAP2, were expressed in all tumor samples. Genetically, all tumors samples harbored biallelic abnormalities of DICER1. One was a hotspot missense mutation in the RNase Ⅲb domain within exon 25 on one allele (p.E1813 or p.D1810), while the other allele had mutations including a germline mutation in one case, a somatic mutation in two cases, and a copy number deletion in two cases. In addition, these sarcomas showed alterations in TP53 (4/5), ATRX (3/5), and the genes of the mitogen-activated protein kinase pathway (3/5). Finally, all five cases were diagnosed as DICER1-mutant primary intracranial sarcoma. All patients underwent craniotomy that led to complete tumor resection. Three patients received adjuvant radiotherapy and chemotherapy, with progression-free survival time of 28, 48, and 50 months, respectively. Patient 2 succumbed to the tumor after 3 months post-surgery due to rapid progression and tumor dissemination. Patient 5 was lost to follow-up 3 months after the surgery.Conclusions:DICER1-mutant primary intracranial sarcoma is a newly defined tumor entity in the fifth edition of the World Health Organization Classification of Central Nervous System Tumors, and commonly occurs in children and young adults. High-grade malignant spindle cells are their typical morphological feature. Eosinophilic cytoplasmic globules and myogenic differentiation can help establish the diagnosis. This study suggests that DICER1-mutant primary intracranial sarcomas exhibit immunophenotypic neuronal differentiation. Rendering the diagnosis of DICER1-mutant primary intracranial sarcoma largely relies on detecting DICER1 pathogenic alterations or DNA methylation profiling.

Objective:To investigate the clinicopathological and molecular genetic characteristics of the neuroepithelial tumor with PATZ1 fusion (NET-PATZ1).Methods:Five cases of NET-PATZ1 diagnosed at the Sanbo Brain Hospital of Capital Medical University, Beijing, China from January 2020 to October 2024 were collected. The clinical, prognostic, imaging, histological and immunohistochemical features and the results of next-generation sequencing (DNA and RNA) of these 5 patients were collected and analyzed. Relevant literature was also reviewed for discussion.Results:Among the 5 cases, there were 4 females and 1 male, with a median age of 9.0 (6.5, 15.5) years. The tumors all occurred in the supratentorial cerebral hemispheres, including the frontal lobe, parietal lobe, lateral ventricle, and thalamus. There were diverse histological features. Two cases exhibited the characteristics of high-grade neuroepithelial tumors, while 3 cases showed those of low-grade neuroepithelial tumors. The tumor cells were mostly arranged in a rosette-like pattern around small blood vessel. The background was rich in vascular components or microvascular hyperplasia. Immunohistochemistry showed that the tumor cells diffusely expressed MAP2 and Vimentin, and had various expression of S-100 protein, GFAP, Olig2, NG2 and CD99, and cytoplasmic and perinuclear expression of Syn. At the genomic level, all cases had PATZ1 gene fusion variants, and the gene breakpoints were all located in exon 1. Four cases had fusion with the EWSR1 gene, and 1 case had fusion with the MN1 gene. The 5 patients all underwent craniotomy for tumor resection. The pathological diagnosis was NET-PATZ1. All cases had no recurrence or metastasis at the end of follow-up except that Case 3 developed spinal cord metastasis 11 months after the surgery.Conclusions:NET-PATZ1 is commonly found in children and adolescents, with diverse histological features. The tumor cells typically arrange in rosette-like patterns, and the background is rich in vascular components or microvascular hyperplasia. Tumor cells express glial cell-related markers to varying degrees, and co-expression of NG2 and CD34 is suggestive of its diagnosis. The establishment of a pathological diagnosis relies on the detection of PATZ1 fusion variations through genetic testing or a DNA methylation profile of NET-PATZ1.

Objective:To investigate the clinicopathological characteristics and differential diagnosis of DICER1-mutant primary intracranial sarcoma.Methods:Five cases of DICER1-mutant primary intracranial sarcoma at Sanbo Brain Hospital, Capital Medical University, Beijing, China during May 2013 to November 2024 were collected. The clinical and imaging data were retrieved. Histological evaluation, immunohistochemical staining and next generation sequencing were performed. Additionally, a literature review was conducted.Results:All five DICER1-mutant primary intracranial sarcomas were located in the supratentorial region, with one case involving the basal ganglia. There were two males and three females. The median age at diagnosis was 25 (14.0, 30.5) years. Morphologically, they were characterized by high-grade spindle cell sarcoma, with brisk mitotic activity and cytoplasmic eosinophilic globules. Myxoid degeneration, necrosis, and invasion into surrounding brain tissue were observed in some cases. The tumor cells showed diffuse staining of vimentin and variable expression of myogenic marker (desmin), with or without focal MyoD1 and/or Myogenin expression. Four tumors exhibited diffuse, strong expression of TLE1 and p53, while only three tumors showed loss of ATRX (nuclear) expression. Two cases showed mosaic loss of H3K27me3 expression in neoplastic cells. The Ki-67 proliferation index was high (40%-80%). Various neuronal markers, such as synaptophysin, NF, SOX2 and MAP2, were expressed in all tumor samples. Genetically, all tumors samples harbored biallelic abnormalities of DICER1. One was a hotspot missense mutation in the RNase Ⅲb domain within exon 25 on one allele (p.E1813 or p.D1810), while the other allele had mutations including a germline mutation in one case, a somatic mutation in two cases, and a copy number deletion in two cases. In addition, these sarcomas showed alterations in TP53 (4/5), ATRX (3/5), and the genes of the mitogen-activated protein kinase pathway (3/5). Finally, all five cases were diagnosed as DICER1-mutant primary intracranial sarcoma. All patients underwent craniotomy that led to complete tumor resection. Three patients received adjuvant radiotherapy and chemotherapy, with progression-free survival time of 28, 48, and 50 months, respectively. Patient 2 succumbed to the tumor after 3 months post-surgery due to rapid progression and tumor dissemination. Patient 5 was lost to follow-up 3 months after the surgery.Conclusions:DICER1-mutant primary intracranial sarcoma is a newly defined tumor entity in the fifth edition of the World Health Organization Classification of Central Nervous System Tumors, and commonly occurs in children and young adults. High-grade malignant spindle cells are their typical morphological feature. Eosinophilic cytoplasmic globules and myogenic differentiation can help establish the diagnosis. This study suggests that DICER1-mutant primary intracranial sarcomas exhibit immunophenotypic neuronal differentiation. Rendering the diagnosis of DICER1-mutant primary intracranial sarcoma largely relies on detecting DICER1 pathogenic alterations or DNA methylation profiling.

Objective:To deeply understand the real experience of young and middle-aged lymphoma patients returning to society.Methods:From August to September 2021, 17 young and middle-aged lymphoma patients admitted to the Department of Hematology of the First Affiliated Hospital with Nanjing Medical University were selected as the research object by objective sampling. Phenomenological research method was using to conduct face-to-face in-depth interviews. Colaizzi 7-step analysis method was used to summarize, analyze and refine the theme.Results:A total of 3 first-level themes and 10 second-level themes were extracted. Among them, the willingness to return to society included firm willingness of social return and negative attitude of social return. The scope of social return included returning to work, interpersonal communication, family responsibilities, leisure and entertainment and lifestyle. The influencing mechanism of social return was composed of disease and treatment factors, mental factors, external support and economic capacity.Conclusions:The experience of young and middle-aged lymphoma patients returning to society is a dynamic change process in many aspects. In the future, it is necessary to further explore the status quo of social return of such groups and explore the influencing factors and change tracks of heterogeneity.