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At least 145 records · Page 8Linked to original sources
PubMed2005

A 10-month-old boy with a large pineal tumor.

February 2005. Case report of a 10-month-old boy with a large tumor located in the pineal gland, consisting of glia, ganglion cells, pigmented neuroepithelium and striated muscle, without immature components. The combination of neuroectodermal and mesenchymal constituents includes entities as pineal anlage tumor (melanotic neuroectodermal tumor of infancy, MNTI), ectomesenchymoma, medullomyoblastoma, and teratoma in the differential diagnosis. Lack of immature elements in this case, however, eliminates ectomesenchymoma and medullomyoblastoma from the differential diagnosis. Retinal anlage tumors, to be considered as MNTI at the site of the pineal gland, usually harbor immature components as well. Therefore, the present case does not match strict criteria of any of the categories mentioned and therefore we have designated it as a "pineal anlage tumor (without immature components)".

Diagnosis, Differential↗
PubMed2000

Miscellaneous rare paratesticular tumors.

A few uncommon but distinctive tumors may preferentially involve the paratestis. The 3 unusual tumors that represent the focus of this discussion are the ovarian-type epithelial tumors (OTET), the desmoplastic small round cell tumor (DSRCT), and the melanotic neuroectodermal tumor of infancy (MNTI). The OTETs are testicular homologues of their more common namesake counterparts that arise in the ovary. Most frequent of these are serous tumors of borderline malignancy, with fewer cases of serous carcinomas or other forms of mullerian differentiation. DSRCT is an increasingly recognized, aggressive, "small blue cell" neoplasm with distinctive clinical and pathologic features. These polyphenotypic tumors characteristically, but not invariably, arise in intimate association with the serosal membrane of the peritoneal cavity and harbor a signature translocation-t(11;22)(p13,q12). In the paratestis they often involve the surface of the epididymis. The MNTI is an enigmatic, histologically distinctive, low-grade neoplasm occasionally encountered in the epididymis. Recognition of its features is essential to avoid misdiagnosis as a more aggressive "small blue cell" neoplasm and consequent therapeutic mismanagement. Primary hematopoietic tumors of the paratesticular structures are rare. There appears to be a tendency for young men to have low-grade lymphomas with an indolent course and older patients to develop higher-grade tumors. Plasmacytoma and granulocytic sarcoma of the paratestis are even more rare and are often susceptible to misinterpretation. Finally, metastatic tumors and a variety of other very rare neoplasms are discussed.

Adolescent↗
PubMed1998

[Melanotic progonoma. Apropos of a voluminous tumor in an infant].

We report the case of a voluminous melanotic neuroectodermic tumor, also termed melanotic progonoma, which developed in a 5 month old infant, recalling the main aspects of such uncommon non-odontogenic tumors with characteristic histological features. The large size of the tumor can hinder feeding in infants. Surgical cure is generally easy and outcome quite satisfactory without recurrence.

Connective Tissue↗
PubMedDate not supplied

Usefulness of electron microscopy in the diagnosis of "small" round cell tumors of the sinonasal region.

The sinonasal region is known to harbor several types of tumors that belong to the general category of "small" round cell tumors and offer considerable diagnostic challenges. This study evaluated 33 cases of such tumors by electron microscopy to characterize their ultrastructural features in conjunction with immunohistochemistry, in an attempt to define diagnostic criteria of various types. Electron microscopy was useful in the proper classification of tumors in 27 cases: esthesioneuroblastoma (EN), 12; undifferentiated carcinoma, 6; melanoma, 3; lymphoma, 3; melanotic neuroectodermal tumor, 1; rhabdomyosarcoma, 1; and pituitary adenoma, 1. In the remaining six cases, the ultrastructural features were those of poorly differentiated carcinomas. They usually exhibited some epithelial characteristics as well as neuroendocrine features by immunohistochemistry and electron microscopy. These tumors could be best described as poorly differentiated neuro-endocrine carcinomas (malignant neuroepitheliomas). The most controversial diagnostic problems existed between the tumors categorized as esthesioneuroblastomas and neuroendocrine (NE) carcinomas. Esthesioneuroblastomas were characterized by uniform round nucleated cells with variable amounts of dendritic processes containing numerous dense core granules ranging from 150 to 350 nm in the perikarya and dendritic processes. Dendritic processes contained longitudinally arranged neural tubules and revealed an occasional synaptic junction. In three of the 12 cases of EN, cells with the appearance of sustentacular cells were recognized by electron microscopy. The NE carcinomas usually consisted of closely packed round cells with scanty cytoplasm that lacked any feature of neuroblastic cells. The tumor cells in this category often were epithelioid in appearance and exhibited a varying degree of cytokeratin positivity. Neuron-specific enolase was also positive in all cases, further suggesting their neuroepithelial nature. The greatest difference between EN and NE carcinomas was the absence of sustentacular cells in NE carcinomas. Immunohistochemical and electron microscopic studies are essential in the differential diagnosis of EN and NE carcinomas, because their microscopic appearance is very similar. The study indicates that EM is useful in the diagnostic categorization of sinonasal tumors of uncertain nature, particularly when it is used in conjunction with immunohistochemistry.

