Pediatric SMARCB1/INI1-deficient poorly differentiated chordoma of the skull base: report of five cases and review of literature / 中华病理学杂志

Objective: To investigate the clinicopathological characteristics and differential diagnosis of pediatric SMARCB1/INI1-deficient poorly differentiated chordoma (PDC) of the skull base. Methods: Five cases of SMARCB1/INI1-deficient PDC were identified in 139 cases of chordoma diagnosed in Sanbo Brain Institute, Capital Medical University, Beijing, China from March 2017 to March 2021. The clinical and imaging data of the 5 PDCs were collected. H&E and immunohistochemical staining, and DNA methylation array were used, and the relevant literatures were reviewed. Results: All 5 PDCs were located at the clivus. The average age of the patients was 6.4 years, ranging from 3 to 16 years. Three patients were female and two were male. Morphologically, in contrast with classical chordomas, they presented as epithelioid or spindle tumor cells organized in sheets or nests, with necrosis, active mitoses, and infiltration into surrounding tissue. All cases showed positivity of CKpan, EMA, vimentin and brachyury (nuclear stain), and loss of nuclear SMARCB1/INI1 expression. S-100 protein expression was not frequent (2/5). Ki-67 proliferative index was high (20%-50%). All cases had over-expressed p53. It was necessary to differentiate SMARCB1/INI1-dificient PDC from SMARCB1/INI1-dificient tumors occurring at skull base of children or the tumors with epithelial and spindle cell morphological features. The 3 PDCs with DNA methylation testing showed the methylation profiles different from the pediatric atypical teratoid/rhabdoid tumors. They formed an independent methylation profile cluster. The clinical prognosis of the 5 patients was poor, and the overall survival time was 2-17 months. Conclusions: PDC is a special subtype of chordoma, which often affects children and occurs in the clivus. The PDC shares epithelioid or spindle cell morphologic features which are different from the classic chordoma. Besides the typical immunohistochemical profile of chordoma, PDC also has loss of nuclear SMARCB1/INI1 expression and distinct epigenetic characteristics.

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)

Tumor rabdoide teratoide en paciente pediátrico: reporte de caso / Teratoid rhabdoid tumor in pediatric patient: case report

El tumor Rabdoide/Teratoide atípico (AT/RT) representa un subtipo tumoral primario de sistema nervioso central bastante raro, con un alto grado de malignidad y de pobre pronóstico (grado IV según OMS) encontrándose principalmente en niños menores de 3 años sin antecedentes de importancia y con cuadros clínicos bastante insidiosos que representa un reto en cuanto al diagnóstico y tratamiento teniendo en cuenta la limitada cantidad de casos reportados a nivel mundial, así como poca literatura disponible. Presentamos el caso de una paciente femenina de 23 meses de edad quien ingresa al servicio de urgencias del Hospital Militar Central (Bogotá, Colombia) en coma con midriasis izquierda, deshidratación grado 2, con escanografía cerebral simple de ingreso donde se observa lesión ligeramente isodensa fronto parieto occipital izquierda con sangrado intralesional que ejerce importante efecto de masa desplazando la línea media 22 mm y produce herniación del uncus, paraclínicos que reportan anemia, trombocitopenia y tiempos de coagulación prolongados, por lo cual se decide ingresar a salas de cirugía como urgencia vital realizando resección de lesión macroscópica de aspecto grisáceo, muy vascularizada, similar al tejido cerebral con sangrado fácil y muy difícil de controlar. 72 horas después requiere nueva intervención quirúrgica por inestabilidad hemodinámica durante el postoperatorio encontrando lesión de similares características, se envían muestras a patología reportando diagnóstico patológico definitivo: tumor Teratoide Rabdoide atípico grado IV OMS.

Atypical teratoid rhabdoid tumor (AT/RT) represents a subtype of malignant CNS neoplasms quite rare, with a high degree of malignancy and poor prognosis (WHO grade IV) found mainly in children younger than 3 years old without medical history of diseases and with Clinical characteristics quite insidious that represents a challenge in the diagnosis and treatment taking into account the limited number of cases reported, as well as little literature available. We report a 23 months of age female who is admitted to the emergency room of the Central Military Hospital (Bogotá, Colombia) in coma with mydriasis, dehydration, In the cranial scan showed injury slightly isodensa fronto-parieto-occipital left with intralesional bleeding that exerts important mass effect by moving the Midline of the brain 22 mm and produces herniation of the uncus, paraclinical reported anemia, thrombocytopenia and prolonged coagulation times, by which it decides to enter rooms for surgery making resection of macroscopic lesion of grayish look, highly vascularized, similar to the brain tissue with easy bleeding and very difficult to control. 72 hours after requires new surgical intervention for hemodynamic instability during the postoperative period finding similar lesion characteristics, samples are sent to Pathology reporting final pathological diagnosis: tumor atypical Teratoid Rhabdoid WHO grade IV by OMS.

