Primitive Cerebral Tumor with Rhabdoid Features: A Case of Phenotypic Rhabdoid Tumor of the Central Nervous System

The rhabdoid tumor (RT) was first described as an aggressive neoplasm of unknown histogenesis affecting the kidneys of infants and young children, but has since been reported in all ages and in many other primary sites, including the central nervous system. It has been shown, however, that the histologic and cytologic features of RT can be mimicked by many other tumors of known histogenesis. For this and other reasons it remains controversial whether cases of putative extrarenal RT represent the same histogenetic entity as RT of the kidney (RTK), another entity or entities, or merely a diverse collection of unrelated tumors sharing a common morphologic phenotype. The present paper describes a lethal primary cerebral tumor in a 26-month-old Hispanic boy that was composed predominantly of cells exhibiting the “classic” rhabdoid phenotype by light microscopy. lmmunocytochemical and ultrastructural studies disclosed features of primitive neuroglial differentiation not seen in RTK. The findings in this case, as well as evidence from other studies, would seem to support the notion that primary RT of the brain may in fact constitute a morphologic and clinicopathologic entity. However, hat entity likely represents a distinctive type of neuroglial neoplasm, more closely related t o other primitive brain tumors than t o RTK.     

Primitive Cerebral Tumor with Rhabdoid Features: A Case of Phenotypic Rhabdoid Tumor of the Central Nervous System

The rhabdoid tumor (RT) was first described as an aggressive neoplasm of unknown histogenesis affecting the kidneys of infants and young children, but has since been reported in all ages and in many other primary sites, including the central nervous system. It has been shown, however, that the histologic and cytologic features of RT can be mimicked by many other tumors of known histogenesis. For this and other reasons it remains controversial whether cases of putative extrarenal RT represent the same histogenetic entity as RT of the kidney (RTK), another entity or entities, or merely a diverse collection of unrelated tumors sharing a common morphologic phenotype. The present paper describes a lethal primary cerebral tumor in a 26-month-old Hispanic boy that was composed predominantly of cells exhibiting the “classic” rhabdoid phenotype by light microscopy. lmmunocytochemical and ultrastructural studies disclosed features of primitive neuroglial differentiation not seen in RTK. The findings in this case, as well as evidence from other studies, would seem to support the notion that primary RT of the brain may in fact constitute a morphologic and clinicopathologic entity. However, hat entity likely represents a distinctive type of neuroglial neoplasm, more closely related t o other primitive brain tumors than t o RTK.     

Pseudomesotheliomatous Adenocarcinoma of the Lung with Rhabdoid Features

Pseudomesotheliomatous adenocarcinoma of the lung is a rare entity, clinically and pathologically mimicking diffuse malignant pleural mesothelioma.

We report a case of pseudomesotheliomatous adenocarcinoma consisting of two distinct histopathologic components with marked differences in morphological appearance and immunohistochemical staining pattern: a small subpleural nodule consisting of adenocarcinoma and undifferentiated carcinoma with rhabdoid features, the latter extending to the visceral pleura in a diffuse mesothelioma-like growth pattern. The adenocarcinomatous component showed strong reactivity with various epithelial markers, but no reactivity with vimentin. The undifferentiated component showed strong reactivity for vimentin, but no reactivity for epithelial markers. Both components showed no reactivity with CEA, Ber Ep4, MOC-31, B72.3, cytokeratin 5/6, calretinin and thrombomodulin. Metastatic lesions in the duodenum and the periumbilical skin consisted entirely of undifferentiated carcinoma with rhabdoid features.

Fluorescence in situ hybridisation (FISH) was performed for chromosomes 4, 7, 20, and 22. FISH results showed polysomy 7 in both components. The diagnosis of pseudomesotheliomatous adenocarcinoma in this case was based on the finding of the subpleural nodule. We conclude that in cases of undifferentiated malignant pleural tumors with cells of rhabdoid phenotype, the possibility of peripheral pulmonary adenocarcinoma dedifferentiating into a more aggressive phenotype should be considered.     

