A rare astrocytic tumor with rhabdoid features

We report an extremely rare tumor presenting with rhabdoid features in the left temporoparietal lobe near the trigone in an 18-year-old Japanese man. This tumor mainly consisted of medium to large round cells that proliferated diffusely and incoherently with a scant extracellular matrix. These tumor cells had an eccentric nucleus and an eosinophilic cytoplasm containing inclusion bodies and bundles of intermediate filaments. The nuclei of these cells were vesicular with prominent nucleoli. This tumor had an area appearing to be diffuse astrocytoma peripherally and lacked a primitive neuroectodermal tumor component, a mesenchymal component, and epithelial differentiation. INI expression, which is not observed in atypical teratoid/ rhabdoid tumor (AT/RT), was found in this tumor. From these findings, we concluded that this tumor was not AT/RT but an astrocytic tumor with rhabdoid features. We also concluded that the tumor cells exhibiting rhabdoid features had secondarily arisen from the peripheral area presenting an appearance of diffuse astrocytoma.     

Granulofilamentous meningioma

A 55-year old female was referred to the Department of Neurosurgery, Kitasato Hospital, because of a hearing impairment. Neuroimaging revealed a typical meningioma attached to the falx in the right frontal region. During surgery, an encapsulated, circumscribed, reddish-gray, slightly hard tumor attached to the falx was completely removed by an interhemispheric approach. On light microscopy, many of the tumor cells contained eosinophilic inclusions with single or multiple vacuoles that displaced the cytoplasm. The nuclei of the tumor cells were eccentric. There were no signs of malignancy in the specimen. Electron microscopy revealed that most of the eosinophilic inclusions were composed of filaments measuring 12 nm in diameter. There have been several reports of benign meningiomas with eosinophilic inclusions composed of intermediate filaments. The microscopic differences between these types of tumor and rhabdoid meningiomas are very subtle, and it is important the two types of tumors are not confused. Benign meningiomas with eosinophilic inclusions comprising intermediate filaments, for example the tumor described in this report, have been diagnosed as granulofilamentous meningiomas, which is a subtype of benign meningioma.     

Gastric adenocarcinoma with rhabdoid morphology

Extrarenal rhabdoid tumors (ERRTs) are very rare neoplasms and have been reported in a range of organs, including sixteen cases in the stomach. We describe a woman aged 86 years who had an advanced gastric tumor with lymph node metastasis. The tumor mostly showed a diffuse arrangement with a small glandular region. The tumor cells were non-cohesive and had polygonal morphology with eccentric vesicular nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm, i.e. they showed rhabdoid features. Immunohistochemically, the rhabdoid tumor cells were strongly positive for cytokeratins and vimentin. However, a candidate tumor suppressor gene of rhabdoid tumors, the INI1 gene, showed no mutations or loss of expression in the tumor cells. Although ERRTs typically have an aggressive clinical course, the patient was still alive without any evidence of recurrence or metastasis at 26 months after surgery. The rhabdoid features of the present case seemed to be a variant of gastric adenocarcinoma.     

Atypical teratoid/rhabdoid tumor of the brain: cytopathologic characteristics and differential diagnosis

