Laparoscopic Excision of a Uterine Adenomatoid Tumor and a Coexisting Ovarian Teratoma: A Case Report and Literature Review.

Adenomatoid tumors (ATs) are rare, benign neoplasms occurring mainly in reproductive organs such as the uterus, ovaries, fallopian tubes, and testes. Uterine adenomatoid tumors (UATs) are generally incidentally diagnosed during histopathological examination of excisional biopsies performed for other indications, most commonly uterine leiomyomas. We herein present a 38-year-old woman who underwent laparoscopic excision of a uterine leiomyoma and a right ovarian teratoma. Microscopic examination of the excisional biopsy revealed that the enucleated uterine tumor was composed of proliferating glandular tissue covered with single-layered cells that were surrounded by proliferating smooth muscle cells, corresponding exactly to the features of UATs. The excised ovarian cyst was confirmed to be a typical mature cystic teratoma. According to these histopathological findings, the patient was finally diagnosed with a UAT and coexisting teratoma. No recurrence was detected up to 6 months after excision. To the best of our knowledge, this is the eighth case report on laparoscopically enucleated UATs. Although recurrence risk may be low in UATs, further case reports are necessary to elucidate the safety and validity of laparoscopic excision for UATs.

Oligodendroglial cell proliferation arising in an ovarian mature cystic teratoma. Clinicopathological, inmunohistochemical, and ultrastructural study of a case that may represent an oligodendroglioma.

Ovarian mature cystic teratoma (OMCT) is an ovarian benign neoplasm with excellent prognosis presenting components of the three germinal layers. However, transformation into a malignant neoplasm is a rare event (so-called somatic transformation). In most of the cases, the malignant component expresses as epidermoid carcinoma, but occasionally central nervous system tumors occur. Some of the previously reported tumors are astrocytoma, glioblastoma, and ependymoma. Somatic transformation of OMCT into an oligodendroglioma is exceptional. We report a 19-year-old female with a left OMCT with an area of oligonedroglial cells proliferation characterized by immunohistochemical studies with positivity for GFAP and S100, with a low Ki67 index (5%). Additionally, electron microscopy revealed oligodendrocytes with parallel bundles of cytoplasmic intermediate filaments, confirming the oligodendroglial nature of the proliferation. The patient was treated only with left oophorectomy, and three and half years after surgery, there is no evidence of disease.

Fetus in fetu versus teratoma fetiforme / Foetus in foetu versus foetiform teratoma

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[Structure of teeth in mature ovarian teratoma].

MATERIAL AND METHODS: The authors investigated three mature ovarian dermoid cysts that were found to contain atypically developed teeth (one tooth in one cyst; 2 teeth in another cyst, and a set of 8 teeth with jawbone fragments in the third one). Their structure was examined using the epoxy resin plastination technique to obtain plastinated sections. RESULTS: Some of these teratomous teeth have obvious signs of alteration in both dentin and enamel, which may be referred to as fluorosis or macular enamel hypoplasia in one case whereas other sections indicate a caries lesion. CONCLUSION: These facts are contradictory to the concept of the exogenous nature of dental caries, which is accepted in dentistry.

Atypical teratoid/rhabdoid tumor arising in pleomorphic xanthoastrocytoma: a case report.

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare, highly malignant, true rhabdoid tumor in the central nervous system predominantly presenting in young children.AT/RT typically shows rhabdoid cells which can also be seen in other tumors, but it is differentiated from other tumors by the specific genetic alteration involving the SMARCB1 gene. Only a few cases of AT/RT arising in low-grade glioma have been reported. A 13-year-old girl presented with headache, dizziness, nausea and vomiting.A 4.7 cm cerebellar mass was found on MRI.The mass was totally removed. Histologically, the tumor revealed two distinct morphologic appearances: central areas of AT/RT containing rhabdoid cells and sarcomatous component in the background of pleomorphic xanthoastrocytoma(PXA). Immunohistochemically, PXA areas retained nuclear expression of INI-1 and low Ki-67 proliferation index, whereas AT/RT component showed loss of INI-1 nuclear expression and markedly elevated Ki-67 proliferation index. Epithelial membrane antigen (EMA), smooth muscle actin (SMA), and p53 protein were positive only in AT/RT. BRAF V600E mutation was identified in PXA by real-time polymerase chain reaction.We report a rare case of AT/RT arising in PXA which is supposed to progress by inactivation of INI-1 in a pre-existing PXA.

