Melanotic neuroectodermal tumor of infancy: a case report

BACKGROUND

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare clinically benign, pigmented, tumor of neural crest origin which commonly occurs in the maxilla. It is a rare tumor that may pose difficulty in differentiating from other malignant round cell tumors.

CASE PRESENTATION

A 5-month-old Ethiopian infant presented with a mass on his forehead. A wide excision of the lesion was done and subjected to histopathologic evaluation. The histologic and immunohistochemistry for synaptophysin studies confirmed that the infant was having MNTI. The patient was followed and there was no sign of recurrence at the 6th and 9th months of follow-up.

CONCLUSION

MNTI should be considered as a differential diagnosis for tumors occurring in the head region in infants and prolonged follow-up may be needed to check for possible recurrence of the tumor.

Melanotic Neuroectodermal Tumor of Infancy in the Epididymis: A Case Report

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm of neural crest origin that predominantly involves the craniofacial region, involvement of the epididymis being extremely rare, with about 30 cases reported. We report an unusual case of a 5-month-old male with MNTI in the epididymis. The patient underwent orchiectomy. Half a year later, there was no sign of recurrence. Whether preoperative examination or intraoperative frozen examination, the tumor may easily be misdiagnosed as malignancy. Melanotic neuroectodermal tumor of infancy should be included in differential diagnosis in infants presenting with fast-growing scrotal swelling.

Melanotic Neuroectodermal Tumor of Infancy: A Case Image

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare benign neoplasm that can be mistaken for malignancies due to its unfamiliarity among clinicians and aggressive clinical appearance. We herein contributed by reporting an additional case of MNTI characterized by an extensive extraoral protrusion in a 2-month-old infant. The lesion involved the anterior maxilla, cheek, and infraorbital region, resulting the displacement of the nose to the contralateral side, and measuring approximately 10 cm in size. Surgical resection of the lesion was performed. After a 6-month follow-up, the patient has shown no evidence of recurrence. The rapid growth and aggressive behavior of MNTI emphasize the importance of an early diagnosis and prompt intervention in order to achieve favorable outcomes.

Melanotic neuroectodermal tumor of infancy arising in the skull: a case report

Melanotic neuroectodermal tumor of infancy is a rare and usually benign neoplasm occurring in children of young age. This pigmented tumor typically presents in the head and neck region, but other locations may be involved. We report in this article a rare case of a 3-month-old girl presenting with a slowly growing mass localized in the anterior fontanelle. The patient's magnetic resonance imaging (MRI) showed a mass extending both extracranial and intracranial, and compressing the adjacent structures. The patient underwent subtotal resection of the mass and a histological study confirmed the diagnosis of melanotic neuroectodermal tumor of infancy. The patient presented later on with a recurrence. An early diagnosis and surgical management for these tumors remain the only guarantees to limit the progression and prevent their recurrence and metastasis.

Melanotic Neuroectodermal Tumour of Infancy

Melanotic neuroectodermal tumour of infancy (MNTI) is a locally aggressive neoplasm of neural crest origin. It is primarily a paediatric tumour, and 95% of the cases occur in children below 1 year. The tumour mainly affects the head and neck region. It shows a predilection for the craniofacial sites and the most common site affected is anterior maxilla. Microscopically, it is characterized by a biphasic population of neuroblastic cells and pigmented epithelial cells. Although generally considered as a benign tumour, it can invade the adjacent muscle and bone, causing destruction of the involved site. The rapidity in growth and the aggressive clinical behaviour of the tumour can be deceptive and hence lack of familiarity with the clinical characteristics of the tumour may often lead to an erroneous diagnosis of malignancy. The treatment of choice for MNTI is excision, and it is usually curative. Extensive surgery in a child may interfere with the normal growth and development of the facial structures and reconstruction can be very challenging in infants. Hence, early diagnosis is critical for the effective management. Clinical findings, histopathological features, and differential diagnosis of a classic case of melanotic neuroectodermal tumour of infancy are discussed.