Carcinoma↗
PubMed1986

Melanotic neuroectodermal neurocranial tumor of infancy of extra-intra-and subdural right temporal location: CT examination, surgical treatment, literature review.

A melanotic neuroectodermal neurocranial tumor of infancy of extra-intra-subdural right temporal location, examined by CT and successfully operated in a 33-month-old boy is reported in context with the literature. Out of 30 cases (including our case) of melanotic neuroectodermal neurocranial and intracranial tumors (MNNIT) 18 were located in the neurocranium (MNNT) and 12 intracranially, i.e. in the brain and cerebellum (MNIT). 23 tumors were located medially (11 at the anterior fontanel, one at the posterior fontanel, one in the 3rd ventricle, one in the sella turcica, one in the pineal region, 8 in the cerebellar vermis) and 7 laterally (five involved the temporal bone, one of which with intracranial propagation (our case), one in the temporal lobe of the brain, one in the skull posterior to the mastoid process). Twenty-eight cases were children (16 boys, 8 girls, four not stated), two adults. The location is important in respect to biology and surgery: MNNIT can be grouped as to its relation to the arachnoid barrier layer into malignant and benign. MNIT localised medially subarachnoidally are malignant. MNNT of small dimensions localised medially and laterally extraarachnoidally are benign. MNNT of extreme dimensions localised medially extra-intradurally are also benign, but difficult to treat. In the MNNT when diagnosed early and operated radically, the mortality can be lowered. Our case, presented on CT (1978) as first case of combined extra-intra-subdural location, represents the 173rd MNT and the 18th related to neurocranium.

Brain Neoplasms↗
PubMed2005

[Autologous rib graft for restoration of continuity defects of the mandible].

BACKGROUND: Reconstruction of mandibular defects following tumor resection in infants is a particular challenge. Although autologous rib grafts have no relevance nowadays for restoration of mandibular bone defects following ablative tumor surgery due to limited bone stock and the availability of other donor areas, they are a useful surgical alternative following tumor surgery in infants. PATIENTS AND METHOD: We here report on the 5- and 10-year follow-up of two children who were diagnosed with benign tumors of the mandible with osseous destruction at the age of 4 and 6 months, respectively. Histological diagnoses were melanotic neuroectodermal tumor and hemangioendothelioma of the mandible. Following continuity resection of the mandible lateral mandibular bone defects were restored using autologous rib grafts. Yearly clinical and radiological follow-up visits in both children were performed to assess growth of the facial skeleton as well as mandibular growth. RESULT: Cephalometric measurements on panorex films as well as 3D CT scans revealed slight vertical growth excess and transversal growth inhibition of the reconstructed mandible in comparison with the non-operated side. DISCUSSION: Although further growth of rib grafts is difficult to predict and occlusal disharmony may occur due to physiologic maxillary growth and growth of the unaffected mandible, we believe that autologous rib grafts can be ideally used for restoration of mandibular continuity defects in newborns. Clinical follow-up visits on a yearly basis and orthodontic controls are useful for early orthodontic treatment of growth deficits. Further corrective surgery with bone augmentation or osseous distraction is required following completion of growth of the facial skeleton.

Bone Transplantation↗
PubMed2006

Long-term results after mandibular continuity resection in infancy: the role of autogenous rib grafts for mandibular restoration.