Limitations of the Usefulness of Microvillous Ultrastructure in Distinguishing between Carcinoma Primary in and Metastatic to the Lung

We performed ultrastructural analysis on 70 consecutive patients with solitary cancers in lung with the following histologic classifications: adenocarcinoma (42 cases), bronchioloalveolar carcinoma (13), large cell carcinoma (4), and adenosquamous carcinoma (11). Of these 70 cases, nineteen (13 adenocarcinomas, 4 bronchioloalveolar carcinomas, and 2 adenosquamous carcinomas) contained cell surface microvilli with microvillous core rootlets and/or glycocalyceal bodies. Subsequent clinical followup revealed that three of these 19 cases were actually metastatic colon carcinoma. The remaining 16 patients are currently free of extrathoracic primary disease and are therefore, presumably, primary carcinoma of the lung. Since both primary and metastatic tumors showed cell surfaces with microvilli having core rootlets and glycocalyceal bodies, we conclude that the presence of these ultrastructural features does not always permit the distinction between primary and metastatic adenocarcinoma in lung.     

Gastrointestinal Stromal Tumor of the Stomach with Rhabdoid Phenotype: Immunohistochemical,Ultrastructural, and Immunoelectron Microscopic Evaluation

A variety of neoplasms with rhabdoid differentiation have been reported in many sites. The authors describe a case of gastrointestinal stromal tumor (GIST) of the stomach that exhibited prominent rhabdoid features. Immunohistochemically, the tumor cells displayed positive staining for vimentin, c-kit, CD34, and alpha smooth muscle actin. Ultrastructural examination of the rhabdoid tumor cells revealed paranuclear whorls of intermediate filaments, which were immunoreactive for vimentin by both light microscopic immunohistochemical and protein A gold immunoelectron microscopic techniques. On H&E light microscopic examination alone, such a tumor could be mistaken for a variety of epithelial, mesenchymal, or other neoplasms that may show rhabdoid features. One report of GIST with a rhabdoid histologic phenotype has been described. This is the second known report of such a case with immunophenotypic and ultrastructural evaluation, and the first case with immunoelectron microscopic examination.     

The Utility of Electron Microscopy in Cytopathology

Background: The use of ultrastructural analysis in the diagnostic work-up of histologic specimens has been well studied but less is known about the utility of electron microscopy (EM) in cytopathology. Design: 149,006 non-gynecologic cytology cases at the Massachusetts General Hospital between the years 1993 and 2006 were searched to identify those in which material had been submitted for EM. Cytologic and EM diagnoses were correlated with available histologic diagnoses. The results were put into one of three categories: confirmatory, diagnostic, or insufficient material for diagnosis (IMFD). Results: Material for EM was obtained from 178 cytology cases that included 131 fine-needle aspirates (FNA) and 47 exfoliative specimens. EM provided additional diagnostic information beyond that offered by cytologic examination alone in 32% of cases, and in 48% of cases EM confirmed the cytologic findings. Insufficient material and discrepant results were noted for EM evaluation in 19% of cases and in 1% cases respectively. EM was most useful when applied to FNAs for subclassifying tumors as epithelial or mesenchymal (45.6%), for the diagnosis of non-neoplastic processes (15.7%) such as alveolar proteinosis and amyloidosis, and for the identification of microorganisms (12.2%). In our study, although EM was infrequently applied to exfoliative specimens to distinguish mesothelioma from adenocarcinoma, it proved to be very useful in this setting. Conclusion: When adequate material is obtained, EM can contribute significantly to the evaluation of both FNA and exfoliative cytology cases, including the diagnosis and subclassification of epithelial and mesenchymal tumors, non-neoplastic processes, and the identification of microorganisms.     

Anaplastic Wilms' Tumor and Other Clinically Aggressive Childhood Renal Neoplasms: Ultrastructural and Immunocytochemical Features

The ultrastructural and immunocytochemical findings in a series of 32 rarely encountered childhood renal malignancies are reviewed. The discussion includes anaplastic Wilms' tumors, renal clear cell sarcomas, rhabdoid tumors, carcinomas, sarcomas, neuroendocrine tumors, and lymphomas. An attempt is made to assess the relative merits of these two techniques in the differential diagnosis of these often troublesome lesions.     