Melanotic neuroectodermal tumor of infancy in the mandible: A case report

RATIONALE

Melanocytic neuroectodermal tumor of infancy (MNTI) is a rare benign pigmented neoplasm that arises from the neural crest and has an aggressive growth pattern. It is predominantly seen in infants under 1 year of age, and the most common site of involvement is the maxilla. The currently accepted treatment is removal by surgical resection. Herein, we report a case of MNTI that involved the anterior alveolar ridge of the mandible in a 6-month-old infant.

PATIENT CONCERNS

A case of a 6-month-old male child with a huge mass in the anterior alveolar ridge of the mandible.

DIAGNOSIS

The tumor was diagnosed using histopathological and immunohistochemical techniques on the biopsy specimen obtained following incisional biopsy. Based on the findings, a final diagnosis of MNTI was established.

INTERVENTIONS

Radical resection of the tumor was performed, after determining the extent of resection by referring to the mandibular 3D model created using the pre-operative CT data.

OUTCOMES

The postoperative course was uneventful, and no recurrence has been observed to date for more than 4 years after surgery.

LESSONS

This case emphasizes that early diagnosis and radical surgery are critical to the effective treatment, as MNTI exhibits rapid and destructive growth. It also requires careful and close follow-up because of high recurrence rates.

Melanotic Neuroectodermal Tumor of Infancy in the Epididymis: A Rare and Considerable Cause of Scrotal Mass

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm with a predilection for children that predominantly involves the craniofacial region. Here we report 2 cases of MNTI involving epididymis, placing emphasis on the sonographic features. Both appeared to be hypoechoic, regular shaped masses with abundant blood supplies. The unique sonographic features and age of predilection make it possible to diagnose MNTI within the scrotum by ultrasonography.

Melanotic neuroectodermal tumor of infancy in ovary: A rare case report

RATIONALE

Melanotic neuroectodermal tumor of infancy (MNTI) is an extremely rare benign pigmented neoplasm of neural crest origin with rapid expansile growth and a high recurrence rate. It is predominantly found in infants of <1 year of age, involvement of the head-and-neck region is the most common presentation though it is reported at other sites including mediastinum, shoulder, thigh, foot, epididymis, uterus and ovary. The patient reported here is the third case of MNTI presenting in an ovary, and the first reported in the infant ovary.

PATIENT CONCERNS

A 33-month-old girl was presented to our unit for a huge abdominal mass.

DIAGNOSIS

MNTI was eventually diagnosed by histological manifestations supplemented with immunohistochemical findings.

INTERVENTIONS

Exploratory laparotomy and complete resection were conducted successfully.

OUTCOMES

Postoperative course was uneventful and no recurrence was displayed in the 6-month follow-up.

LESSONS

This case emphasizes that pediatric surgeons and pathologists must always consider the possibility of MNTI while dealing with ovarian neoplasms in infants. Although considered to be a benign tumor, proper treatment and close clinicoradiological follow-up of this tumor are of great importance.

Melanotic neuroectodermal tumour of infancy of the jaws: an analysis of diagnostic features and treatment

The purpose of this study was to integrate the available published data on melanotic neuroectodermal tumour of infancy (MNTI) of the jaws into a comprehensive analysis of its clinical/radiological features, with emphasis on the predictive factors associated with recurrence. Eligibility criteria included publications with sufficient clinical/radiological/histological information to confirm the diagnosis. A total of 288 publications reporting 429 MNTI cases were included. MNTIs were slightly more prevalent in males and markedly more prevalent in the maxilla. Most of the lesions were asymptomatic, presenting cortical bone perforation and tooth displacement. Nine lesions were malignant, with metastasis in five cases. Enucleation was the predominant treatment (67.2%), followed by marginal (18.4%) and segmental resection (6.1%). Eighty-one of 356 lesions (22.8%) recurred. Recurrence rates were 61.5% for curettage, 25.3% for enucleation alone, 16.2% for enucleation+curettage, 20.0% for enucleation+peripheral osteotomy, 11.3% for marginal resection, 10.0% for segmental resection, 30.0% for chemotherapy, and 33.3% for radiotherapy. Enucleation and resection presented significantly lower recurrence rates in comparison to curettage. Curettage appears not to be the best form of treatment, due to its high recurrence rate. As resection (either marginal or segmental) is associated with higher morbidity, enucleation with or without complementary treatment (curettage or peripheral osteotomy) would appear to be the most indicated therapy.

