Melanotic Neuroectodermal Tumor Of Infancy Research Articles

Malignant melanotic neuroectodermal tumor of infancy. A clinical, pathologic, ultrastructural and tissue culture study

Malignant melanotic neuroectodermal tumor of infancy. A clinical, pathologic, ultrastructural and tissue culture study

Melanotic neuroectodermal tumor of infancy (Pigmented melanoameloblastoma)

The paper describes a large pigmented maxillary tumor in a 46-day-old infant. The histological examination showed the tumor to be a melanotic neuroectodermal tumor of infancy (MNTI). No raised urinary levels of vanilmandelic acid could be shown. The tumor was surgically removed and during a 5½-year follow-up period there was no clinical evidence of recurrence. The origin, behavior and treatment of these rare tumors are discussed.

Malignant melanotic neuroectodermal tumor of infancy.A clinical, pathologic, ultrastructural and tissue culture study

The melanotic neuroectodermal tumor of infancy is an uncommon neoplasm typically of early childhood which has a predilection for the head and neck region, particularly the maxilla. Except for one previous example in the literature, this tumor has consistently behaved in a benign fashion. This study documents the clinical course and pathologic findings of a tumor which began in the maxilla of a 4-month-old boy, followed by a local recurrence, metastasis to a cervical lymph node and finally, widespread dissemination and death at 18 months, 24 months and 38 months, respectively. The tumor was initially composed of nests consisting of melanin-containing cells and small dark cells. An elevated vanillylmandelic acid level was recorded during the course of the disease. At autopsy, the tumor in lymph nodes, liver, bone and soft tissues had a monotonous pattern of small dark cells similar to a conventional neuroblastoma. Previous ultrastructural studies indicate that the melanotic neuroectodermal tumor of infancy is composed of melanocytes and neuroblast-like cells. Our case provided the unique opportunity to examine in sequence the ultrastructural and in vitro characteristics of a recurring and eventually metastasizing melanotic neuroectodermal tumor. Although the neuroblast-like cells were initially difficult to identify by electron microscopy, a melanin-producing cell line and a separate nonpigmented cell line were successfully isolated from various tumor explants. Various stages of melanosome development were identified in the pigmented cells from the local recurrences and in vitro. Dibutyryl cAMP accentuated the formation of pigment and dendritic development in the melanocytes and dendrites only in the small nonpigmented cells. Electron dense granules were observed in the cultured smaller cells and also in the lymph node and soft tissue metastases. Tyrosine hydroxylase activity was demonstrated in the neuroblast-like cells. In the final biopsy and autopsy material, only the neuroblast-like cells remained and the tumor resembled a conventional neuroblastoma.

Melanotic neuroectodermal tumor of infancy

The lack of knowledge regarding the histogenesis of the melanotic neuroectodermal tumor of infancy may account for the numerous names given to this neoplasm. The most appropriate nomenclature is melanotic neuroectodermal tumor of infancy as this term is both clinically descriptive and reflects its most likely histogenesis. The histological diagnosis of this neoplasm and its known benign biological behavior should be appreciated so that radical surgery or radiotherapy is not undertaken. Our case report includes an electron microscopic analysis which is in keeping with other reported cases. We have not confirmed high urinary VMA levels prior to resection of the lesion.

Melanotic neuro-ectodermal tumour of infancy (melanotic progonoma) in two calves

Large unilateral tumours involving the mandible in two calves were composed of melanin-containing cells and small lymphocyte-like cells in a cellular fibrous stroma. These neoplasms resembled the melanotic neuro-ectodermal tumour of infancy.

A Melanotic Neuroectodermal Tumor of Infancy Arising from the Anterior Fontanel

A case of local recurrence of melanotic neuroectodermal tumor of infancy (MNT), arising from the anterior fontanel in a 6-month-old female, is presented. The follow-up of 48 months after surgery confirms the benign nature of this tumor despite its local recurrence. Clinical and histopathologic chracteristics of this rare tumor are discussed. A review of 12 cases of MNT involving the skull is given. It is emphasized that this entity should be kept in mind in the differential diagnosis of a mass in the craniofacial structures in infancy.