Cytogenetic Characteristics of a Malignant Rhabdoid Tumor Arising from the Paravertebral Region

The pathological and cytogenetic features of an extrarenal malignant rhabdoid tumor (MRT) arising from the paravertebral region in an infant were investigated. The patient died 4 months after diagnosis, due to aggressive tumor progression. The tumor was composed of medium-sized round cells with cytoplasm containing eosinophilic inclusions, which ultrastructurally were composed of densely packed whorled intermediate filaments. Flow-cytometric analysis of the tumor cells revealed a diploid pattern. Amplification of the N- myc oncogene was not identified. Immunohistologically, the inclusion bodies showed a positive reaction with antiserum against vimentin. The tumor cells were not reactive with antiserum against epithelial membrane antigen, anti-keratin (polyclonal) or cytokeratin (monoclonal, CK1), but did react with 5H10, an antiserum established from human sarcomatous Wilms'tumor. This case is discussed with reference to the literature on extrarenal MRT, placing stress on the histogenesis of this tumor.     

A Case of Malignant Rhabdoid Tumor Arising from Soft Parts in the Prepubic Region

An extrarenal malignant rhabdoid tumor arising from soft parts in the prepubic region of a 37 year-old man is described. This case appears to be unusual with regard to its location and age at onset. To our knowledge, the patient is the oldest recorded in whom such a lesion has arisen. Histologically, the tumor consisted of an admixture of polygonal and elongated cells with abundant eosinophilic cytoplasm frequently containing hyaline-like globules. Ultrastructurally, these cytoplasmic inclusions were compatible with intermediate filaments. Immunohisto-chemical staining disclosed keratin (non squamous epithelial type) and epithelial membrane antigen positivity. These characteristic features were identical to malignant rhabdoid tumor of the kidney seen in infants and young children. This extrarenal malignant rhabdoid tumor showed an aggressive clinical course, although its exact histogenesis was unclear. Acta Pathol Jpn 39: 677 682, 1989.     

血清NSE、CA242、TPA、CEA联检对肺癌的诊断价值

目的:探讨血清神经元特异性烯醇化酶(NSE) 、糖类抗原CA242、组织多肽抗原(TPA) 、癌胚抗原(CEA)联检对肺癌的诊断价值.方法:应用酶联免疫法(ELISA)对102例肺癌、33例肺结核及30名健康人血清进行观察.结果:①四项指标在不同组织类型肺癌中均有不同程度升高且明显高于肺结核组及健康对照组.②综合评价肺癌组两项同时阳性者腺癌(AC)为75%、鳞癌(Sq)50%及小细胞肺癌(SCLC) 65%,而结核组假阳性率仅为9%,健康组未发现假阳性者.③NSE诊断SCLC的敏感性为72%,特异性为97%;CA242诊断AC的敏感性为62%、Sq39%及SCLC为31%,特异性为90%.结论:四项指标对不同组织类型肺癌均有一定诊断价值,联合测定时可以提高对肺癌的阳性诊断.     

Epithelioid Hemangioendothelioma of the Lung

Light and electron microscopic features of an epithelioid hemangioendothelioma of the lung in a 43-year-old woman are reported. The tumor cells stained for factor VIII-related antigen. A mass excised from the thigh 10 years earlier showed identical appearances.     

Primary epithelioid malignant schwannoma of the lung

This is the first documented report of a case of primary malignant nerve sheath tumor of the lung showing an epithelioid malignant schwannoma. A 55 year old Japanese female underwent lobectomy of the middle lobe of the right lung because of a large, rounded tumorous shadow found on chest X-ray film. Light microscopic examination of the neoplasm disclosed an epithelioid malignant schwannoma with foci having a spindle-cell sarcomatous pattern. The neoplastic cells were positive for S-100 protein and neuron specific enolase by the immunoperoxidase method. Transmission electron microscopy showed basement membrane-like material surrounding the neoplastic cells and long spacing collagens in the interstitial spaces. The patient died of a recurrent tumor in the right hemithorax 5 months after undergoing lobectomy. An autopsy revealed no primary site of the neoplasm outside the lung. Furthermore, there was no evidence of neurofibromatosis.     