Primary Melanotic Schwannoma with Typical Histology

We present a case of a 17-year male with a soft tissue density spreading from the neural foramina (T3) of the spinal cord and involving the right upper thoracic cavity. We managed the patient through surgical intervention and resected the complete tumor. Gross definition and microscopic findings of the resected tissue revealed the definitive diagnosis of melanotic schwannoma. The histological characteristics in this case were very specific and harbour an important diagnostic clue for this rare disease. Malignant melanoma was ruled out on the basis of histological findings. The patient recovered completely and was healthy on one-year follow-up.

Melanotic neuroectodermal tumor of infancy in the skull: a case report

Melanotic neuroectodermal tumor of infancy (MNTI) is a rarely occurring neoplasm of neural crest origin, appearing in children during the first year of life. MNTI is a benign tumor but is nonetheless locally aggressive; it usually originates from the maxilla and the mandible. Recognition of the diagnostic features of MNTI is important, so that it may be differentiated from benign lesions (dermoid or epidermoid cysts, vascular lesions) as well as from malignant lesions such as small round cell tumors. We present a case of a 2-month-old infant who developed right retroauricular swelling with extension through the calvarium and into the central nervous system. The tumor was totally resected. Aggressive benign or malignant lesions of the calvarium may entail dural infiltration and brain involvement, as in our case. Early diagnosis and surgery are thus mandatory for benign or malignant tumors of the calvarium.

Congenital salivary gland anlage tumor - in utero and postnatal imaging

We present a case of an infant with congenital salivary gland anlage tumor, with fetal and postnatal imaging. To the best of our knowledge, this is the first case describing the in utero imaging findings of salivary gland anlage tumor. A fetal MRI was performed secondary to the clinical finding of polyhydramnios, which identified a nasopharyngeal mass. Because findings were concerning for airway obstruction, the fetus was delivered by ex utero intrapartum treatment (EXIT) to airway procedure. A postnatal CT confirmed the findings of the fetal MRI. The lesion was resected when the baby was 4 days old and recovery was uneventful.

Melanotic neuroectodermal tumour of infancy: a case report

Melanotic neuroectodermal tumour of infancy is a rare benign pigmented tumour that typically appears in the first year of life. We report an atypical presentation of this tumour, associated with an erupted primary tooth in a 7-month-old boy. We discuss the clinical, radiographic and histologic features of this rare tumour, as well as its surgical management and the follow-up treatment plan.

March 2000: 5 month old boy with occipital bone mass

A 5 month old boy was found by his mother to have a bony mass behind the left ear which extended intracranially on MRI scan. At surgery it was entirely extradural in location. Microscopically, a biphasic appearance consisting of large pigmented cells arranged into tubules and small nonpigmented basophilic cells arranged into nests gave rise to a diagnosis of melanotic neuroectodermal tumour of infancy [MNETI]. One year after a wide local excision the patient is tumor-free and developing normally. The prognosis for MNETI in general is excellent with no requirement for additional radiotherapy or chemotherapy.

Feasibility of fine-needle aspiration in the diagnosis of two unusual childhood jaw tumor types: prognoma and cementifying fibroma

Cytology features of childhood jaw tumors are infrequently reported in the literature. Fine-needle aspiration cytology (FNAC) has been used with good results in the differential diagnosis of bone lesions, being an excellent tool for the diagnosis of metastases and in the frontline approach to primary lesions. We report 3 cases of young children aged 3 years (case 1), 5 months (case 2), and 15 years (case 3) with jaw tumors diagnosed by FNAC. In the first two cases the diagnosis was prognoma, and in the third case cementifying fibroma. Despite the clinical and imaging similarity of the 3 cases - large maxillary/mandibular tumors - their characteristic cytological features allowed a confident diagnosis, excluding other differential alternatives. In both case 1 and case 2 a dual cell population of neuroepithelial and melanocytic cells was identified, consistent with a melanotic neuroectodermal tumor. In case 3 the presence of a bland spindle cell population as well as of several nodular dense eosinophilic, osteoid-like (cement) matrices, indicated a cementifying fibroma. All cases were resected and confirmed by histological examination. A review of the literature, including differential diagnosis, addresses the utility of FNAC in childhood jaw tumors.

