The rhabdoid variant of adrenocortical carcinoma-Report of three cases and literature review

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy. Extensive rhabdoid morphology in ACC has been described recently in very few cases. The proportion of rhabdoid morphology and the role of SMARCB1/ INI1 expression in these tumor cells to diagnose the specific variant is not described in the literature. We reviewed the clinicopathological features of nine cases of adrenocortical neoplasm. Out of which, three cases of ACC showed predominant rhabdoid morphology. Large discohesive cells with abundant cytoplasm containing eosinophilic inclusions, eccentric vesicular nucleus, and prominent nucleoli. INI1 immunostain was retained in all cases. We reported the rhabdoid variant of ACC, a novel entity, and its diagnostic approach from their histological mimickers. Identifying more cases of this entity will help to clearly understand the pathogenesis, biologic behaviour, and any specific molecular alterations in the future.

SMARCB1 (INI-1) – Deficient sinonasal carcinoma: Report of two cases

SMARCB1 (INI-1)-deficient sinonasal carcinoma is a rare, poorly differentiated carcinoma defined by complete loss of tumor suppressor gene SMARCB1 (INI-1) within the neoplastic cell nuclei demonstrated by the immunohistochemical stain. SMARCB1 (INI-1) gene inactivation has been implicated in the pathogenesis of a diverse group of malignant neoplasms that tend to share “rhabdoid” morphology. SMARCB1 (INI-1)-deficient sinonasal carcinoma was first reported by Agaimy et al. in 2014. These tumors are often basaloid with focal rhabdoid differentiation, prominent necrosis, increased mitotic activity, and aggressive behavior. Other than being INI-1 and NUT negative, they are positive for pancytokeratin and express variable immunoreactivity for squamous markers like p63 and neuroendocrine markers like synaptophysin. Most patients present with locally advanced disease and hence a combination of chemotherapy, radiotherapy, and surgery is usually recommended.

Extrarenal rhabdoid tumor of anterior mediastinal location / Tumor rabdoide extrarrenal de localización mediastinal anterior

Abstract Background: Rhabdoid tumors are malignant neoplasms of low prevalence, aggressive behavior, and high mortality. They were initially described as renal tumors, although tumors with the same histopathological and immunohistochemical characteristics have been discovered in other locations, mainly in the central nervous system. Few cases of mediastinal location have been reported internationally. This work aimed to describe the case of a mediastinal rhabdoid tumor. Case report: We describe the case of an 8-month-old male patient admitted to the pediatric department with dysphonia and laryngeal stridor progressing to severe respiratory distress. Contrast-enhanced computed tomography of the thorax showed a large mass with homogeneous soft tissue density, and smooth and well-defined borders, with suspicion of malignant neoplasm. Due to the oncological emergency compressing the airway, empirical chemotherapy was initiated. Subsequently, the patient underwent incomplete tumor resection due to its invasive nature. The pathology report showed morphology compatible with a rhabdoid tumor, which immunohistochemical and genetic studies corroborated. Chemotherapy and radiotherapy to the mediastinum were administered. However, the patient died three months after the initial treatment due to the aggressive behavior of the tumor. Conclusions: Rhabdoid tumors are aggressive and malignant entities difficult to control and have poor survival. Early diagnosis and aggressive treatment are required, although the 5-year survival does not exceed 40%. It is necessary to analyze and report more similar cases to establish specific treatment guidelines.