Characterization of ultrastructure and collagen composition of the teratoma membrane: comparison to the amniotic membrane.

The structural and morphological properties of the teratoma membrane were investigated to better understand the pathogenesis of ovarian teratomas. A mature cystic teratoma and amnion were obtained from patients who underwent laparoscopic cystectomy and uncomplicated delivery, respectively. The teratoma membrane was divided into three layers according to the results of the histological analysis. Each layer showed distinct morphological properties, including an outer layer that was uniformly arranged, a middle layer with an irregular pattern of fibers, and an inner layer that was structurally dense with a wavy pattern of fibers. The morphology of the layers of the amniotic membrane was the reverse that of the teratoma membrane. In the teratoma membrane, the outer layer was primarily composed of type III collagen and the inner layer had a large amount of type III and IV collagen. The amniotic membrane showed a small amount of type III collagen in the outer layer, whereas the inner layer had large amounts of type I, III, and IV collagen. In the teratoma membrane, the collagen fibrils were arranged regularly in the outer layer, but irregularly in the inner layer. In the amniotic membrane, the arrangement of collagen fibrils was the reverse that of the teratoma membrane. Additionally, the collagen fibrils in the teratoma membrane were thinner than those of the amniotic membrane and had slightly shorter d-spacing. Two membranes showed the differences in collagen fibril arrangement, which may caused by the different functional roles.

The fetal larynx and pharynx: structure and development on two- and three-dimensional ultrasound.

OBJECTIVES: To present a systematic approach for evaluating the fetal pharynx and larynx based on two- and three-dimensional ultrasound (2D-US and 3D-US) modalities, describing the sonographic appearance and function of the fetal upper respiratory tract and measuring the anatomical components of the pharynx and larynx. METHODS: Gravidae presenting from the late first trimester to mid-gestation for routine booked examinations with structurally normal singleton fetuses of confirmed gestational age were enrolled. Transabdominal 2D-US was performed for anatomical and functional evaluation of the pharynx and larynx. Color Doppler was used to show fluid motion in the target area. 3D-US (Voluson® E6 with RAB-4-8-D transducer) scans of the fetal neck were acquired during fetal quiescence and in the absence of movements of the pharynx and larynx. Multiplanar reconstruction (MPR) in post-processing allowed adjustment of the volume to obtain the coronal plane. After a learning period to understand the sonographic anatomy of the target area, we measured the pharynx width and height, the upper, middle and lower larynx width and the larynx height. Render mode was applied for spatial evaluation of the target area. We developed a new methodological approach for structured evaluation of the fetal pharynx and larynx based on five spatial planes: posterior and anterior coronal planes and high, mid and low axial planes. RESULTS: We examined 582 fetuses during the second trimester of pregnancy; target anatomy was imaged successfully in 218 patients at 11-24 gestational weeks. Acquisition added approximately 1 min to examination time. Rates of successful visualization and measurements increased significantly as pregnancy progressed, being 23% (46/194) at 11-13 weeks, 29% (69/240) at 14-16 weeks, 35% (18/51) at 17-19 weeks and 88% (85/97) at 20-24 weeks (P < 0.01). Pharynx components identified were: the sphenoid bone, pterygoid processes, constrictor muscles, piriform recesses and uvula. Larynx components identified were: the epiglottis, aryepiglottic folds, corniculate cartilages, arytenoid cartilages, cricoid cartilage, thyroid cartilage and vocal cords. MPR showed the biconcave shape of the uvula, which may explain the 'equals sign' observed on 2D-US. We observed the bilateral mode of movements of the constrictor muscles, aryepiglottic folds and vocal cords, and the bidirectional fluid jet flows through the larynx. Scatterplots of measured structures vs gestational age were created. Pharynx width ranged from 0.11 to 0.93 (mean ± SD, 0.48 ± 0.17) cm; pharynx height ranged from 0.23 to 2.01 (mean ± SD, 0.94 ± 0.34) cm; upper larynx width ranged from 0.04 to 0.37 (mean ± SD, 0.15 ± 0.07) cm; middle larynx width ranged from 0.08 to 0.77 (mean ± SD, 0.34 ± 0.16) cm; lower larynx width ranged from 0.05 to 0.64 (mean ± SD, 0.24 ± 0.11) cm; and larynx height ranged from 0.20 to 1.83 (mean ± SD, 0.71 ± 0.31) cm. All measurements were positively correlated with gestational age. CONCLUSIONS: The fetal larynx and pharynx can be evaluated thoroughly using 2D- and 3D-US modalities. Knowledge of normal anatomy, function and biometry may prove useful in the evaluation of anatomical or functional pathology involving the fetal upper respiratory tract. Recognition of anatomical anomalies may enhance fetal intervention such as balloon placement in cases of diaphragmatic hernia.

