Cytomorphological features of atypical teratoid/rhabdoid tumor: An account of 12 years' experience

Atypical teratoid rhabdoid tumor (AT/RT), an aggressive neoplasm mostly affecting young children, is characterized by rhabdoid cells together with epithelial, mesenchymal and primitive differentiation. Diagnosing AT/RT in intraoperative consultation and cerebrospinal fluid (CSF) samples may therefore pose problems. Fourteen immunohistochemically proven AT/RTs diagnosed between 2000 and 2012 were collected. Material consisted of squash smears prepared during intraoperative consultation (thirteen) and CSF smears (three). MGG‐stained CSF smears and H&E stained squash smears were reviewed by a neuropathologist and a cytopathologist. The intraoperative diagnoses were based on squash preparations and 3 out of 13 were consistent with AT/RT, 4 were considered medulloblastoma/primitive neuroectodermal tumors (PNET), 3 were deferred to paraffin section for tumor typing, and another 3 were misdiagnosed as ependymoma, germinoma and malignant glioma. Morphological assessment of intraoperative squash preparations showed that AT/RTs can have a mixture of pseudopapillary and diffuse smearing patterns. Cytomorphologic features consisted of characteristic rhabdoid cells (8/9); primitive appearing cells with a high nuclear to cytoplasmic ratio (7/9); bi‐/multinucleated cells (3/9); rare necrosis/apoptosis and mitoses. Three CSF smears showed high cellularity and inclusion‐bearing large cells. These cells are characterized by reniform/oval, eccentrically placed nuclei with cytoplasmic perinuclear light stained areas which are not seen in intraoperative squash preparations. Differential diagnosis of AT/RT in cytology involves medulloblastoma/PNET, ependymoma, glioma and germinoma among all others. Overlapping features of AT/RT with entities in differential diagnosis are discussed with a special emphasis of rhabdoid cells being the strongest feature to aid in reaching the diagnosis of AT/RT. Diagn. Cytopathol. 2014;42:856–862. © 2014 Wiley Periodicals, Inc.     

Atypical teratoid/rhabdoid tumor: analysis of cytomorphologic features in CSF, focused on the differential diagnosis from mimickers

Atypical teratoid and rhabdoid tumor (AT/RT) is a rare tumor with fatal clinical consequences, usually affecting young children. A significant portion of patients present with dissemination to cerebrobspinal fluid (CSF). However, a limited number of studies are available regarding the cytomorphologic findings of AT/RT in CSF. We collected eight cases of CSF cytology of AT/RT and describe the cytomorphologic features of AT/RT in CSF. Typical rhabdoid cells are found in most cases and they are characterized by eccentric nuclei, abundant cytoplasm, and clustering of the tumor cells. The presence of these cells in CSF indicates disseminated diseases and aggressive therapeutic consideration for patient management is required.     

中枢神经系统非典型畸胎瘤样/横纹肌样瘤10例临床病理分析

目的 探讨中枢神经系统非典型畸胎瘤样/横纹肌样瘤(atypical teratoid/rhabdoid tumor,AT/RT)的临床病理学特征、诊断、鉴别诊断及预后.方法 回顾性分析2016年～2019年中南大学湘雅医院诊治的10例AT/RT的临床、影像学及病理学特征,并对其进行随访及相关文献复习.结果 10例患者发...     

Claudin-6 is of limited sensitivity and specificity for the diagnosis of atypical teratoid/rhabdoid tumors

Recent gene expression microarray analyses have indicated that claudin-6 is specifically expressed in atypical teratoid rhabdoid tumors (AT/RTs), suggesting a role as a positive diagnostic marker in addition to SMARCB1 (INI1) loss, which is encountered in the majority of AT/RTs. In order to investigate the potential of claudin-6 as a diagnostic marker, expression was investigated in 59 AT/RTs and 60 other primary central nervous system (CNS) tumors, including primitive neuroectodermal tumors, medulloblastomas, choroid plexus tumors, and both pediatric and adult low- and high-grade gliomas using immunohistochemistry. Claudin-6 was expressed in 17/59 AT/RTs (29%), but also in a variety of other primary CNS tumors, including 60% of medulloblastomas and 21% of malignant gliomas. Even though high staining scores (2+ or 3+) were more often encountered in AT/RTs (Chi-square 4.177; P=0.041), the overall frequency of claudin-6 staining was not significantly higher in AT/RTs as compared with the other tumors (17/59 vs. 16/60; Chi-square=0.328; P=0.567). In a subgroup of 43 AT/RT patients, of which follow-up data were available, claudin-6 expression did not show any correlation with survival. In conclusion, claudin-6 immunohistochemistry is of limited sensitivity and specificity for the diagnosis of AT/RT and does not correlate with clinical behavior.     