Resumen Introducción: Los tumores rabdoides son neoplasias malignas de baja prevalencia, con comportamiento agresivo y alta mortalidad. Inicialmente fueron descritos como renales, aunque posteriormente se han descrito tumores con las mismas características histopatológicas e inmunohistoquímicas en otros sitios, principalmente en el sistema nervioso central. Internacionalmente se han descrito pocos casos de localización mediastinal. El objetivo del presente trabajo fue describir el caso de un tumor rabdoide de localización mediastinal. Caso clínico: Se presenta el caso de un paciente de sexo masculino de 8 meses de edad que ingresó al servicio de pediatría con disfonía y estridor laríngeo que progresó a dificultad respiratoria severa. En la tomografía computarizada contrastada de tórax se observó una gran masa homogénea con densidad de tejidos blandos, de bordes lisos y bien definidos, por lo que se sospechó una neoplasia maligna. Debido a la urgencia oncológica compresiva de la vía aérea se inició con un esquema empírico de quimioterapia. Posteriormente se sometió a resección tumoral incompleta por carácter invasor. El reporte de patología mostró morfología compatible con un tumor rabdoide, el cual se corroboró con estudios de inmunohistoquímica y genética. Se administró un esquema de quimioterapia y radioterapia al mediastino. Sin embargo, el paciente falleció a los 3 meses del inicio de tratamiento debido al comportamiento agresivo del tumor. Conclusiones: Los tumores rabdoides son entidades agresivas y malignas de difícil control y con pobre supervivencia. A pesar de que se requiere un diagnóstico precoz y un tratamiento agresivo, no se ha logrado la supervivencia a 5 años mayor al 40%. Es necesario analizar una mayor cantidad de casos para establecer guías específicas de tratamiento.

Melanoma primario maligno variedad rabdoide. A Propósitode un caso / Malignant primary melanoma rhabdoid variety. about a case

Resumen El melanoma primariovariedad rabdoide es unapresentación pocofrecuente.Reconocido como un subtipo histopatológico distinto de melanoma maligno generalmente observado en tumores metastásicos o recurrentes.El diagnóstico definitivo requiere el estudio de inmunomarcación y la identificación de células neoplásicas con marcadores melanocíticos. Clínicamente se han reportado mayormente de tipo nodular y amelanótico.

Summary Rhabdoid melanoma has been recognized as a histopathological subtype of malignant melanoma. It generally presents as a recurrent tumor, so its presentation as a primary lesion is infrecuent.Definitive diagnosis requires the study of immunostaining and the identification of neoplastic cells with melanocytic markers. Clinically, mostly nodular and amelanotic types have been reported.

Malignant chondroid syringoma: An unusual scalp tumor

Chondroid syringomas are similar to mixed parotid tumors and present in both benign and malignant forms. Malignant chondroid syringoma (MCS) is a rare skin tumor that has a predilection for extremities, particularly in young women. It is even rarer to present as a scalp tumor with very few reported cases in the literature. We present a middle-aged woman, with a history of increasing fatigability of her right arm for the past 3 months who, on examination, was found to have scalp swelling and matted right posterior triangle lymph nodes. The working diagnosis on her was a large sebaceous cyst with secondary in the neck from an occult primary/non-Hodgkin抯 lymphoma. Preliminary fine-needle aspiration was inconclusive. Imaging followed by wide excision of the tumor and the nearby occipital node was done. The final histopathological diagnosis was MCS with secondary in the lymph node. These tumors are aggressive and metastasize early. Radical surgery is the only hope of cure as adjuvant treatment is yet to be standardized

Embryonal tumors in the WHO CNS5 classification: A Review

Embryonal tumors are a heterogenous group of neoplasms mostly defined by recurrent genetic driver events. They have been, previously, broadly classified as either medulloblastoma or supratentorial primitive neuroectodermal tumors (PNETs). However, the application of DNA methylation/gene expression profiling in large series of neoplasms histologically defined as PNET, revealed tumors, which showed genetic events associated with glial tumors. These findings led to the definitive removal of the term “PNET” in the 2016 World Health Organization (WHO) classification of CNS tumors. Moreover, further studies on a large scale of methylation profiling have allowed the identification of new molecular-defined entities and have largely influenced the 5th edition of the WHO classification of CNS tumors (WHO CNS5) for both medulloblastomas and other CNS embryonal tumors. The importance of molecular characteristics in CNS embryonal tumors is well represented by the identification of different molecular groups and subgroups in medulloblastoma. So, in the CNS5, the emerged group 3 and group 4 belong to the classification, and the four molecular and morphologic types are now combined into a unique section. Among other embryonal tumors, two new recognized entities are introduced in CNS5: CNS neuroblastoma, FOXR2-activated, and CNS tumor with BCOR internal tandem duplication (ITD). Embryonal tumor with multilayered rosettes (ETMR), already present in the previous classification now has a revised nomenclature as a result of the new DICER1 alteration, additional to the formerly known C19MC. Regarding atypical teratoid/rhabdoid tumor (AT/RT), three molecular subgroups are recognized in CNS5. The combination of histopathological and molecular features reflects the complexity of all these tumors and gives critical information in terms of prognosis and therapy. This encourages the use of a layered diagnostic report with the integrated diagnosis at the top, succeeded by layers including the histological, molecular, and other essential details.