BACKGROUND: Atypical teratoid/rhabdoid tumor (AT/RT) is a highly aggressive neoplasm with a unique cytogenetic profile. Although the clinicopathologic and radiologic features of AT/RT have been described previously, to the authors' knowledge the cytomorphologic profile of this tumor has not been studied well. METHODS: Nine samples of AT/RT from 8 patients were analyzed from the pathology files of 2 large institutions in a 10-year period (1993-2002). Material consisted of slides made from scraping and smearing (SS) or squash preparation (SP) of the tissue cores (six slides), fine-needle aspiration (FNA) (two slides), and cerebrospinal fluid (one slide). Smears were stained with Diff-Quik, Papanicolaou, and hematoxylin and eosin stains. RESULTS: There were 4 males and 4 females who ranged in age from 1-16 years (mean age, 7.1 years). Cytomorphologic features consisted of hypercellularity (eight of eight tumors); predominantly large tissue fragments with tumor cells surrounding proliferating capillaries depicting a "papillary-like" appearance (five of eight tumors); large, round, "plasmacytoid" cells and characteristic "rhabdoid" cells (i.e., intermediate-sized cells with granular to fibrillary, brightly eosinophilic cytoplasm with or without globoid "inclusions"; large, eccentrically located, round-to-reniform nuclei with single prominent nucleoli; eight of eight tumors); small, round, primitive "neuronal-appearing" cells with a high nuclear to cytoplasmic ratio (five of eight patients); and bizarre, multinucleated giant cells (two of eight tumors). Also seen were numerous apoptotic bodies, mitoses, and significant necrosis (seven of eight tumors), and prominent dystrophic calcification (four of eight tumors). CONCLUSIONS: AT/RT is extremely rare. Cytologic examination by SS, SP, or FNA offers a useful alternative to frozen section during intraoperative consultation. Cytomorphologic features are unique and lead to an accurate diagnosis in the right clinicoradiologic context. The differential diagnosis includes medulloblastoma (in cerebellar tumors), primitive neuroectodermal tumor (in suprasellar tumors), choroid plexus carcinoma, and malignant glioma.     

Deeply eosinophilic cell variant of signet-ring type of gastric carcinoma: a diagnostic dilemma

Signet-ring cell type of gastric carcinoma can easily escape detection by the pathologist, and this confusion is compounded by the presence of morphologic patterns other than the conventional appearance. One such morphologic variant is composed of deeply eosinophilic cells containing minute cytoplasmic granules with neutral mucin. With this morphology, epithelioid gastrointestinal stromal tumor (GIST), and hepatoid and rhabdoid variants of adenocarcinoma enter the list of diagnostic possibilities, and accurate diagnosis is essential for therapeutic and prognostic considerations. We report a 28-year-old man who presented with dyspepsia, nausea, vomiting, and black-colored stools. Endoscopy revealed a growth at the incisura, a biopsy specimen from which was reported as a poorly differentiated tumor. The patient underwent subtotal gastrectomy and the resected specimen showed a 6.5 × 4-cm circumferential growth in the antropyloric region. Histological sections from the growth showed transmural infiltration by deeply eosinophilic cells with hyperchromatic nuclei. A differential diagnosis of epithelioid GIST, rhabdoid variant, hepatoid variant, and signet-ring cell adenocarcinoma was considered. Special stains and immunohistochemistry confirmed the tumor to be a variant of signet-ring cell adenocarcinoma of the stomach. Morphologic variations of signet-ring cell carcinoma pose an important diagnostic dilemma, which has therapeutic and prognostic significance for the patient. These variants need to be recognized by pathologists to enable an accurate diagnosis.     

A step-wise logistic regression analysis of hepatocellular carcinoma. An aspiration biopsy study

Fine needle aspiration biopsy (FNAB) has become a popular method to diagnose mass lesions of the liver. Although several reports have listed FNAB criteria to be used to diagnose both primary and metastatic tumors of the liver, none have separated key cytologic criteria from secondary criteria. We reviewed the FNAB smears from 35 patients with proven hepatocellular carcinoma and 74 patients with proven metastatic tumors in the liver. All specimens were coded as to the presence or absence of the following variables: polygonal cells with centrally placed nuclei; well-defined, granular cytoplasm; large nucleoli; small cytoplasmic vacuoles; large cytoplasmic vacuoles; bile; polymorphonuclear leukocytes; malignant cells separated by sinusoidal vessels; endothelial cells surrounding tumor cell clusters; multinucleated tumor giant cells; basophilic intracytoplasmic inclusions; eosinophilic intracytoplasmic inclusions; and intranuclear cytoplasmic inclusions. A step-wise logistic regression analysis was performed on the data to determine the variables predictive of hepatocellular carcinoma. The statistical analysis selected polygonal cells with centrally placed nuclei, malignant cells separated by sinusoidal capillaries, and bile as the key cytologic criteria for hepatocellular carcinoma. Endothelial cells surrounding tumor cell clusters and intranuclear cytoplasmic inclusions were selected as secondary criteria by this analysis.     