Ultrastructural Evidence for Neural Crest Origin of the Melanotic Neuroectodermal Tumor of Infancy

A case of malanotic neuroectodermal tumor of infancy, which occurred in the anterior maxilla of a 3-month-old girl, was studied by electron microscopy. Polymorphic cellular elements were revealed to be present: large melanin-producing cells with some of the characteristics of a neuroepithelium, small non-pigmented cells resembling immature neuroblasts, and many intermediate forms resembling differentiating neuroblasts. All cell types clearly demonstrated ultrastructural features of neurogenic cells, e.g. neurite-like cytoplasmic processes, fine filaments and microtubules indistinguishable from those seen in normal neurites, synaptic-like structures, and neurosecretory-like vesicles. Based on these fine structures, the lesion was presumed to represent a hamartoma of primitive neuroectodermal cells with a tendency toward the differentiation into melanin-producing cells. The neural crest origin of this tumor was convincingly supported by ultrastructural analysis.

Melanotic neuroectodermal tumor of infancy: review of the literature and report of case

A characteristic case of melanotic neuroectodermal tumor of infancy is reported and the literature regarding this lesion is reviewed. The case reported shows the salient features of previously described melanotic neuroectodermal tumors of infancy; it occurs in infants of less than 1 year of age; it most commonly arises from bone (jaws and skull), has distinctive gross and histologic features, is benign, and is cured by total local excision. Since the teeth in the mandible and maxilla are undergoing development about the time that this tumor occurs, it is not surprising to find tooth buds in close proximity to the expanding neoplastic mass. When odontogenic rests are found in association with the lesion, it must be assumed that it is a collision of the two structures and not that the odontogenic epithelium is the origin for the lesion as previously thought. This is especially true since odontogenic epithelium is not found in the tumor when it occurs outside the jaws. This is the type of lesion that will most probably first be noticed by a dentist and should be managed by the oral surgeon. It is important to note that proper advice regarding future dental problems should be given to the parents of the infant. Such possibilities as crowding or absence of the deciduous or permanent teeth, malocclusion, and possible malformation of the remaining maxillary ridge should be explained. Close dental follow-up is mandatory since recurrence is possible.

Melanotic Neuroectodermal Tumour of Infancy: Report of a Case

A case of melanotic neuroectodermal tumour occurring in a seven-month-old male infant is reported. The aetiopathogenesis, clinical features, treatment and prognosis of the condition are discussed. Tumours of the jaw in infancy are extremely rare, and pigmented tumours still rarer. One such case of pigmented tumour of the maxilla is the subject of this report.

Melanotic neuroectodermal tumor of infancy: Report of a case

The melanotic neuroectodermal tumor of infancy is locally invasive but benign and does not metastasize. The case presented here involved a 4-month-old girl.

Melanotic Medulloblastoma of the Cerebellum

A case of a melanotic cerebellar tumor in a three year old child is described. The tumor has a close histological resemblance to the melanotic neuroectodermal tumor of infancy occurring extracranially. Despite this, the histological appearance, the site of involvement, the age incidence, and the malignant behavior of the tumor are similar to that of the usual medulloblastoma. Furthermore, the predominating cellular element of the tumor is indistinguishable from that of the medulloblastoma. The melanotic cerebellar tumor is, therefore, considered to be a variant of medulloblastoma and is designated as melanotic medulloblastoma.

An outline of power ultrasonics : Perkins, J. Oem Des Vol 1 No 5 (February 1972) pp 42–47

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, rapidly growing pigmented neoplasm of neural crest origin generally arising in infants during the first year of life.We report a 15-month old male who presented with a 2-month history of a rapidly growing mass in the anterior. A biopsy showed melanotic neuroectodermal tumor, and complete resection with negative margins was subsequently achieved. The patient is in remission at 11 months from surgery.Due to its rapid growth potential and locally destructive behaviour, early diagnosis is extremely important to limit local expansion. The treatment of choice for melanotic neuroectodermal tumor of infancy (MNTI) is surgical excision.

Melanotic neuroectodermal tumor of infancy—A neoplasm of neural crest origin: E. D. Borello and R. J. Gorlin. Cancer 19:196, 1966

Melanotic neuroectodermal tumor of infancy—A neoplasm of neural crest origin: E. D. Borello and R. J. Gorlin. Cancer 19:196, 1966