Congenital malignant rhabdoid tumor in a fetal neck: a case report / 中华围产医学杂志

We report the clinical characteristics of congenital malignant rhabdoid tumor (MRT) of the neck in a fetus. Prenatal ultrasound and MRI at 33 +4 and 34 weeks gestation revealed a round solid mass on the right side of the fetus' neck. An initial differential diagnosis was between neuroblastoma and vascular malformation. Re-examination with ultrasound at 36 gestational weeks revealed an enlarged fetal neck mass, with concomitant multiple subcutaneous solid masses all over his body, right-side hydrothorax, and abnormal liver echo, which were highly suspicious of metastasis of a malignant tumor. The baby boy was delivered by cesarean section at 37 weeks of gestation with a normal Apgar score and slight shortness of breath. Physical examination showed scattered lesions in the neck, armpits, and limbs, etc. The condition of the infant deteriorated rapidly with the increasing number and volume of the masses after admission. The boy was confirmed as MRT (stage Ⅳ) by pathological biopsy on the left upper arm and died on postnatal day 10 after treatment was withdrawn.

Congenital presentation of synchronous Atypical Teratoid Rhabdoid Tumor and Malignant Rhabdoid Tumor of the urinary bladder in a term infant

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare central nervous system (CNS) tumor diagnosed primarily in infants and usually portends a poor prognosis. Despite being the most common embryonal tumor in children less than 1 year old, diagnosis is difficult to make based on clinical findings or imaging alone. A complete diagnosis of AT/RT requires identification of loss of integrase interactor 1 (INI1) protein or the SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily b, member 1 (SMARCB1) gene, in its most common presentation. Moreover, their presentation with other primary rhabdoid tumors in the body raises significant suspicion for rhabdoid tumor predisposition syndrome (RTPS). We report a case of a one-month-old infant admitted for worsening emesis and failure to thrive, who was later found to have brain and bladder masses on radiologic imaging. Autopsy with subsequent immunoprofile and molecular testing were crucial in establishing the absence of INI1 nuclear expression and possible homozygous deletion of SMARCB1 in the urinary bladder tumor tissue. Sequencing of the peripheral blood demonstrated probable single copy loss at the SMARCB1 locus. The constellation of findings in tumor and peripheral blood sequencing suggested the possibility of germline single copy SMARCB1 loss, followed by somatic loss of the remaining SMARCB1 allele due to copy neutral loss-of-heterozygosity. Such a sequence of genetic events has been described in malignant rhabdoid tumors (MRT). Dedicated germline testing of this patient's family members could yield answers as to whether rhabdoid tumor predisposition syndrome will continue to have implications for the patient's family.

Clinicopatholoical Spectrum Of Embryonal Brain Tumors And Their Prognostic Significance – A Three Years Institutional Study At A Tertiary Care Hospital In South India