肾脏及肾外横纹肌样瘤4 例报告并文献分析

目的:探讨横纹肌样瘤的临床病理特点、诊断及治疗。方法:收集天津医科大学肿瘤医院自2000年1 月至2014年9 月收治的4 例横纹肌样瘤患者的病例资料,结合文献进行回顾性分析。结果:4 例横纹肌样瘤患者中1 例原发于肾脏、其余3 例原发于肾外软组织。病理组织学上肿瘤细胞弥漫性生长,核仁突出,胞浆可见嗜酸性包涵体,核分裂多见。免疫组织化学显示波形蛋白（Vimentin）、上皮膜抗原（EMA）阳性,广谱角蛋白（CK）、CD99、CD34、S-100 均有不同程度阳性,人肌调节蛋白1（MyoD1）、结合蛋白（Desmin）、整合酶相互作用分子-1（INI- 1）阴性。结论:横纹肌样瘤是罕见且具有高度侵袭性的肿瘤,好发于肾脏,也可见于其他系统,其病理形态独特,需要结合免疫组织化学染色诊断。      

Rhabdoid glioblastoma in a child: case report and literature review

Rhabdoid glioblastoma is a rare type of glioblastoma characterized by cells resembling rhabdomyoblasts. Several reports have identified its aggressive clinical course and the pathological differences from other primary brain tumors. We report a case of rhabdoid glioblastoma in a 12-year-old boy who presented with headache and harbored a 70-mm solid tumor in the left temporal lobe. The tumor was surgically excised, but early tumor recurrence and leptomeningeal spread developed, and the patient died of the disease 4.9 months after surgery. Histologically, the tumor contained two distinct patterns of glioblastoma and rhabdoid cells with necrosis and hemorrhage. Immunohistochemical analysis revealed that both cells were positive for glial fibrillary acid protein, vimentin, and INI1, which is consistent with the reported diagnosis of rhabdoid glioblastoma. Genetic studies confirmed no loss of the INI1 gene and identified hemizygous deletion of the CDKN2A gene. We review reported cases of rhabdoid glioblastoma and summarize the clinical, radiological, and histological features.     

A complex karyotype in an atypical teratoid/rhabdoid tumor: case report and review of the literature

Atypical teratoid/rhabdoid tumor (AT/RT) is a highly aggressive and uncommon neoplasm of the central nervous system that usually occurs in children less than 2 years of age. It is characterized by deletions and/or mutations of the INI1 tumor suppressor gene located in chromosome band 22q11.2. We performed cytogenetic and molecular studies of an AT/RT on a 15-month-old boy. The tumor showed a complex karyotype with one cell line showing monosomy 22 and another near-tetraploid one with additional chromosomal abnormalities, involving chromosomes 2, 3, 5, 6, and Y, which had not been previously described. Sequence analysis of the tumor did not identify mutations of the INI1 gene. The karyotypic evolution observed in this tumor suggests that INI1 has an epigenetic role in the maintenance of genome integrity by affecting genes, which produces mitotic defects and polyploidy. Finally, this case is the first to support the theory that loss of INI1 could induce the chromosomal instability that might be responsible for the genesis of this tumor.     