Unilateral facial swelling in an infant

The melanotic neuroectodermal tumour of infancy (MNTI) is an uncommon, usually benign neoplasm which is most commonly found in the maxilla. We describe the case of a 6-month-old boy who was referred with a swiftly increasing swelling of the left cheek. After imaging and biopsy, MNTI was confirmed, and surgical resection was performed. Literature demonstrates that most MNTIs occur in the head and neck area and most of those occur in the maxilla. Although most cases are benign, 6.5% are malignant with metastatic disease. Treatment and outcome are discussed in detail. The case highlights the importance of making the diagnosis MNTI early on in order to achieve an optimal outcome.

An unusual tumour causing neonatal respiratory distress

PROBLEM

We present the case of a term neonate referred shortly after birth because of breathing and feeding difficulties.

METHODOLOGY

Fiber-endoscopic examination of the nasal cavity showed a pendulating mass in the nasopharynx.

RESULTS

A complete surgical resection was performed and the baby recovered completely. Microscopic examination of the mass showed an overlying non-keratinized squamous cell lining with an atypical cell population in some fragments. Histological features were compatible with a high-grade epithelial tumour like a midline carcinoma, but a final diagnosis of a salivary gland anlage tumour was established.

CONCLUSION

Flexible fiber endoscopy is the method of choice for examining the nasal passages and oropharynx in neonates with respiratory distress. Congenital salivary gland anlage tumour is a rare cause of neonatal nasal obstruction; it is benign and complete excision results in a cure. Histologically, it may mimic a malignant tumour owing to the high mitotic index.

Melanotic neuroectodermal tumour of infancy: report of two cases and review of the literature

Melanotic neuroectodermal tumour of infancy (MNTI) is an uncommon tumour affecting predominantly the craniofacial bones of the newborn infants. The neural crest origin of the tumour has been confirmed. MNTI is generally accepted as a benign tumour despite of its rapid and locally infiltrative growth. Recurrence rate varies between 10% and 60%, and malignant behaviour has been reported in 6.5% of MNTIs. Systematic review of the literature revealed 445 MNTIs published between 1918 and 2010. We present additional two cases of MNTI from our Department, typical in all terms, which equals a total number of 447 reported cases. One of our cases revealed histological features consistent with malignant behaviour, but at present, 18 months after the surgical excision, there is no evidence of recurrence. Biological behaviour of MNTI cannot be predicted by gross or histologic characteristics, thus early diagnosis and careful follow-up after the complete surgical excision is required.

Melanotic neuroectodermal tumour of infancy

Melanotic neuroectodermal tumour in infancy is rare, mainly benign with little tendency to recur after excision or effective curettage. This pigmented neoplasm of neural crest origin occurring in infants before 1 year of age. The most common site of occurrence is the anterior maxillary alveolar ridge (70%), following by the skull, brain and mandible. The genital organ is the most frequent extra cranial site. We report a 6 months old male baby with a similar tumour arising from right half of cheek involving the maxilla. We diagnosed the case after histological report. We remove the tumour through a sub-labial incision. The mass was blackish in colour, and was mobilized from all side including from the maxillary sinuses. The author thought that this should be reported for improving the clinical awareness and treatment of pigmented soft tissue mass in children. Almost one year follow up of the patients showed no recurrence.

Melanotic neuroectodermal tumour of infancy

Melanotic neuroectodermal tumour of infancy (MNTI) is a rare benign tumour of neural crest origin that was first described by Krompecher in 1918.1 It is predominantly found in infancy, with about 92% of cases below the age of 12 months and 82% below the age of 6 months. The predominant site of origin is in the premaxilla though it is reported at other sites also including the skull, the mandible, the epididymis and the brain.2 The lesions often have areas of bluish discolouration on the surface and are characterised by displacement of the involved tooth bud and local aggressiveness. The present report deals with two cases of MNTI, a 5-month-old baby girl and a 6-month-old baby boy who reported to the Department of Oral and Maxillofacial Pathology, Dr R Ahmed Dental College and Hospital, Kolkata, India. The clinical, radiological, histological and immunohistochemical findings, confirmed the diagnosis of MNTI. Flow cytometry was performed to analyse aneuploidy. The tumours were treated surgically with no history of recurrence to date.