BACKGROUND:Central nervous system tumors constitute second most common paediatric cancers.Emyonal tumors are neoplasms of immature cells resembling primitive neuroepithelium.All are similarly aggressive and have a tendency to disseminate throughout CNS.Therefore identification of specific subtype helps in prognosis evaluation,to avoid unnecessary treatment related neurotoxicity and further treatment implications. METHODS: This is a retrospective study conducted at The Department of neuropathology, Institute of neurosurgery MMC/RGGGH from January 2015 to December 2017.A total of 34 cases of Emyonal tumors were reviewed during this period.Among which Medulloblastoma was reclassified histopathologically based upon the World Health Organisation 2016 classification of CNS tumors.Data on clinical presentation and radiological features of all cases were collected from patients records.In all cases gross features were recorded during grossing of the resected tumors.The tissue sections were processed and stained as per standard protocols. IHC markers were done in deserving cases .Age predilection,Sex Predilection,Tumor location,Comparison with squash and Histological grade in relation to age of emyonal tumors studied. RESULTS:Out of 1422 cases evaluated in adults emyonal tumors comprised 0.21%(3 cases).Out of 150 cases evaluated in chidren aged 16 years emyonal tumors comprised 20.6%(31 cases).Sex ratio(males to females) 2:1 males outnumbering females.94.11%(32 cases) of emyonal tumors presented as posterior fossa tumors,2.94%(1 case) presented as hypothalamic SOL,2.94%(1 case) presented with multiple lesions in spine and cranium–This was a rare case of Atypical Teratoid /Rhabdoid tumor presented with drop metastasis.5.88%(2 cases) presented as recurrent tumors.82.3%(28 cases) presented histologically as classic medulloblastomas,2.94%(1 case) presented as Anaplastic/Large cell type, 2.94%(1 case) presented as Desmoplastic type,11.76%(4 cases) presented as Atypical Teratoid/Rhabdoid tumor.Most commonly affected age group is 6–10 years comprising 50%(17 cases),20.5%(7 cases) affecting 0–5 years, 20.5%(7 cases) affecting 11–16 years. CONCLUSION:Emyonal tumors are highly malignant tumors affecting children from early infancy to adolescence .Because of efforts to avoid craniospinal irradiation in an attempt to lessen treatment related neurotoxicity,diagnosis and management is very important.

Clinical and image analysis of extrarenal non-central nervous system malignant rhabdoid tumors / 中华实用儿科临床杂志

Objective To demonstrate the clinical and imaging features of extrarenal malignant rhabdoid tumor (MRT) outside the central nervous system(CNS) in children and to raise awareness of the disease.Methods A retrospective database review was made of 15 patients diagnosed with extrarenal MRT outside the CNS in Beijing Children's Hospital,Capital Medical University from April 2008 to February 2017.The ultrasound,CT and magnetic resonance imaging(MRI) examinations were performed in 12,10 and 7 cases,respectively,and the clinical and imaging features were analyzed.Results The 15 patients included 8 boys and 7 girls.The age at presentation varied from 11 days to 12 years and 9 months old with a median age of 4 years old.The primary tumors were predominant solid masses,most of which were irregular,with a length of 2.20-11.70 cm [(5.87 ± 2.57) cm].The primary tumors had variable locations,relatively tended to occur in the head and neck region (6 cases) and the mediastinum (4 cases).On ultrasound,11 cases of the tumors were heterogeneous,7 cases of the tumors were accompanied with cystic change,and the solid part was mainly hypoechoic.On CT,density of 6 cases of the tumors was uneven,3 cases presented cystic change,4 cases were with calcification,and the solid part had slightly low density,with enhancement of different degrees.On MRI,7 cases of tumors showed mixed signal,5 cases with cystic change of different degrees;the solid part mainly showed isointensity or slightly hypointensity on T1 weighted image and hyperintensity or slightly hyperintensity on T2 weighted image,with restricted diffusion and predominantly heterogeneous enhancement.Medical imaging showed definite hemorrhage within tumors in 5 patients,and metastases occurred in 6 patients at the time of diagnosis,the adjacent bone destruction occurred in 3 patients,and the tumor tissue of 3 patients extended into the spinal canal.Conclusion Extrarenal MRT outside the CNS is more common in preschool kids,most of which are large and heterogeneous solid masses,often with cystic change,sometimes with hemorrhage and calcification;the solid part with restricted diffusion and inhomogeneous enhancement.Some of the patients had metastasis and local invasion.