肾恶性横纹肌样瘤临床病理分析及超微结构观察

目的:探讨肾恶性横纹肌样瘤(MRTK)的临床病理表现及超微结构特点。方法:用光镜、免疫组化及电镜等方法观察其病理组织学特点、免疫组化表达及超微结构。结果:光镜的典型特点是肿瘤细胞弥漫性排列,呈圆形、椭圆形及不规则形,胞质丰富,嗜酸性,部分胞质内可见透明状小体,细胞核圆形或椭圆形,核膜厚,核仁清楚,有的细胞核呈空泡状。部分核偏向一侧似浆细胞样。细胞内外见红染的包涵体。免疫组化显示肿瘤可表达多种抗原。电镜观察特异性表现是胞质内见中间丝及圆形不规则形纤维状或轮状小体。结论:肿瘤细胞弥漫排列呈浆细胞样,免疫组化多方向表达,可向神经性、上皮性、肌性等方向分化。电镜下胞质内中间丝及纤维轮状小体是特异性诊断标志。     

Extraskeletal myxoid chondrosarcoma in young children

Two extraskeletal myxoid chondrosarcomas with a solid soft tissue mass occurred on the right upper arm of a 4-year-old boy and on the chest wall of a 1-year-old boy. Microscopically, both tumors were characterized by lobular configuration and were sparsely cellular with a background of myxoid matrix. The cells were small and round, and appeared undifferentiated, sometimes with a narrow eosinophilic cytoplasm. They grew in nests or strands and sometimes in a single file. They were strongly positive for S-100 protein and vimentin. Ultrastructural features suggested that the cells had a poorly differentiated mesenchymal nature with chondrocytic differentiation. These are the sixth and seventh reported cases of extraskeletal myxoid chondrosarcoma occurring in children. There are definite differences between this tumor with immature features and the extraskeletal myxoid chondrosarcoma in adults. Problems of differential diagnoses from other small round cell sarcomas also are discussed.     

Establishment of a Human Small Cell Lung Carcinoma Cell Line Carrying Amplification of c-myc Gene and Chromosomal Translocation of t(3p;6p) and t(12q;17p)

A transplantable tumor and an in vitro culture cell line (GK-T3) were established from metastatic liver tissue of human small cell lung carcinoma (SCLC). Southern blot analysis revealed about 30-fold amplification of c- myc gene in the tumor cells in liver, xenografts, and in vitro cell line. The degree of c- myc amplification was essentially conserved through serial passages in nude mice and cultivation in vitro. The level of c- myc mRNA was significantly increased in these cells. Cytogenetically, numerical and complex structural abnormalities were observed in GK-T3 cells, including t(3p;6p), t(12q;17p), two homogeneously staining regions (hsrs) and several double minutes (dmins). These results suggest that activation of c- myc gene and alteration of gene(s) round these chromosomal breakpoints may play a role in tumorigenesis of GK-T3 SCLC.     

腹腔内促结缔组织增生性小圆细胞瘤临床病理分析

目的：探讨腹腔内促结缔组织增生性小圆细胞瘤临床病理特征。方法：对2例原发于腹腔的促结缔组织增生性小圆细胞瘤进行HE、免疫组织化学观察并复习相关文献。结果：肿瘤细胞为小圆形，呈巢团状排列，周围结缔组织及血管明显增生。免疫组织化学表达上皮性、间叶性、神经性标记物。结论：促结缔组织增生性小圆细胞瘤是一种特殊的高度恶性肿瘤；预后极差，主要应与小细胞未分化癌、尤文氏肉瘤、PNET、神经母细胞瘤等鉴别。     