Salivary gland anlage tumor in a neonate presenting with respiratory distress: radiographic and pathologic correlation

We present a case of congenital salivary gland anlage tumor (SGAT) of the nasal septum in a 2-week-old infant who had difficulty breathing through her nose since birth. CT and MR imaging demonstrated a circumscribed mass within the nasal cavity that did not communicate with the intracranial compartment. Differential diagnosis and clinical significance of recognizing this rare lesion are reviewed.

[Diagnosis and management of oral melanotic neuroectodermal tumor of infancy]

OBJECTIVE

To investigate the clinicopathological features of oral melanotic neuroectodermal tumor of infancy (MNTI).

METHODS

We retrospectively reviewed the clinical and pathological data of 13 cases of oral MNTI treated in Peking University School and Hospital of Stomatology from 1980 to 2007.

RESULTS

The age of patients ranged from 2 to 7 months old. Nine lesions occurred in the maxilla, 3 in the mandible and 1 in the cheek. The most common symptom of the disease was swelling. Five tumors were found purple-reddish or blue-blackish. The neoplasm grew rapidly. Only 1 case was diagnosed as MNTI and 3 cases were diagnosed as malignant tumor before biopsy. Two of 9 cases with follow-up information recurred in one month after surgery and 1 case dead of the tumor. One case with remnants of tumor did not recur after 19 years postoperatively.

CONCLUSION

Oral MNTIs appear to occur in certain locations and people of certain age. Special attention should be paid to the color of the tumor during intra-oral examination. This tumor grew rapidly and invasively and the patients require close follow-up within the first 6 months postoperatively. The pathologic differential diagnosis of MNTI should include other pediatric "small round cell" neoplasms. Conservative excision is the preferred treatment choice.

Orbital melanotic neuroectodermal tumor of infancy successfully treated with chemotherapy and subtotal excision

Melanotic neuroectodermal tumor of infancy is a rare condition that typically presents within the first 6 months of life. It rarely metastasizes but is locally aggressive. Melanotic neuroectodermal tumor of infancy has been reported under several other names including retinal anlage tumor and melanotic progonoma. Most commonly, melanotic neuroectodermal tumor of infancy originates in the maxilla. Tumors in previously reported orbital cases have arisen from adjacent structures or from orbital bone. Recommended treatment of melanotic neuroectodermal tumor of infancy has consisted of complete excision with wide tissue margins, although success has been reported after incomplete resection. For those patients in whom surgical resection is not possible, various chemotherapy approaches have been reported with mixed results ranging from failure to sustained tumor regression. We report a case of orbital melanotic neuroectodermal tumor of infancy adherent to sclera and successfully treated with chemotherapy and subtotal excision.

Melanotic neuroectodermal tumor of infancy: report of a case with myogenic differentiation

An 8-month-old boy presented with a 6-week history of a skull mass of the anterior fontanelle. The mass was excised, and the histopathologic features were diagnostic for melanotic neuroectodermal tumor of infancy. The tumor showed focal myogenin positivity, which has not been previously reported in this tumor. The patient has no evidence of recurrent tumor 10 months after the excision. No adjuvant therapy was given. In addition, we stained a case of melanotic neuroectodermal tumor of infancy obtained from Columbus Children's Hospital; focal myogenin positivity was present.

Melanotic neuroectodermal tumor of infancy of the femur

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare neoplasm that often occurs during the first year of life. More than 90% of MNTIs occur in the head and neck region, with most on the anterior part of the maxillary ridge. MNTI has also been reported in the mediastinum, thigh, foot, shoulder, and gonads. Here the authors report a rare case of MNTI of the femur in a 3-month-old child.

Review of Pineal Anlage Tumor With Divergent Histology

Pineal anlage tumor is an extremely rare tumor that is not listed in the 2000 World Health Organization Classification of nervous system tumors. It has been defined as a primary pineal tumor with both neuroepithelial and ectomesenchymal differentiation and without endodermal differentiation. We review the literature on this tumor, including the clinical presentation, gross pathology, histopathology, immunohistochemistry, differential diagnosis, and prognosis.