Atypical Teratoid/Rhabdoid Tumor Presenting as a Cutaneous Lesion: A Case Report / 대한피부과학회지

An atypical teratoid/rhabdoid tumor (AT/RT) is a rare malignancy occurring in the first few years of life. This tumor shows rapid growth, a poor response to treatment, and poor prognosis. Cutaneous metastases presents as hamartomatous lesions mimicking skin tags. Immunohistochemical examination shows varied patterns of expression based on the sites of the body affected. Integrase interactor-1 (INI-1) gene sequencing and loss of expression of INI-1 observed with immunostaining can confirm AT/RT. In our patient, the skin lesion was identified at birth. Histopathological examination of the skin lesion could not establish an accurate diagnosis. Two months later, the patient presented with a brain tumor. Immunohistochemical examination of the brain lesion revealed complete loss of INI-1 expression in tumor cells, and the lesion was diagnosed as AT/RT. After that, we can detect the loss of INI-1 expression in the skin on the back. We report a rare case of AT/RT affecting the brain with cutaneous metastasis diagnosed with immunohistochemical staining.

Supratentorial Atypical Rhabdoid Teratoid Tumor ­ A Case Report

Atypical rhabdoid teratoid tumors (ARTTs) are rare embryonic tumors, usually localized in the posterior fossa and diagnosed in children under 3 years-old. The treatment includes surgical resection, radio and chemotherapy, and the prognostic is unfavorable, with an average median survival of 1 year. We present the case of a 3-year-old patient, with history of headache and vomiting, followed by absence seizures, temporal automatism, syncope accompanied by sialorrhea and sphincteric loss succeeded by a postictal period. Surgical excision was performed and the anatomopathological study confirmed ARTT. The ARTTs are embryonic tumors, a category in which medulloblastoma and primitive neuroectodermal tumors (PNETs) represent the most common central nervous system (CNS) malignancies in childhood.

Tumores teratóides rabdóides atípicos (TTRA) são tumores embrionários raros, geralmente localizados na fossa posterior e diagnosticados em crianças com menos de 3 anos de idade. O tratamento inclui ressecção cirúrgica, radio e quimioterapia. Contudo, o prognóstico é desfavorável, com uma sobrevida média de 1 ano. Apresentamos o caso de um paciente de 3 anos de idade, com quadro de cefaléia e vômitos, companhados por automatismo temporal e perda de consciência, seguidos por período pós-ictal. A ressonância nuclear magnética (RNM) do encéfalo evidenciou lesão frontal compatível com tumor intra-axial, efeito de massa local e invasão do corpo caloso. Foi realizada excisão cirúrgica, e o estudo anatômico-patológico confirmou TTRA. Os TTRA são tumores embrionários, categoria na qual o meduloblastoma e os tumores neuroectodermais primitivos representam as malignidades mais comuns no sistema nervoso central de crianças.

Primary uterine angiosarcoma with “rhabdoid morphology”: A case report

@#Introduction: Primary uterine angiosarcoma is a very rare tumour, with only 23 cases described till now. It is a malignant tumour with cells variably recapitulating the morphologic features of an endothelium and expressing immunohistochemical markers of endothelial cells. In general, it is a bulky neoplasm and frequently is at advance stage of disease at presentation. In general, patients with uterine angiosarcoma tend to have a poorer prognosis, mostly related to the aggressive nature and the metastatic potential of these tumours. Case report: We report a rare case of primary uterine angiosarcoma with unusual rhabdoid morphology in a 41-year-old female, who underwent radical hysterectomy and died of disease after 4 months of treatment. Discussion: We described the differential diagnosis of primary angiosarcoma of the uterus that can pose a diagnostic challenge.