Intracoelomic teratoma in a domestic duck (Anas platyrhynchos domesticus): a case report including immunohistochemistry and electron microscopy.

A female domestic duck (Anas platyrhynchos domesticus) suddenly died with abdominal distension and a large multilobulated mass within the coelomic cavity was found. Histologically and immunohistochemically, a benign mature tridermic teratoma was diagnosed and epithelial structures, cartilage, bone, myxoid tissue, adipocytes, muscle cells, cystic spaces lined by squamous epithelium, feather follicles, melanocytes and variable neural and glial differentiation were recognized. By electron microscopy, desmosomes, keratin bundles, dense core neurosecretory granules, aberrant Z-line material and Luse bodies were found. To our knowledge, this is the first report of tridermic benign intracoelomic teratoma of a duck in which an extensive immunohistochemical and electron microscopic examination has been performed and in which a common neural and glial differentiation has been demonstrated.

Ultrastructural evidence of ependymal differentiation in a genetically proven atypical teratoid/rhabdoid tumor.

INTRODUCTION: We describe a case of genetically proven atypical teratoid/rhabdoid tumor (ATRT), showing ultrastructural evidence of ependymal differentiation. Such differentiation has not been reported so far in ATRT. CONCLUSION: This finding supports the concept that ATRTs as the majority of central nervous system embryonal tumors may derive from an immature and pluripotent neuroectodermal cell capable of differentiating along multiple lineages.

An immunohistochemical and electron microscopic study of atypical teratoid/rhabdoid tumor.

We report two infant cases with atypical teratoid/rhabdoid tumor (AT/RT) located in the cerebellar vermis and spinal cord. MRI showed the tumors were isointense on T1-weighted images and mixed intensity of isointense and slight high intensity on T2-weighted images. Postcontrast MRI demonstrated clear margin of tumor and heterogeneous strong enhancement. It was difficult to differentiate the tumor from medulloblastoma by hematoxylin and eosin staining. However, immunohistochemical staining showed that these tumor cells react positively for cytokeratin, smooth muscle actin (SMA), and epithelial membrane antigen (EMA) and helped us with the differentiation. Electron microscopic study has confirmed the presence of mesenchymal components, such as filaments and desmosome junctions in the rhabdoid cells, but no neuronal components. The tumors rapidly increased in size, showing high MIB-1 index, and the prognosis was gave.

[Cystic teratoma of the pancreas].

A case of pancreatic cystic teratoma is described in a 52-year-old woman. The tumor is macroscopically presented by an 8 x 8 x 7-cm multifocal cyst. Histological, immunohistochemical, and electron microscopic studies have revealed the derivatives of three germinal layers (ecto-, endo, and mesoderma).

¿Cuál es su diagnóstico? / What is your diagnosis?