中枢神经系统非典型畸胎瘤样/横纹肌样瘤临床病理特点

目的探讨中枢神经系统非典型畸胎瘤样／横纹肌样瘤(atypical teratoid／rhabdoid tumor，AT／RT)的临床病理特征、组织发生及预后。方法应用光镜、特殊染色及免疫组化染色观察1例2岁儿童大脑AT／RT的病理组织学特点，结合国内外文献进行讨论。结果肿瘤含有横纹肌样细胞、原始神经外胚层、上皮及间叶多向分化成分。肿瘤中网状纤维丰．富。免疫组化染色Vim、EMA、CKpan、GFAP、Syn及CgA均呈阳性表达，PLAP、CD117、SMA及：NF?呈阴性反应。结论AT／RT为发生在儿童中枢神经系统罕见的高度恶性肿瘤，多数患者1年内死亡。肿瘤极易误诊为髓母细胞瘤、原始神经外胚叶肿瘤(PNET)、脉络丛乳头状癌及生殖细胞肿瘤。免疫组化染色对确诊AT／RT十分重要。本瘤的组织发生仍不清楚。     

Adult variant of atypical teratoid/rhabdoid tumor: Immunohistochemical and ultrastructural confirmation of a rare tumor in the sella tursica

Atypical teratoid/rhabdoid tumor (AT/RT) is a distinctive neoplasm of young children characterized by diverse histology and fatal course. Adult presentation is rare. We describe the diagnostic problems associated with an AT/RT arising in the sellar region in a 46-year-old female.     

Atypical teratoid/rhabdoid tumor in a patient with Beckwith-Wiedemann syndrome

Beckwith-Wiedemann syndrome (BWS) is a genetic disorder associated with an increased risk of childhood tumors. Here we describe a patient with BWS who developed a central nervous system atypical teratoid/rhabdoid tumor (AT/RT). To our knowledge, despite the known cancer predisposition, this patient is the first described with BWS to develop an AT/RT. Due to the high propensity of these patients to develop childhood tumors, in addition to routine diagnostic tests, analysis of the tumor DNA using the Illumina Infinium whole-genome genotyping 550K Beadchip was performed to investigate a possible common underlying mechanism for his BWS and AT/RT. The only alteration detected was monosomy 22, which was accompanied by a somatic mutation in the INI1 rhabdoid tumor gene. These results suggest that, despite an underlying cancer predisposition, the occurrence of BWS and AT/RT in this patient may be unrelated.     

Primary atypical teratoid/rhabdoid tumor of central nervous system in children: a clinicopathological analysis and review of literature in China

Atypical teratoid/rhabdoid tumor (AT/RT) is a very rare and highly malignant embryonal tumor in the central nervous system (CNS). Five patients (4 girls and 1 boy) with AT/RT were treated in our hospital. The clinical histories, symptoms, neuroimaging aspects, therapies, histological and immunohistochemical findings and follow-up information were reviewed. The patients ranged from 8 to 40 months with a mean age of 20.6 months. One tumor was located in the spinal cord, two in cerebellum and two in the pineal region. The imagings of the tumors resemble medulloblastomas. Pathological examinations showed that one patient had medulloblastoma differentiation, one had choroid plexus carcinoma differentiation, and one had mesenchymal components. Immunohistochemical staining showed that all of the tumors lost the nuclear expression of integrase interactor 1 (INI1), and were positive for Vimentin, S-100 protein and epithelial membrane antigen. One case with no recurrence after 24 months may have benefited from radical excision and postoperative radiotherapy. The other 4 patients died 8, 4, 1 and 1-month respectively after operation without radiotherapy. The diagnosis of AT/RT depends on full sampling, careful observation the morphological characteristics and INI1 examination, even when the tumor are presented in uncommon sites, such as the spinal cord and the pineal region.     