Diagnostic cytologic features of an epididymal melanotic neuroectodermal tumor of infancy present in scrotal fluid: a case report

BACKGROUND

The cytologic features of melanotic neuroectodermal tumor of infancy (MNTI) have been described in rare cases only, and these reports have been based solely on direct smears obtained from aspirated tumor material or from touch preparations of resected tumors.

CASE

We report, to our knowledge, the first documented case of an epididymal MNTI diagnosed from aspirated hydrocele fluid processed using the ThinPrep system (Cytyc Corp., Boxborough, Massachusetts, U.S.A.).

CONCLUSION

Based on a 15 year retrospective review of scrotal fluids submitted for cytologic evaluation to our laboratory, MNTI represented the sole neoplasm that was represented in the fluid and could be specifically diagnosed. Compared to the direct smear evaluation in our case and other published reports, the ThinPrep method enables the recognition of both neuroblast-like cells and larger melanin-containing epithelial cells in scrotal fluid, thereby aiding in the specific diagnosis of MNTI and minimizing the risk of misdiagnosing this tumor as a more aggressive neoplasm.

Melanotic neuroectodermal tumor of infancy: case report

INTRODUCTION: Melanotic neuroectodermal tumor of infancy (MNTI) is a rare tumor, locally aggressive, usually originated from maxilla and mandible and rarely from the skull. A case of a 4 month-old child presenting a bulging lesion in the midline of the occipitoparietal region with progressive growth is reported. CASE REPORT: The neurologic examination had normal developmental milestones. Computerized tomography scan and magnetic resonance Image showed a highly enhancing tumor, dislocating anteriorly and inferiorly the superior sinuses. In order to prevent excessive bleeding, surgical resection was performed in three stages, with complete removal. CONCLUSION: Based on the absence of tumor recurrence, we believe in a favorable neurological prognosis and in a possible of cure, although the patient was not submitted to any adjuvant treatment.

Recurrent melanotic neuroectodermal tumour of infancy of the epididymis and testis: a case report

Melanotic neuroectodermal tumor of infancy or melanotic progonoma is an uncommon tumor, presenting in infants. The epididymis and testis are rare sites of occurrence. This tumor can be confused with round cell tumor (RCT). Since the treatment modality and prognosis of melanotic progonoma and RCT are very different, it is imperative to make a correct diagnosis.

Melanotic neuroectodermal tumour in an infant

Most jaw swellings in infancy are benign odontogenic cysts or tumours. The encounter with an unusual melanotic neuroectodermal tumour of the jaw in a young infant is described in this report. There has been no recurrence, after complete surgical excision, in a follow-up period of six months.

[Melanotic neuroectodermal tumor of infancy]

BACKGROUND

The melanotic neuroectodermal tumor of infancy is a rare and so far as being classified neoplasm with a high rate of recurrence for one year after diagnosis. Since Krompecher described 1918 the tumor at first, only about 200 cases are reported until today, mostly with manifestation in the maxillary region.

CASE-REPORTS

The authors present two infants at the age of six and eight weeks with first clinical manifestation of the tumor in the maxillary region. Although there were no other common signs, the tumor destroyed wide areas of the mid-face. In spite of a treatment with radical surgery, recurrences occur rapidly in the first living year.

CONCLUSIONS

Our clinical and histological findings show characteristics of local malignant growth. For these facts the radical resections of the primary tumor and its recurrences are individually the therapeutical consequences. A follow up of seven years of one infant shows a hypoplasm of the mid-face as a result of the inhibition of further growth by the loss of germs after maxillary hemisection.

The operating microscope in the management of melanotic neuroectodermal tumor of infancy

Melanotic neuroectodermal tumor of infancy is a rare condition that is most commonly found within the head and neck regions. We present a 4-month-old boy with a melanotic neuroectodermal tumor of infancy of his maxilla. Because of the fairly high recurrence rate, the operating microscope was used after surgical excision to remove unseen remnants of the pigmented lesion. The patient has been followed for 4 years without signs of recurrence.