Hepatoblastoma: cytomorphologic characteristics in serious cavity fluids

BACKGROUND: Hepatoblastoma (HBL) represents the most common primary hepatic tumor in children. Although the cytologic features of this tumor have been amply elucidated on fine-needle aspiration, exfoliative cytomorphologic characteristics have not been reported. The authors reviewed the cytopathologic features of six serous cavity fluids (SCF) from four patients with histologically proven HBL. METHODS: Five of the specimens evaluated were peritoneal fluids, and one specimen was pleural fluid from a patient with suspected pulmonary metastasis. Slides were prepared by cytocentrifugation and stained with Diff-Quik and Papanicolaou stains. The cytomorphologic features of each specimen were characterized, subclassified, and correlated histopathologically. RESULTS: All specimens showed hypercellular smears in a relatively clean background. Mixed embryonal and fetal subtypes of HBL disclosed three-dimensional clusters of neoplastic cells that formed straight or branched cords and acinus-like structures. The cells were moderately pleomorphic and had high nuclear-to-cytoplasmic (N/C) ratios. Occasional cells had eccentrically placed nuclei and vacuolated cytoplasm. Numerous mitotic figures were present. Rare intranuclear inclusions were noted. The anaplastic (small cell) subtype of HBL showed tight clusters of small, round, primitive cells with hyperchromatic nuclei, high N/C ratios, and prominent nuclear molding. In addition, there were numerous single cells with naked nuclei, often in an Indian-file configuration. Bile pigment, osteoid, and other mesenchymal components were absent in all specimens. CONCLUSIONS: The cytomorphologic features of HBL in SCF are quite characteristic. Although the differential diagnosis includes other childhood small, round, blue cell tumors and hepatocellular carcinoma, the above findings in the appropriate clinical-radiologic setting warrant a diagnosis of HBL.     

p53基因对人胃癌细胞生长及致瘤性的抑制作用

p53基因异常是人类肿瘤中最常见的基因变异之一．是最有希望用于肿瘤基因治疗的目的基因。在人胃癌组织中有较高频率的p53基因缺失和突变，为探讨p53基因用于胃癌治疗的可行性，我们采用脂质体介导方法将外源性野生型p53基因转染一株p53基因有部分缺失的人胃癌BGC823细胞，获得较高的转染效率，对转染后细胞DNA，RNA和蛋白进行分析．结果表明外源性p53基因已整合人细胞并获稳定表达，表达有外源性野生型p53基因的细胞生长速度，软琼脂集落形成率及裸鼠致瘤性均有部分抑制。这一结果进一步证明p53基因在胃癌发生发展过程中起重要作用．本研究为采用野生型p53基因转染进行胃癌基因治疗提供了细胞学实验依据。     

Primary PNET of kidney: report of two cases and review of literature

PNET of the kidney is a rare tumor with only a few published reports. In view of poorer prognosis and different therapeutic approach, renal PNET should therefore be differentiated from other primary renal neoplasma such as Wilms tumor, renal neuroblastoma and malignant rhabdoid tumor which on histology resemble renal PNET. Two cases of renal PNET have been described in this report. Cut surface of the tumor in both cases was greyish white lobulated, with multiple tiny cystic areas. Histologically, tumor consisted of loosely cohesive sheets of small to medium sized monomorphic cells with round nuclei and little cytoplasm. Tumor cells showed diffuse strong membrane positivity for MIC2 and focal weak to moderate positivity for NSE and vimentin. Renal PNET should therefore be included in differential diagnosis of rapidly enlarging renal lumps presenting with local infiltration and aggressive behaviour, particularly in children and young adults. Diffuse strong membrane positivity for MIC2 in PNET is helpful in differentiating it from other primary renal neoplasms.     

Biochemical and genetic characterization of the HBA71 Ewing's sarcoma cell surface antigen

Monoclonal antibody HBA71 detects a cell surface antigen of human Ewing's sarcomas and peripheral neuroepitheliomas that distinguishes these tumors from other small round cell tumors of childhood and adolescence. In the present study, we show that monoclonal antibody HBA71 reacts with polypeptides of Mr 32,000 and 30,000 and that the HBA71-coding gene segregates with human chromosomes X and Y in rodent-human hybrids. Therefore, we compared HBA71 to the T-cell leukemia antigen 12E7, which is encoded by the pseudoautosomal region of chromosomes X and Y. We show that monoclonal antibodies HBA71 and 12E7 (a) detect polypeptides of identical size, (b) react with mouse cells transfected with complementary DNA corresponding to the 12E7-coding gene, MIC2, and (c) give similar patterns of reactivity with human tumor cell lines and small round cell tumor tissues. Thus, HBA71 and 12E7 are identical or closely related antigens and the available MIC2 probes will facilitate analysis of the molecular mechanisms that determine differential HBA71 expression in small round cell tumors of childhood and adolescence.     