松果体区不典型畸胎样/横纹肌样肿瘤一例

患儿男,29个月。因精神萎靡半月余,呕吐2 d来吉林大学第一医院就诊。磁共振成像显示松果体区异常信号影,脑积水。患者入院第4天行神经电生理监测显微镜下肿瘤切除术,出院随访4个月,患者死亡。病理检查：镜下见肿瘤细胞弥漫性生长,部分区域可见坏死,细胞核空泡状、核仁明显,个别胞质内可见嗜酸性小体,免疫组织化学肿瘤细胞细胞角蛋...     

Renal and extrarenal congenital rhabdoid tumor: diagnosis by fine-needle aspiration biopsy and FISH

We report on 2 patients with congenital malignant rhabdoid tumor, one located to the kidney and the other to the soft parts of the cheek. Initial diagnosis was performed through percutaneous fine-needle aspiration biopsies, which yielded cytologic smears exhibiting highly characteristic rhabdoid cells, i.e., cells with a large, vesicular nucleus with a prominent nucleolus and cytoplasm exhibiting a large, dense, paranuclear inclusion. Interphase FISH demonstrated only one signal (heterozygous deletion) for the BCR gene in both cases, supporting the diagnosis. Surgical pathology and immunohistochemistry of both cases confirmed the diagnosis. Both patients died within the following 6 mo to 1 yr.     

Malignant rhabdoid tumor of the vulva: Case report with cytological, immunohistochemical, ultrastructural and DNA ploidy studies and a review of the literature

A case of malignant rhabdoid tumor of the vulva in a 25-year-old female was examined. The patient presented with a subcutaneous nodule in the lefl labium majus. Smears of the material obtained by percutaneus fineneedle asplratlon demonstrated clusters of atypical cells with prominent nucleoli. The tumor measured 6 × 5 × 5 cm and appeared tan to brown on the cut surface and partly cystlc. Pathological findings obtalned from intraoperative frozen tlssue sections had been originally interpreted as rhabdomyosar-coma. Light microscopic examination revealed that polyge nal tumor cells having vesicular nuclei with prominent nucleoli were arranged in sheets and the great majority of the tumor cells contained an eosinophillc globular paranu-clear cytoplasmic Inclusion. Ultrastructurally, this cytoplas-mic inclusion corresponds to whirls of intermediate filaments. Vlmentln immunoreactlvity was detected in both the cytoplasm and cytoplamic inclusion of almost all the tumor cells. No cytokeratin and desmin immunoreactivlty were detected In the tumor cells. The Ki-67 labeling index was 36% and the DNA content of the tumor cells, which was examined by image cytometry, demonstrated diploidy (DNA Index = 0.95).     

Fine-needle aspiration biopsy diagnosis of extrarenal malignant rhabdoid tumor

Two cases of extrarenal malignant rhabdoid tumors are presented in which diagnosis was suggested by fine-needle aspiration biopsy and confirmed by histologic and electron microscopic examination. Fine-needle aspiration smears in both cases revealed round to polygonal cells with vesicular nuclei and prominent nucleoli. Several tumor cells contained cytoplasmic inclusions composed of intermediate filaments. A majority of the tumor cells stained strongly for vimentin and cytokeratin. Electron microscopic examination revealed many cells with large aggregates of intermediate filaments corresponding to the cytoplasmic inclusions. Fine-needle aspiration biopsy may be used for diagnosing malignant rhabdoid tumor. The diagnosis may be further confirmed by immunohistochemistry and electron microscopy. Diagn Cytopathol 1994;11:271–276. © 1994 Wiley-Liss, Inc.     

Paratesticular congenital malignant rhabdoid tumor diagnosed by fine-needle aspiration cytology. a case report

We report the FNA features of a congenital malignant extrarenal rhabdoid tumor (MERT) located in the right paratesticular area of a newborn full-term boy (39 wk gestation), with disseminated metastases in the liver and right parietal region. The diagnosis was suggested two days after birth by fine-needle aspiration biopsy (FNAB) of the parietal mass, which demonstrated an atypical large cell proliferation with vesicular nuclei, prominent nucleoli, and abundant cytoplasm exhibiting paranuclear dense inclusions. The diagnosis was confirmed by histopathologic and immunohistochemical examination of the primary paratesticular tumor. To the best of our knowledge, this is the third MERT reported in the paratesticular region, one of the few congenital extrarenal non-central nervous system cases, and the third congenital case (renal or extrarenal) primarily diagnosed by FNAB. We emphasize the characteristic cytologic features of a congenital rhabdoid tumor, which must be known by pathologists because of the clinical and prognostic implications. Diagn. Cytopathol. 2004;30:46-50.     