Benign melanocytic tumor in infancy: discussion on a rare case and review of the literature

Meningeal melanocytoma is an infrequent neoplasm of the central nervous system (CNS), especially in childhood and infancy. It was first described as an entity different from pigmented meningiomas and schwannomas in 1972, and few cases have been published so far. In this article, a 5-month-old male patient with meningeal melanocytoma is presented. This midline lesion was localized in the posterior fossa and manifested by hydrocephalus. The entire dural origin and extradural growing pattern in addition to the destruction of the adjacent occipital bone were the unexpected presentations since these tumors usually tend to locate on leptomeninges and to extend into the adjacent neural compartment rather than the outside. On the other hand, this case is the only one which had identical lesions in both surrenal glands and the left renal capsule, the structures containing neural-crest-derived cells outside the CNS. The prognostic criteria, differential diagnosis and its embryological aspects are discussed with an extensive review of the related existing literature.

Melanotic neuroectodermal tumor of infancy: report of two cases and review of literature

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, distinctive neoplasm containing melanin; it primarily affects the maxilla of the infants during the first year of life. Approximately 150 instances of this tumor are reported in the medical literature. Genesis of the tumor is obscure and the diagnosis is challenging for the pathologist. Two cases operated by the first author are presented, and the diagnostic features and treatment alternatives of MNTI discussed.

Cytologic diagnosis of a melanotic neuroectodermal tumor of infancy occurring in the cranial bones

Melanotic neutroectodermal tumor of infancy (MNTI) is a rare, usually benign tumor commonly occurring in the maxilla. MNTIs at unusual sites like the cranium clinically mimic malignant small round cell tumors. Consequently, a correct preoperative cytologic diagnosis of MNTI at these sites helps in the surgical management of the patient. We report on a cytologically diagnosed case of MNTI in the frontotemporal region of the skull in an infant. Aspirates from the lesion were cellular, with a bimodal population mainly of small neuroblast-like cells admixed with a few large epithelioid cells with melanin granules. In the present case, following the cytologic diagnosis a wide local excision was carried out, and the histologic examination confirmed the cytologic diagnosis. Diagn. Cytopathol. 1999;21:280-283.

Melanotic neuroectodermal tumour of infancy at the anterior fontanelle

We describe a 4-month-old girl presenting with a melanotic neuroectodermal tumour of infancy at the anterior fontanelle. According to the neuroimaging findings, this tumour was found to lie epidurally, adherent to the dura mater, with thickening of the adjacent frontal bone. The tumour was dense on CT, while MRI showed a major part of the tumour to be isointense with cerebral cortex on both T1- and T2-weighted images. The neuroimaging and clinical features are briefly discussed.

Malignant melanotic neuroectodermal tumour of infancy affecting the occipital squama

An unusual case of a melanotic neuroectodermal tumour of the occipital squama, which underwent malignant transformation in a nine-month-old infant is reported and pertinent literature reviewed.

Pigmented neuroectodermal tumor of infancy in the epididymis. A case report

BACKGROUND

Pigmented neuroectodermal tumor of infancy (PNTI) is a rare pigmentary tumor. Cytologic study of this tumor had not been performed before. In the present study, cytology of such a tumor was done in addition to histology, electron microscopy and immunohistochemistry.

CASE

A 5-month-old infant had a scrotal tumor. After tumorectomy, touch smear for cytology revealed small and large tumor cells. The small cells showed a high nuclear/cytoplasmic ratio, and the large cells contained pigment in their cytoplasm. Histologically, the small cells and large, pigmented cells showed a typical alveolar and tubular pattern, respectively. The small cells neuroblastlike and the large cells showed melanocytelike features ultrastructurally and immunohistochemically.

CONCLUSION

Cytology has not been applied to the diagnoses of PNTI. In our opinion, fine needle aspiration cytology could be helpful in the preoperative diagnosis of this tumor.