Atypical Teratoid Rhabdoid Tumor in a Child: Case Report / Tumor teratóide rabdóide atípico emuma criança: relato de caso

Atypical teratoid/rhabdoid tumor (ATRT) is a rare and aggressive type of embryonal tumor of the central nervous system (CNS) occurring in childhood. The present study aims to describe the case of a 16-year-old girl who presented with an occipital mass lesion that was diagnosed as ATRT.We present a brief review of the current knowledge of the treatment of this rare neoplasm. A previously healthy 16-year-old girl was referred after two episodes of partial complex seizure 2 weeks before admission. MRI showed a right parieto-occipital lesion with homogeneous contrast-enhancing and significant surrounding brain edema. The patient underwent uneventful surgical resection of the lesion and was discharged home on the fifth postoperative day. Pathologic examination revealed it to be ATRT. The patient was referred to chemotherapy and radiotherapy. After 6 months of follow-up, the patient remains free of seizure and disease progression. ATRT is a rare and aggressive disease. Therefore, early diagnosis and treatment may improve the patient's prognosis and quality of life.

O tumor teratoide rabdoide atípico (TTRA) é um tipo de neoplasia rara, com comportamento maligno, que atinge o sistema nervoso central (SNC) de crianças. O objetivo do presente estudo é relatar o caso de uma paciente de 16 anos de idade admitida no nosso serviço com uma lesão occipital que revelou tratar-se de TTRA em estudo anatomopatológico. Uma paciente previamente hígida foi admitida no nosso serviço referindo ocorrência de dois episódios de crises convulsivas nas últimas 2 semanas. A ressonância magnética de crânio mostrou a presença de lesão occipital direita com captação homogênea do meio de contraste. A paciente foi submetida a cirurgia de ressecção da lesão expansiva sem intercorrências. A análise histopatológica e imuno-histoquímica revelou tratar-se de TTRA. A paciente foi encaminhada para a realização de quimioterapia e radioterapia complementares ao tratamento cirúrgico. Após 6 meses de seguimento ambulatorial, a paciente encontra-se assintomática, sem recorrência das crises convulsivas e/ou progressão radiológica da doença. TTRA é uma doença rara e agressiva. Com isso, diagnóstico e tratamento antecipados podem aprimorar prognóstico e qualidade de vida dos pacientes.

Tumor maligno rabdoide primitivo de maxilar inferior / Primitive malignant rhabdoid tumor of the mandible

El término tumor rabdoide fue utilizado en un comienzo para neoplasias renales con inclusiones citoplasmáticashialinas, que corresponden ultraestructuralmente a filamentos intermedios. Inicialmente descrito en 1978 como una variante rabdosarcomatoide del tumor de Wilms, separándose tres años después por presentar diferencias clinicopatológicas.Después de la descripción clinicohistológica del tumor rabdoide a nivel renal se han descrito tumoresmorfológicamente idénticos en tejidos blandos y órganos. La cavidad oral no es la excepción y han aparecido informes de carcinoma escamocelular con fenotipos rabdoides orales documentados en el año 1996.Se informa este caso debido a su rareza y su origen primario en el maxilar inferior.

Unusual radiological characteristics of teratoid/rhabdoid brain tumor in children

We report a case of atypical teratoid rhabdoid brain tumor is a 4 months old male child, who presented with unusual radiological findings, that can be confused with other brain tumors, so we high light these unusual imaging features to aid in making correct diagnosis

Atypical teratoid/rhabdoid tumor mimicking tuberculous meningitis.

Atypical teratoid/rhabdoid tumor of the central nervous system is a highly malignant neoplasm in infants and young children. We report a 6 year-old girl with atypical teratoid/rhabdoid tumor. Based on cerebrospinal fluid examination MRI scan and family history of tuberculosis; we diagnosed tuberculous meningitis. There was inadequate response to the antituberculosis therapy; so we performed stereotactic brain biopsy. Pathologic result revealed high grade atypical teratoid/rhabdoid tumor.

Intraventricular rhabdoid tumor.

Malignant rhabdoid tumor (MRT) most commonly occurs in kidney. In the central nervous system, cerebellum is the most common site of occurrence. CNS rhabdoid tumors typically occur in small children, do not respond favorably to treatment and are usually fatal within 1-year. Here is reported a 4-year-old child who presented with features of raised intracranial pressure. Apart from papillodema, there were no neurological signs. Imaging revealed a left lateral ventricular heterogeneous mass abutting the foramen of monro, with mild irregular contrast enhancement and hydrocephalus. The child underwent right ventriculo-peritoneal shunt followed by craniotomy and gross total tumor resection. He was discharged 10-days after surgery without any neurological deficits. Histopathology revealed features compatible with rhabdoid tumor. Despite radiotherapy and chemotherapy, the child died of progressive disease 10-months after surgery. The highly malignant nature of this tumor makes early diagnosis essential for aggressive management and prognostication.