Meningioma of Lung: First Report with Light and Electron Microscopic Findings

This is the first report of a primary meningioma of the lung. The lesion was present at least 4 years prior to its operative removal. The 59-year-old patient is still healthy 2-1/2 years after operation. All examinations, including computed tomography, failed to detect another primary tumor. Light and electron microscopic findings are identical to those in endotheliomatous meningioma. The relations to the so-called minute pulmonary chemodectomas and the probable histogenesis are discussed.     

Meningioma of Lung: First Report with Light and Electron Microscopic Findings

This is the first report of a primary meningioma of the lung. The lesion was present at least 4 years prior to its operative removal. The 59-year-old patient is still healthy 2–1/2 years after operation. All examinations, including computed tomography, failed to detect another primary tumor. Light and electron microscopic findings are identical to those in endotheliomatous meningioma. The relations to the so-called minute pulmonary chemodectomas and the probable histogenesis are discussed.     

Factors Affecting the Outcomes of Patients with Malignant Rhabdoid Tumors: A Population-Based Study

Objective: Malignant rhabdoid tumor (MRT) is a rare but aggressive malignancy. It has been a long time since data on this tumor have been updated.Methods: We retrospectively reviewed patients from the SEER database who were pathologically diagnosed with MRT and analyzed incidence rates, clinical features and survival using Stata 12.0.Results: In total, 544 patients were included in the epidemiological analysis. There were two peak periods of MRT incidence: patients younger than 4 years and those older than 70 years. Further survival analysis showed that the survival of children (especially younger than 1 year) was markedly worse than that of adults (P<0.01), and different primary sites were associated with different age groups and survival outcomes. The central nervous system (CNS) was the most common primary site (50.00%), followed by the kidney (15.66%). Patients with MRTs that originated from the digestive system experienced worse survival outcomes than those with MRTs originating from other locations. Primary site surgery conferred survival benefits to patients with renal and digestive system MRTs (HR = 0.06, CI: 0.02-0.23, P<0.01; HR=0.10, CI: 0.02-0.48, P<0.01), whereas radiotherapy conferred benefits to patients with CNS, bone and soft tissue MRTs (HR=0.22, CI: 0.15-0.34, P<0.01; HR=0.44, CI: 0.21-0.90 P=0.03).Conclusions: Our results indicate that age and the primary site of MRT are critical clinical factors that affect patient survival and treatment choices. Primary site tumor resection should be considered for renal and digestive system MRTs, and systematic therapy, including surgery and radiotherapy, should be recommended for the treatment of CNS, bone and soft tissue MRTs.     

Comparative Ultrastructure of Needle Aspiration Biopsy and Surgical Resection Specimens of Lung Tumors

Ultrastructural examination affords conclusive evidence for classification of lung tumors. Tissue properly fixed for electron microscopy is not available in many cases, however. Ultrastructural diagnosis of resected specimens obviously follows, rather than directs, the surgical treatment. Fine-needle aspiration (FNA) of lung masses is recommended as a means to obtain lung tumor tissue for electron microscopy. Nevertheless, no comparison has been made between ultrastructural information gained from aspiration specimens and resected specimens. Electron microscopy was performed on transthoracic FNA specimens of 10 lung tumors for which surgical resection was subsequently performed. Glutaraldehyde-fixed specimens from FNA and surgical resection were prepared for electron microscopy according to routine procedures. Fixation of the FNA specimens was equivalent or superior to that of the resected specimens in 9 of the cases. Three of the FNA specimens contained necrotic as well as viable tissue. Features essential for diagnosis such as desmosomes, junctions, neurosecretory granules, intermediate filaments, glycogen, lipid, mucin, and microvilli were identifiable in both FNA and resected specimens. FNA specimens therefore yield a representative sample of the ultra-structural features of lung tumors when adequate cellular material is obtained. Use of a coaxial needle sampling technique with immediate microscopic assessment reduces the likelihood of retrieving only blood or necrotic tissue in the electron microscopy specimens.