Varón de 25 años que consulta por presentar aumentodel tamaño del testículo izquierdo. En la palpación, senota una masa nodular, de bordes bien definidos, en lamitad inferior de la gónada. En el examen ecográfi cose confirma la presencia de esta masa. El paciente essometido a orquiectomía...

The road from teratocarcinoma to human embryonic stem cells.

In this article, a brief review of the research that began with the study of murine teratomas of the testis and ultimately led to the culture of human embryonic stem cells is discussed. Most of the space will be devoted to the studies in which the author personally took part, and the discussion will also touch upon some of the crucial experiments important for the understanding of this entire research effort.

Tetraploid embryonic stem cells contribute to the inner cell mass of mouse blastocysts.

The demonstration that mouse somatic cells can be reprogrammed following fusion with embryonic stem (ES) cells may provide an alternative to somatic cell nuclear transfer (therapeutic cloning) to generate autologous stem cells. In an attempt to produce cells with an increased pool of reprogramming factors, tetraploid ES cells were produced by polyethylene glycol mediated fusion of two ES cell lines transfected with plasmids carrying puromycin or neomycin resistance cassettes, respectively, followed by double antibiotic selection. Tetraploid ES cells retain properties characteristic of diploid ES cells, including the expression of pluripotent gene markers Oct4 and Rex1. On injection into the testis capsule of severe combined immunodeficient (SCID) mice, tetraploid ES cells are able to form teratomas containing cells representative of all three germ layers. Further, these cells demonstrated the ability to integrate into the inner cell mass of blastocysts. This study indicates that tetraploid ES cells are promising candidates as cytoplasm donors for reprogramming studies.

Nuclear cloning of embryonal carcinoma cells.

Embryonal carcinoma (EC) cells have served as a model to study the relationship between cancer and cellular differentiation given their potential to produce tumors and, to varying degrees, participate in embryonic development. Here, nuclear transplantation was used to assess the extent to which the tumorigenic and developmental potential of EC cells is governed by epigenetic as opposed to genetic alterations. Nuclei from three independent mouse EC cell lines (F9, P19, and METT-1) with differing developmental and tumorigenic potentials all were able to direct early embryo development, producing morphologically normal blastocysts that gave rise to nuclear transfer (NT)-derived embryonic stem (ES) cell lines at a high efficiency. However, when tested for tumor or chimera formation, the resulting NT ES cells displayed an identical potential as their respective donor EC cells, in stark contrast to previously reported NT ES cells derived from transfer of untransformed cells. Consistent with this finding, comparative genomic hybridization identified previously undescribed genetic lesions in the EC cell lines. Therefore, nonreprogrammable genetic modifications within EC nuclei define the developmental and tumorigenic potential of resulting NT ES cells. Our findings support the notion that cancer results from the deregulation of stem cells and further suggest that the genetics of ECs will reveal genes involved in stem cell self-renewal and pluripotency.

Spontaneous thyroid-containing teratoma associated with impaired development in the African clawed frog, Xenopus laevis.

Teratomas are rare in amphibians and the neoplasm described here, which had a significant thyroid carcinoma component, is the first tumour of this type to be reported in Xenopus laevis. The thyroid component contained moderately to well-differentiated acinar glands showing much hyperplasia, dysplasia, and reduced and distorted colloid reservoirs. Cartilaginous, neural, muscular, mesenchymal and gut-like epithelial components were also observed in this ventral mediastinal neoplasm, indicating aberrant proliferation from all three germ layers. This teratoma was only one abnormality in a complex of developmental changes, followed for 28 months, which appeared in a single generation of sibling 2-week-old Xenopus larvae. Two hundred larvae produced by an apparently normal adult pair initially showed ocular defects, including microphthalmia, anophthalmia and tumours projecting near the eyes. During further development up to 28 months, mediastinal tumours developed in nine frogs; these tumours were associated with reduced growth, the frogs reaching only 13-20% of normal weight, and greatly enhanced ventral pigmentation.