Establishment of a new human epithelioid sarcoma cell line, FU-EPS-1: molecular cytogenetic characterization by use of spectral karyotyping and comparative genomic hybridization

A small number of human epithelioid sarcoma cell lines have been reported, but their characterization at a molecular cytogenetic level is not well known. In this study, a new permanent human cell line, FU-EPS-1, derived from a metastatic epithelioid sarcoma developing in the axillary lymph node of a 21-year-old man is described. This cell line was characterized by use of immunocytochemistry, conventional G-banding analysis, spectral karyotyping (SKY) and comparative genomic hybridization (CGH). FU-EPS-1 cells were round, polygonal or spindle shaped with an abundant cytoplasm, and have been maintained continuously in vitro for over 100 passages during more than 15 months. Histologic features of the heterotransplanted tumors in severe combined immunodeficiency mice were essentially the same as those of the original tumor, revealing a multinodular proliferation of eosinophilic epithelioid and spindle cells. Both in vitro and in vivo, the cells were immunopositive for cytokeratins (AE1/AE3 and CAM5.2), epithelial membrane antigen, vimentin and CD34, but were negative for desmin, S-100 protein, CD31 or factor VIII-related antigen. By G-banding and SKY analyses, FU-EPS-1 revealed a hyperdiploid karyotype with the following chromosomal abnormalities: +i(5)(p10), -8, +13, der(13)t(8;13)(q?;p11), +der(19)t(9;19)(?;?) and del(22)(q13). In addition, CGH analysis identified gains of 5p, 9q, 19q and 22q and a loss of 8p. This study demonstrates the value of molecular cytogenetic techniques such as SKY and CGH in defining genomic alterations in greater detail. The FU-EPS-1 cell line will be exceedingly useful for biologic and molecular pathogenetic studies of human epithelioid sarcoma.     

Establishment of a Human Cell Line Secreting Neuron-specific Enolase from a Primitive Neuroectodermal Tumor of the Retroperitoneal Cavity

Primitive neuroectodermal tumor (PNET) is one of the small round cell malignancies of presumed neural crest origin for which an effective treatment has not yet been established. In the present study, a human cell line, designated KU-9, was established from a 27-year-old male patient with PNET of the retroperitoneal cavity and has been successfully maintained in nude mice and in culture. On histological examination, the primary tumor was composed of poorly differentiated small round cells arranged in clusters showing a variety of mitotic changes, and contained Homer-Wright rosettes. The histopathological appearance of the KU-9 xenografts was similar to that of the primary tumor. Electron microscopy revealed neurosecretory granules and cytoplasmic processes in the xenograft. No significant amplification of N- myc gene was observed in the KU-9 cells. The KU-9 cells showed chromosome numbers ranging from 56 to 61 with consistent structural abnormalities being add(2)(q31), +add(ll)(pll.2), +add(13)(pll.l), and + del(22)(q12). Cultured KU-9 cells grew exponentially with a doubling time of about 50 h and a time-dependent increase in medium levels of neuron-specific enolase (NSE) was noted. Serum levels of NSE in KU-9 tumor-bearing nude mice were significantly elevated and a linear relationship between the serum NSE levels and the tumor NSE content or tumor volume was observed, suggesting that serum levels of NSE may reflect the PNET tumor burden and tumor extent. These results indicate that the KU-9 cell line provides a reproducible model system which could be useful in gaining some insight into the histogenesis and oncogenesis of PNET and in establishing an effective treatment for PNET.