Melanotic neuroectodermal tumor of infancy

A 6-month-old female presented with a swelling of the left superior maxillary bone. A radiograph revealed a radiolucent lesion in the left anterior maxilla, and CT, showed a solid mass. At surgery, the lesion was a cystic dental tumor of ectopic location which was treated by excision. The pathological diagnosis was melanotic neurorectodermal tumor. This is an uncommon benign tumor of the neural crest origin that occurs mainly in the maxilla (70% of cases) but can occur in other areas such as the skull and the mandible. CT reveals a hyperdense mass and MR shows a hypointense mass on T1-weighted images and an iso-intense mass on T2-weighted images. The evolution is usually benign after surgical removal.

Three-dimensional reconstruction of melanotic neuroectodermal tumor of infancy involving the occipital bone and dura

A rare case of melanotic neuroectodermal tumor of infancy involving the right occipital bone in an 11-month-old infant is described. The bone tumor and its dural extension were surgically removed. Three-dimensional reconstruction of the tumor and brain from neuroimaging data added worthwhile information for preoperative planning. Microscopic examination revealed melanotic and neuroblastic tissue in a fibrillary matrix involving the expanded bone and superficial dura. A focal osteoblastic cranial mass in an infant should alert the clinician to consider this tumor.

Melanotic neuroectodermal tumor of infancy in the epididymis. Case report and literature review

We report a case of melanotic neuroectodermal tumor that originated in the right epididymis of a 4-month-old Japanese male and review reports of similar cases. Since we could not exclude malignant disease preoperatively, we performed a radical orchiectomy. Histopathological and immunohistochemical studies revealed features characteristic of a melanotic neuroectodermal tumor. Imaging studies showed no distant metastases.

Melanotic neuroectodermal tumor of infancy: a molecular approach to diagnosis. Case report

A case of melanotic neuroectodermal tumor of infancy arising from the transverse sinus is presented. The tumor was located on the outer surface of the dura and extended extracranially through the occipitomastoid suture. Two cell populations were observed: pigmented melanocyte-like cells and small neuroblast-like cells. Ultrastructural analysis revealed epithelial tumor cells and melanosomes at various stages. Expression of melanotransferrin messenger RNA transcripts within the tumor tissue was observed using a reverse transcriptase-polymerase chain reaction method in addition to immunohistological studies. The positive expression of melanotransferrin confirmed that this melanotic neuroectodermal tumor was derived from neural crest cells.

[Melanotic neuroectodermal tumor in an infant]

BACKGROUND

Melanotic neuroectodermal tumor is a mostly benign tumor, rare in childhood, essentially located in the head and neck region.

CASE REPORT

A two-month-old girl was seen for a rapidly increasing odontogenic tumor which appeared cystic at the CT scan. After enucleation, this premaxillar tumor recurred one month later with an osteogenic aspect at the CT scan. Urine catecholamine excretion was normal; Methyl Iodo Benzyl Guanidin scintigraphy failed to show any fixation and electron microscopy examination of the biopsy showed several varieties of melanocytes. A partial maxillectomy was performed by oral approach. The patient is well 4 1/2 years later.

CONCLUSION

This observation confirms the recurrence potential of this tumor and the cosmetic interest of the oral surgical approach.

MR of parenchymal neurocutaneous melanosis

Two cases of neurocutaneous melanosis are presented. MR showed hyperintense areas in the brain on short-repetition-time/short-echo-time sequences, compatible with intraparenchymal melanin deposits. No leptomeningeal abnormality was seen.

Melanotic neuroectodermal tumor of infancy

We present a case of malignant melanotic neuroectodermal tumor of infancy arising in the skull and secondarily invading brain. The central tumor was hyperintense to brain on T1-weighted images and hypointense to brain on T2-weighted images. This appearance corresponded to the surgical and histologic findings of melanin-containing tumor.

Neurocutaneous melanosis presenting as an intradural mass of the cervical canal: magnetic resonance features and the presence of melanin as a clue to diagnosis: case report

We present a case of neurocutaneous melanosis in a 1-year-old child who presented with progressive quadriparesis created by an infiltrating extra-axial neoplastic melanin-producing tumor at the foramen magnum. This extensive intra-arachnoid mass filled the basal cisterns of the brain and surrounded the upper cervical cord. An imaging clue to the diagnosis was apparent as T1-weighted shortening on magnetic resonance in the pia and/or cortex of the cerebellar folia, suggesting the presence of melanin.