Atypical Teratoid Rhabdoid Tumour : From Tumours to Therapies

Atypical teratoid rhabdoid tumours (ATRTs) are the most common malignant central nervous system tumours in children ≤1 year of age and represent approximately 1–2% of all pediatric brain tumours. ATRT is a primarily monogenic disease characterized by the bi-allelic loss of the SMARCB1 gene, which encodes the hSNF5 subunit of the SWI/SNF chromatin remodeling complex. Though conventional dose chemotherapy is not effective in most ATRT patients, high dose chemotherapy with autologous stem cell transplant, radiotherapy and/or intrathecal chemotherapy all show significant potential to improve patient survival. Recent epigenetic and transcriptional studies highlight three subgroups of ATRT, each with distinct clinical and molecular characteristics with corresponding therapeutic sensitivities, including epigenetic targeting, and inhibition of tyrosine kinases or growth/lineage specific pathways.

Malignant Brain Tumours in Children : Present and Future Perspectives

In contrast to many of the malignant tumors that occur in the central nervous system in adults, the management, responses to therapy, and future perspectives of children with malignant lesions of the brain hold considerable promise. Within the past 5 years, remarkable progress has been made with our understanding of the basic biology of the molecular genetics of several pediatric malignant brain tumors including medulloblastoma, ependymoma, atypical teratoid rhabdoid tumour, and high grade glioma/diffuse intrinsic pontine glioma. The recent literature in pediatric neuro-oncology was reviewed, and a summary of the major findings are presented. Meaningful sub-classifications of these tumors have arisen, placing children into discrete categories of disease with requirements for targeted therapy. While the mainstay of therapy these past 30 years has been a combination of central nervous system irradiation and conventional chemotherapy, now with the advent of high resolution genetic mapping, targeted therapies have emerged, and less emphasis is being placed on craniospinal irradiation. In this article, the present and future perspective of pediatric brain malignancy are reviewed in detail. The progress that has been made offers significant hope for the future for patients with these tumours.

Atypical Teratoid Rhabdoid Tumour : From Tumours to Therapies

Atypical teratoid rhabdoid tumours (ATRTs) are the most common malignant central nervous system tumours in children ≤1 year of age and represent approximately 1–2% of all pediatric brain tumours. ATRT is a primarily monogenic disease characterized by the bi-allelic loss of the SMARCB1 gene, which encodes the hSNF5 subunit of the SWI/SNF chromatin remodeling complex. Though conventional dose chemotherapy is not effective in most ATRT patients, high dose chemotherapy with autologous stem cell transplant, radiotherapy and/or intrathecal chemotherapy all show significant potential to improve patient survival. Recent epigenetic and transcriptional studies highlight three subgroups of ATRT, each with distinct clinical and molecular characteristics with corresponding therapeutic sensitivities, including epigenetic targeting, and inhibition of tyrosine kinases or growth/lineage specific pathways.

Malignant Brain Tumours in Children : Present and Future Perspectives

In contrast to many of the malignant tumors that occur in the central nervous system in adults, the management, responses to therapy, and future perspectives of children with malignant lesions of the brain hold considerable promise. Within the past 5 years, remarkable progress has been made with our understanding of the basic biology of the molecular genetics of several pediatric malignant brain tumors including medulloblastoma, ependymoma, atypical teratoid rhabdoid tumour, and high grade glioma/diffuse intrinsic pontine glioma. The recent literature in pediatric neuro-oncology was reviewed, and a summary of the major findings are presented. Meaningful sub-classifications of these tumors have arisen, placing children into discrete categories of disease with requirements for targeted therapy. While the mainstay of therapy these past 30 years has been a combination of central nervous system irradiation and conventional chemotherapy, now with the advent of high resolution genetic mapping, targeted therapies have emerged, and less emphasis is being placed on craniospinal irradiation. In this article, the present and future perspective of pediatric brain malignancy are reviewed in detail. The progress that has been made offers significant hope for the future for patients with these tumours.