Reconstruction of mandibular defects after tumor resection in infants is a particular challenge. Although autogenous rib grafts have no relevance nowadays for restoration of mandibular bone defects after ablative tumor surgery because of limited bone stock and the availability of other donor areas, they are a useful surgical alternative after tumor surgery in infants. We here report on a 6-month, 5-year, and 10-year follow-up of three children who were diagnosed with benign tumors of the mandible with osseous destruction at the ages of 4 months, 6 months, and 2 years, respectively. Histologic diagnoses were melanotic neuroectodermal tumor, hemangioendothelioma of the mandible, and ameloblastoma. After continuity resection of the mandible, latero-mandibular bone defects were restored using autogenous rib grafts. Both clinical and radiologic follow-up visits in all children were performed to assess growth of the facial skeleton as well as the mandibular growth. Cephalometric measurements on Panorex films and three-dimensional computed tomographic scans revealed slight vertical growth excess and transversal growth inhibition of the reconstructed mandible in comparison with the nonoperated side. Although further growth of rib grafts is difficult to predict and occlusal disharmony may occur because of physiologic maxillary growth and growth of the unaffected mandible, we think that autogenous rib grafts can be ideally used for restoration of mandibular continuity defects in newborns and young children. Clinical follow-up visits on a yearly basis and orthodontic controls are useful for early orthodontic treatment of growth deficits. Further corrective surgery with bone augmentation or osseous distraction is required after completion of growth of the facial skeleton.

Ameloblastoma↗
PubMed1983

[Melanotic ectodermal tumor of infancy (melanotic progonoma)--an unusual soft tissue tumor].

In rare cases an utmost uncommonly pigmented lesion is found in young infants which is mostly located in the anterior maxilla. The histogenesis of this unusual soft tissue tumor has provoked a long-lasting debate, which is reflected in many synonyms. There is no anatomical precursor and the possibility of a phylogenetic ancestral form is discussed. Therefore, the term melanotic progonoma was proposed. Because of the derivation from neural crest cells the designation melanotic neuroectodermal tumor of infancy was introduced. This name is now generally accepted. In this study, two typical cases of this rare tumor are described. The tumors are composed of large epithelial-like melanin-producing cells and small nonpigmented cells, so-called lymphocyte- like cells resembling neuroblasts. The diagnostic relevant histological pattern is characterized by intensely pigmented cells arranged either in strands or clusters often forming the lining of small cleft-like or tubular spaces, or by alveolar structures surrounded by a fibrovascular stromal component. At ultrastructural level, the pigment corresponds to the cutaneous type of neural crest type of melanin. The histogenesis of these lesions and the classification of pigmented benign and malignant neuroectodermal tumors of the soft tissues are discussed especially taking into consideration the concept of the soft tissue variant of melanomas. The melanotic neuroectodermal tumor of infancy is a benign growth Only in very few cases a fatal outcome is reported in the literature. The melanotic neuroectodermal tumor of infancy must be distinguished from other types of benign and malignant neuroectodermal tumors. From histological point of view and with regard to its biological behaviour this lesion is a particular entity of pigmented neuroectodermal tumors of the soft tissues, and for subclassification the term melanotic progonoma should be maintained, too.

Female↗
PubMed2005

December 2004: one-year-old girl with aggressive skull tumor.

December 2004. Twelve-month old girl presented with recurrent subcutaneous lesion in the left parietal region, one year after excision of a "benign" tumor. An MRI demonstrated left temporo-parietal skull tumor infiltrating the soft tissue, surrounding craniotomy flap, and extending to the brain parenchyma. Biopsy revealed biphasic neoplasm displaying nests of poorly differentiated neuroblastic cells positive for synaptophysin and pigmented cuboidal epithelioid cell positive for keratins, epithelial membrane antigen and MHB-45. In addition, some neoplastic cells were immunoreactive for synaptophysin as well as HMB-45 and epithelial markers, suggestive of their origin from a common progenitor. Interestingly, cell with the neuroblastic immunophenotype displayed 80% nuclear MIB-1 reactivity indicating that the aggressiveness of the neoplasm was confined mostly to this pattern of differentiation. The overall histological features are consistent with a rare malignant variant of a melanotic neuroectodermal tumor of infancy.

Brain Neoplasms↗