Primary Intracranial Atypical Teratoid/Rhabdoid Tumor in a Child: A Case Report

Rhabdoid tumors of the central nervous system are rare malignancies. Primary central nervous system atypical teratoid/rhabdoid tumors (ATT/RhTs) mostly occur during early childhood and are almost invariably fatal. These tumors show similar histological and radiological features to primitive neuroectodermal tumor-medulloblastoma (PNET-MB) but have different biological behaviors. We report a case of primary intracranial ATT/RhT in the posterior cranial fossa of a child. Preoperative radiological diagnosis was PNET-MB, but pathological diagnosis is ATT/ RhT. The case involved a 16-month-old baby boy who presented with severe headache, vomiting, and gait disturbance. He was treated by surgical resection, chemotherapy, and radiotherapy. Despite aggressive therapy, he died 19 months after diagnosis. Clinical, radiological, and histopathological features of primary intracranial ATT/RhT are discussed with a special emphasis on the differential diagnosis from PNET-MB.

Primary malignant rhabdoid tumor of the brain: CT and MR findings

PURPOSE: To describe the CT and MR findings of primary malignant rhabdoid tumor (MRT) of the brain, which is a rare but very aggressive neoplasm in childhood. MATERIALS AND METHODS: Retrospectively, we evaluated the CT and MR findings of 5 patients of primary MRT of the brain with a review of clinical records. RESULTS: The primary MRTs of the brain were large (n = 4) with a tendency to be associated with necrosis, hemorrhage (n = 2) and calcification (n = 2). Solid components of the tumor showed increased attenuation on precontrast CT scan and iso- or slightly hyper-signal intensity on T2-weighted images probably due to hypercellularity. Solid components of the tumor were also well enhanced on contrast-enhanced CT scan (n = 5) and MRI (n = 2). In 1 case with intratumoral bleeding, MR findings were variable on T1-weighted and T2-weighted images. Intracranial and intraspinal metastasis were found in 2 cases on preoperative MR studies. Follow-up CT and MR studies showed recurrence of the tumor and/or leptomeningeal metastasis in 3 cases. CONCLUSIONS: Although CT and MR findings of primary MRT of the brain are nonspecific, a tendency toward large size, calcification and intratumoral bleeding may be attributed to CT and MR findings. The solid components of tumors could present hyperdense on precontrast CT scan and iso- or slightly hyper-signal intensity on T2-weighted MR image. Preoperative and follow-up MR studies are important to detect metastatic foci.

Tumor rabdoide-teratoide primario del sistema nervioso central de comportamiento benigno. Informe de un caso / Primary rabdoid-teratoid tumor of the central nervous system with benign behavior. Report of one case

Se presenta el caso de un tumor frontoparietal derecho de una adolescente de 13 años de edad, con características hostológicas e inmunohistoquímicas de tumor rabdoideoteratoide (TR), de localización frontoparietal derecha y con evolución neurológica durante 4 años, manifestada únicamente por monoparesia braquial izquierda de -1 hasta hoy. El tumor primario de S.N.C. es patológicamente idéntico al tumor rabdoide maligno de riñón, tiene el comportamiento clinicopatológico de un sarcoma de alta malignidad y en los niños (edad de mayor presentación) se caracteriza por su gran agresividad a corto plazo, con recurrencia frecuente, y progresión rápida a la muerte, independientemente del tratamiento instituido. Nosostros reportamos un caso, que se ha comportado como una neoplasia benigna, expresada fenotípicamente como tumor rabdoide extrarrenal

Tumor rabdoide cerebral primario: informe de un caso y revisión de la literatura / Rhabdoid tumor originating in the brain. Report of a case and review of the literature

Se presenta el caso de un niño de 12 años con un tumor rabdoide primario del encéfalo, intra y extra-axial, con evolución de seis meses. El tumor rodeaba e infiltraba nervios ópticos, quiasma, circunvoluciones rectas y orbitarias, e hipotálamo. Se hizo resección parcial de la neoplasia y en el posoperatorio hubo manifestaciones graves de disfunción hipotalámica. En la autopsia se encontró diseminación subaracnoidea extensa. Se revisan los conceptos actuales acerca del tumor rabdoide renal, extrarrenal y del sistema nervioso central, con énfasis en la histogénesis y los criterios de diagnóstico