Renal Tumors in Children / 임상소아혈액종양

Pediatric renal tumors represent a diverse group, which include Wilms' tumor (WT), renal cell carcinoma (RCC), clear cell sarcoma of the kidney (CCSK), congenital mesoblastic nephroma, malignant rhabdoid tumor of the kidney (MRTK) and primitive neuroectodermal tumor. WT (85%) and RCC (8%) are the most prevalent types. WT predominates among the 1- to 10-year age group, but RCC exceeds WT in children over age 10 years. Pediatric renal tumors are genetically, histologically and clinically heterogeneous. The overall survival for children with localized WT is currently more than 90%, whereas poorer survival rates are observed for anaplastic WT, metastatic WT, metastatic CCSK, MRTK, metastatic RCC and relapsed WT. Therefore risk-stratified treatment is important to minimize treatment morbidity while preserving survival. This review focuses on distinct characteristics of each tumor type and optimal stratified treatment.

Loss of expression of the Neural Cell Adhesion Molecule 1 (NCAM1) in atypical teratoid/rhabdoid tumors: a new diagnostic marker?

Background: Atypical teratoid/rhabdoid tumors (AT/RT) are aggressive embryonal tumors of the central nervous system. They are largely characterized by inactivating mutations of the SMARCB1 tumor suppressor gene. AT/RT patients have a very poor prognosis and no standard therapeutic protocol has been defined yet. Recently, multimodal therapy with multiple drug combinations has slightly improved the overall survival, however drug toxicity remains high. In this scenario, a better understanding of the pathophysiology of the disease is needed. Methods: We evaluated the gene expression profile of AT/RT samples to find new genetic factors contributing to the pathophysiology of the disease. We found target genes significantly differentially expressed between AT/RT and medulloblastoma (MB), the most common embryonal brain tumor. The mRNA expression was validated by quantitative real-time PCR and, at the protein level, expression was validated by immunohistochemistry in an independent set of tumors. Results: The Neural cell adhesion molecule 1 (NCAM1) gene was found to be consistently downregulated in AT/RT samples when compared to MB and normal brain tissue. Immunohistochemistry showed that the expression of NCAM1 in AT/RT was significantly lower than that of MB. Conclusion: NCAM1 is an important molecule involved in neuron-to-neuron and neuron-to-muscle adhesion during development. Downregulation of NCAM1 has been implicated in several human cancers suggesting that it might have a tumor repressor role. In this study we found a significantly reduced expression of NCAM1 in AT/RT when compared to MB and we suggest that this feature can be used as a diagnostic marker, along with demonstration of SMARCB1 (INI1) or SMARCA4 (BRG1) inactivation. The roles of NCAM1 in the pathophysiology of AT/RT are still to be determined (AU)

Renal rhabdoid synovial sarcoma: report of a case with literature review / 临床与实验病理学杂志

Purpose To report a rare case of renal rhabdoid synovial sarcoma and review the literature,in order to improve the realization for this disease and reduce misdiagnosis.Method The clinicopathological data of 1 case rhabdoid renal synovial sarcoma were retrospectively analyzed.The tumors were examined by immunohistochemical of EnVision two-step staining and FISH,the related literatures were reviewed.Result A 31-year-old male patient accepted the right kidney radical operation in November 2014 after imaging examination of right kidney tumor.Microscopically,the tumor cells showed short spindle cells with rich cytoplasm and eosinophilic bodies in the cytoplasm.The pathological diagnosis is the renal rhabdoid tumor for this time.The patient was found a tumor between the liver and the diaphragm by imaging examination in October 2015.The second operation was carried out successfully.Microscopically,the tumor cells were spindle with little cytoplasm and without eosinophilic bodies in the cytoplasm.It was a typical synovial sarcoma in morphology for this time.Immunohistochemical staining showed positive for vimentin,EMA,CD56,and TLE1,SS18SSX fusion gene was disclosed in the primary and recurrent tumor cells,it was therefore corrected as rhabdoid synovial sarcoma for the primary tumor.Conclusion Renal rhabdoid synovial sarcoma is rare.Renal primary rhabdoid synovial sarcoma is easily misdiagnosed as renal rhabdoid tumor.The renal rhabdoid synovial sarcoma has broadened the differential diagnosis of renal rhabdoid tumors spectrum.Even for a tumor with typical rhabdoid morphology,molecular biology method for differential diagnosis is needed.SS18-SSX fusion gene is the basis for diagnosis of synovial sarcoma.