Extrarenal primitive malignant tumor with rhabdoid features: fine-needle aspiration cytology, immunocytochemistry, and electron microscopy of a case

We describe a malignant pelvic tumor with rhabdoid-like features that arose in the sacroiliac region of a 15-year-old girl. Fine-needle aspiration (FNA) cytology showed large cells with glassy cytoplasm, globular hyaline cytoplasmic inclusions, and prominent nucleoli. Immunocytochemical methods applied to FNA material revealed immunoreactivity for cytokeratin, epithelial membrane antigen, and vimentin; the cells failed to react with antibodies to desmin. This distinct appearance and phenotype was most consistent with a diagnosis of extrarenal malignant rhabdoid tumor. Electron microscopy confirmed this interpretation, showing whorled filamentous aggregates in the cytoplasm of the tumor cells.     

Fine-needle aspiration cytology of recurrent granulosa cell tumor: case report with differential diagnosis and immunocytochemistry

We report a case of an adult-type granulosa cell tumor of the ovary which was diagnosed in a 20-yr-old woman. After a 21-yr disease-free interval, she developed a pelvic recurrence, followed by a splenic metastasis and, more recently, omental masses. This report is concerned with the fine-needle aspiration (FNA) diagnosis of the granulosa cell tumor in the latter site and corroboration of the interpretation by immunocytochemistry. Only one previous case is similar to the present one documenting the role of immunocytochemistry in the evaluation of suspected metastatic granulosa cell tumor. The cytopathologic features of metastatic granular cell tumor have been described in a limited number of previous reports.     

Malignant rhabdoid tumor of the prostatic region

Summary We describe a malignant rhabdoid tumour of the prostatic region in a 14-year old boy. The tumour showed positive immunoreactivity for epidermal prekeratin, monoclonal cytokeratin, epithelial membrane antigen, carcinoembryonic antigen and monoclonal vimentin but was negative for myoglobin, alfa-fetoprotein and lysozyme. Electron microscopy revealed pleomorphic cells with collections of paranuclear intermediate filaments, sheaves of tonofilaments and abundant microvilli in some tumour cells. Epithelial derivation was also suggested by occasional intracytoplasmic lumina and rare cell junctions.     

Atypical teratoid rhabdoid tumors (ATRTs): the British Columbia's Children's Hospital's experience, 1986-2006

As "atypical teratoid rhabdoid tumors" (ATRTs) may mimic "small round blue cell tumors" (SRBCT), we reexamined our ATRT experience focusing upon INI-1 immunohistochemistry (IHC). All high-grade pediatric brain tumors occurring from 1986-2006 at our institution underwent INI-1 IHC. Clinicopathologic data from each INI-1 immunonegative case were reviewed. Additional genetic, epigenetic and IHC analyses (including interrogation of INI-1 and CLDN6) were performed on a subset of the INI-1 immunonegative cases. Twelve INI-1 IHC negative tumors were identified retrospectively, of which only two previously carried the diagnosis of ATRT. Overall, the clinicopathologic and genetic data supported the assertion that all 12 cases represented ATRT. Unexpectedly, three long-term survivors (4.2, 7.0 and 8.5 years) were identified. As hypothesized, "teratoid" and "rhabdoid" histologic features were relatively infrequent despite gross total resections in some cases. Methylation specific polymer chain reaction (PCR) (MSP) revealed a uniform methylation pattern across all cases and gene promoters tested (ie, MGMT, HIC1, MLH3 and RASSF1); notably, all cases demonstrated unmethylated MGMT promoters. Our data demonstate that a primitive non-rhabdoid histophenotype is common among ATRTs and highlights the diagnostic importance of INI-1 IHC. Epigenetically, the MGMT promoter is usually unmethylated in ATRT, suggesting that potential temozolomide-based chemotherapy may be of limited efficacy.